From: Intrinsic User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.5) Gecko/20031024 Debian/1.5-2 X-Accept-Language: en MIME-Version: 1.0 Newsgroups: alt.folklore.computers Subject: Altair 8800 Replica Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Original-NNTP-Posting-Host: 203.220.42.170 Message-ID: <4092463b$1@news.comindico.com.au> X-Original-Trace: 30 Apr 2004 22:27:39 +1100, 203.220.42.170 Lines: 12 Date: Fri, 30 Apr 2004 12:27:40 GMT NNTP-Posting-Host: 203.194.27.1 X-Complaints-To: abuse@comindico.com.au X-Trace: news.optus.net.au 1083328060 203.194.27.1 (Fri, 30 Apr 2004 22:27:40 EST) NNTP-Posting-Date: Fri, 30 Apr 2004 22:27:40 EST Organization: Comindico Australia - reports relating to abuse should be sent to abuse@comindico.com.au Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!switch.ch!news.imp.ch!news.imp.ch!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!news1.optus.net.au!optus!news.optus.net.au!53ab2750!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:172947 Hi, I am currently considering building a replica of the Altair 8800, however as I want it to be as faithful to the original as possible, I need to find a working Intel 8080 CPU somewhere (If not and 8080 and 8080A would be ok but I'd prefer the original 8080 as that's what was used in the earliest models), (I know the Z-80 is virtually identical if not better however like I say I want it as faithful as possible), I am willing to ship from the US/Europe but Oceania would be better as I'm in Australia. Thanx Intrinsic ###### NNTP-Posting-Date: Fri, 30 Apr 2004 09:41:01 -0500 From: "Jack Peacock" Newsgroups: alt.folklore.computers References: <4092463b$1@news.comindico.com.au> Subject: Re: Altair 8800 Replica Date: Fri, 30 Apr 2004 07:41:00 -0700 X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 6.00.2800.1409 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1409 Message-ID: Lines: 23 NNTP-Posting-Host: 66.18.133.20 X-Trace: sv3-6Db9TuZLl4oNTjgorAcK8HvDtIS5fUSykOUBzVrOCd9Hu9eLagkAjJdzBxemk+oH7gQmQMsSKlSWUFl!7Vhlcoqdm8FNp3udd8KGgDhq4PS9BBeS65tncLmhMPRqt8BzOKfuvoXXReLupgE0jqdI2JxSj2UO!p70= X-Complaints-To: abuse@mpowercom.net X-DMCA-Complaints-To: abuse@mpowercom.net X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.1 Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!irazu.switch.ch!switch.ch!newsfeed00.sul.t-online.de!t-online.de!newsfeed.freenet.de!news2.euro.net!border1.nntp.ash.giganews.com!nntp.giganews.com!local1.nntp.ash.giganews.com!nntp.mpowercom.net!news.mpowercom.net.POSTED!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:172974 "Intrinsic" wrote in message news:4092463b$1@news.comindico.com.au... > Hi, > I am currently considering building a replica of the Altair 8800, > however as I want it to be as faithful to the original as possible > While it may be worthwhile to build a replica for some kind of historical perspective the fact remains the Altair design was not the high point of technical design or layout. There was a reason the IMSAI used the plug in front panel instead of 100 individual bus jumpers. That's why no one ever copied the Altair version of the S-100. And what about the power supply? Will you stay with the original underpowered unit or go with the 8800B size power supply? One of the first add-on kits for the Altair was a replacement power supply by a company called Parasitic Engineering (if ever a company had a more descriptive name). You have a source for the Optimus case? That was one of the main selling points used by MITS over the IMSAI. Jack Peacock ###### From: et472@FreeNet.Carleton.CA (Michael Black) Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica Date: 30 Apr 2004 16:02:00 GMT Organization: The National Capital FreeNet Lines: 29 Message-ID: References: <4092463b$1@news.comindico.com.au> Reply-To: et472@FreeNet.Carleton.CA (Michael Black) NNTP-Posting-Host: smeagol.ncf.ca X-Trace: freenet9.carleton.ca 1083340920 20918 134.117.136.48 (30 Apr 2004 16:02:00 GMT) X-Complaints-To: complaints@ncf.ca NNTP-Posting-Date: 30 Apr 2004 16:02:00 GMT X-Given-Sender: et472@smeagol.ncf.ca (Michael Black) Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!switch.ch!news.ip-plus.net!newsfeed.ip-plus.net!news.tesion.net!news.belwue.de!news.tu-darmstadt.de!newsfeed.freenet.de!216.196.98.140.MISMATCH!border1.nntp.ash.giganews.com!nntp.giganews.com!news.glorb.com!news-spur1.glorb.com!news.kjsl.com!xcski.com!freenet-news!FreeNet.Carleton.CA!et472 Xref: redlance.franklin.ch alt.folklore.computers:172989 Intrinsic (mreed13@hotmail.com) writes: > Hi, > I am currently considering building a replica of the Altair 8800, > however as I want it to be as faithful to the original as possible, I > need to find a working Intel 8080 CPU somewhere (If not and 8080 and > 8080A would be ok but I'd prefer the original 8080 as that's what was > used in the earliest models), (I know the Z-80 is virtually identical if > not better however like I say I want it as faithful as possible), I am > willing to ship from the US/Europe but Oceania would be better as I'm in > Australia. > Thanx > Intrinsic > The Z-80 would not be "virtually identical". A different brand of 8080, or the "A" or even a much later date code on the device would still be an 8080. You could start with whatever's cheap and available, and if you really wanted "authentic" search, and maybe pay, for an 8080 of early vintage, and put it into the circuit. But if you use a Z-80 it's not an Altair 8800. The pinout is not the same, the external circuitry (and maybe timing) is different. The only way one could use a Z-80 in there is by changing the circuitry, or doing as they would have done back then, a small board that plugs into the 8080 socket. Michael ###### From: glen herrmannsfeldt User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.4) Gecko/20030624 Netscape/7.1 (ax) X-Accept-Language: en-us, en MIME-Version: 1.0 Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica References: <4092463b$1@news.comindico.com.au> In-Reply-To: <4092463b$1@news.comindico.com.au> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Lines: 16 Message-ID: <33Akc.4758$0H1.486611@attbi_s54> NNTP-Posting-Host: 24.18.177.15 X-Complaints-To: abuse@comcast.net X-Trace: attbi_s54 1083362623 24.18.177.15 (Fri, 30 Apr 2004 22:03:43 GMT) NNTP-Posting-Date: Fri, 30 Apr 2004 22:03:43 GMT Organization: Comcast Online Date: Fri, 30 Apr 2004 22:03:43 GMT Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!irazu.switch.ch!switch.ch!news.maxwell.syr.edu!wn51feed!worldnet.att.net!attbi_s54.POSTED!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173024 Intrinsic wrote: > Hi, > I am currently considering building a replica of the Altair 8800, > however as I want it to be as faithful to the original as possible, I > need to find a working Intel 8080 CPU somewhere (If not and 8080 and > 8080A would be ok but I'd prefer the original 8080 as that's what was > used in the earliest models), I think I still have the PC board plans. I was in high school when it came out, so I couldn't really afford to buy one, but I did mail in for the plans. It was a Popular Electronics project, so they would always supply a mail address for the plans. -- glen ###### Message-ID: <409394F6.4C67558B@optushome.com.au> Date: Sat, 01 May 2004 22:15:50 +1000 From: Rob Storey Organization: @Home X-Mailer: Mozilla 4.6 [en-gb]C-AtHomeI0407 (Win98; I) X-Accept-Language: en-GB,en,en-* MIME-Version: 1.0 Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica References: <4092463b$1@news.comindico.com.au> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Lines: 26 NNTP-Posting-Host: 211.28.100.186 X-Trace: 1083413911 436 211.28.100.186 Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!switch.ch!news.imp.ch!news.imp.ch!news.moat.net!border1.nntp.sjc.giganews.com!border2.nntp.sjc.giganews.com!nntp.giganews.com!news1.optus.net.au!optus!newsfeeder.syd.optusnet.com.au!news.optusnet.com.au!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173079 Intrinsic wrote: > > Hi, > I am currently considering building a replica of the Altair 8800, > however as I want it to be as faithful to the original as possible, I > need to find a working Intel 8080 CPU somewhere (If not and 8080 and > 8080A would be ok but I'd prefer the original 8080 as that's what was > used in the earliest models), (I know the Z-80 is virtually identical if > not better however like I say I want it as faithful as possible), I am > willing to ship from the US/Europe but Oceania would be better as I'm in > Australia. > Thanx > Intrinsic I'm in Melbourne, and I'm almost certain that there's at least an 808A lurking inside the piles of junk that I seem to accumulate. I'll have a dig sometime over the next few days and let you know. What about building an EDUC-8? I still have the book that compiled all the EA articles together. Cheers, Rob Storey ###### From: Intrinsic User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.5) Gecko/20031024 Debian/1.5-2 X-Accept-Language: en MIME-Version: 1.0 Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica References: <4092463b$1@news.comindico.com.au> <409394F6.4C67558B@optushome.com.au> In-Reply-To: <409394F6.4C67558B@optushome.com.au> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Original-NNTP-Posting-Host: 203.220.42.253 Message-ID: <4093b2ae@news.comindico.com.au> X-Original-Trace: 2 May 2004 00:22:38 +1100, 203.220.42.253 Lines: 38 Date: Sat, 01 May 2004 14:22:39 GMT NNTP-Posting-Host: 203.194.27.1 X-Complaints-To: abuse@comindico.com.au X-Trace: news.optus.net.au 1083421359 203.194.27.1 (Sun, 02 May 2004 00:22:39 EST) NNTP-Posting-Date: Sun, 02 May 2004 00:22:39 EST Organization: Comindico Australia - reports relating to abuse should be sent to abuse@comindico.com.au Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!irazu.switch.ch!switch.ch!news.maxwell.syr.edu!news1.optus.net.au!optus!news.optus.net.au!53ab2750!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173094 Rob Storey wrote: > > Intrinsic wrote: > >>Hi, >> I am currently considering building a replica of the Altair 8800, >>however as I want it to be as faithful to the original as possible, I >>need to find a working Intel 8080 CPU somewhere (If not and 8080 and >>8080A would be ok but I'd prefer the original 8080 as that's what was >>used in the earliest models), (I know the Z-80 is virtually identical if >>not better however like I say I want it as faithful as possible), I am >>willing to ship from the US/Europe but Oceania would be better as I'm in >>Australia. >>Thanx >>Intrinsic > > > > I'm in Melbourne, and I'm almost certain that there's at least an 808A > lurking inside the piles of junk that I seem to accumulate. I'll have a > dig sometime over the next few days and let you know. > > What about building an EDUC-8? > I still have the book that compiled all the EA articles together. > > Cheers, > Rob Storey Hi, That'd be great, I'm in melb so if you do happen to find a chip floating around send me an email (please put [nospam] in the subject line coz otherwise I'm likely to bulk delete it.) I've never seen anything on the EDUC-8 floating around, it'd probably be interesting to have a look at it tho. Thanx Intrinsic ###### From: Intrinsic User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.5) Gecko/20031024 Debian/1.5-2 X-Accept-Language: en MIME-Version: 1.0 Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica References: <4092463b$1@news.comindico.com.au> In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Original-NNTP-Posting-Host: 203.220.42.253 Message-ID: <4093b3f8@news.comindico.com.au> X-Original-Trace: 2 May 2004 00:28:08 +1100, 203.220.42.253 Lines: 38 Date: Sat, 01 May 2004 14:28:22 GMT NNTP-Posting-Host: 203.194.27.1 X-Complaints-To: abuse@comindico.com.au X-Trace: news.optus.net.au 1083421702 203.194.27.1 (Sun, 02 May 2004 00:28:22 EST) NNTP-Posting-Date: Sun, 02 May 2004 00:28:22 EST Organization: Comindico Australia - reports relating to abuse should be sent to abuse@comindico.com.au Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!irazu.switch.ch!switch.ch!news.maxwell.syr.edu!news1.optus.net.au!optus!news.optus.net.au!53ab2750!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173095 Jack Peacock wrote: > "Intrinsic" wrote in message > news:4092463b$1@news.comindico.com.au... > >>Hi, >> I am currently considering building a replica of the Altair 8800, >>however as I want it to be as faithful to the original as possible >> > > While it may be worthwhile to build a replica for some kind of historical > perspective the fact remains the Altair design was not the high point of > technical design or layout. There was a reason the IMSAI used the plug in > front panel instead of 100 individual bus jumpers. That's why no one ever > copied the Altair version of the S-100. > > And what about the power supply? Will you stay with the original > underpowered unit or go with the 8800B size power supply? One of the first > add-on kits for the Altair was a replacement power supply by a company > called Parasitic Engineering (if ever a company had a more descriptive > name). > > You have a source for the Optimus case? That was one of the main selling > points used by MITS over the IMSAI. > Jack Peacock > > Hi, I'm primarily doing this as a learning experience for myself, the reason I selected it was because I KNEW it'd be a challenge, I do have the 8800B manual as well so I might take your advice on that and build the larger power supply. Again re: the case I don't currently have a source but I will search for one when/if I decide to go ahead with this project (I want to ascertain the availability of the internals first), if worse comes to worse I will construct a replica of that as well (I think I have just about enough photos from various angles to construct one.) Intrinsic ###### From: Intrinsic User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.5) Gecko/20031024 Debian/1.5-2 X-Accept-Language: en MIME-Version: 1.0 Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica References: <4092463b$1@news.comindico.com.au> In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Original-NNTP-Posting-Host: 203.220.42.253 Message-ID: <4093b4d6@news.comindico.com.au> X-Original-Trace: 2 May 2004 00:31:50 +1100, 203.220.42.253 Lines: 42 Date: Sat, 01 May 2004 14:31:51 GMT NNTP-Posting-Host: 203.194.27.1 X-Complaints-To: abuse@comindico.com.au X-Trace: news.optus.net.au 1083421911 203.194.27.1 (Sun, 02 May 2004 00:31:51 EST) NNTP-Posting-Date: Sun, 02 May 2004 00:31:51 EST Organization: Comindico Australia - reports relating to abuse should be sent to abuse@comindico.com.au Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!irazu.switch.ch!switch.ch!news.maxwell.syr.edu!news1.optus.net.au!optus!news.optus.net.au!53ab2750!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173097 Michael Black wrote: > Intrinsic (mreed13@hotmail.com) writes: > >>Hi, >> I am currently considering building a replica of the Altair 8800, >>however as I want it to be as faithful to the original as possible, I >>need to find a working Intel 8080 CPU somewhere (If not and 8080 and >>8080A would be ok but I'd prefer the original 8080 as that's what was >>used in the earliest models), (I know the Z-80 is virtually identical if >>not better however like I say I want it as faithful as possible), I am >>willing to ship from the US/Europe but Oceania would be better as I'm in >>Australia. >>Thanx >>Intrinsic >> > > The Z-80 would not be "virtually identical". > > A different brand of 8080, or the "A" or even a much later date code > on the device would still be an 8080. You could start with whatever's > cheap and available, and if you really wanted "authentic" search, and maybe > pay, for an 8080 of early vintage, and put it into the circuit. > > But if you use a Z-80 it's not an Altair 8800. The pinout is not the > same, the external circuitry (and maybe timing) is different. The only > way one could use a Z-80 in there is by changing the circuitry, or doing > as they would have done back then, a small board that plugs into the 8080 > socket. > > Michael > > That's interesting, I always thought that the Z-80 was based on the 8080 basically just a later manufacture by a different company, I have also heard about Z-80 boards for the Altair (on a few restoration sites and such), oh well maybe I'm wrong then ;o). I know it won't be a 'real' altair 8800 with the Z-80 thus the reason I'm searching for the original 8080, and if I was to use a z-80 I would be constructing a daughter board rather than butchering the original design. Thanx Intrinsic ###### From: Intrinsic User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.5) Gecko/20031024 Debian/1.5-2 X-Accept-Language: en MIME-Version: 1.0 Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica References: <4092463b$1@news.comindico.com.au> <33Akc.4758$0H1.486611@attbi_s54> In-Reply-To: <33Akc.4758$0H1.486611@attbi_s54> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Original-NNTP-Posting-Host: 203.220.42.253 Message-ID: <4093b52e$1@news.comindico.com.au> X-Original-Trace: 2 May 2004 00:33:18 +1100, 203.220.42.253 Lines: 25 Date: Sat, 01 May 2004 14:33:19 GMT NNTP-Posting-Host: 203.194.27.1 X-Complaints-To: abuse@comindico.com.au X-Trace: news.optus.net.au 1083421999 203.194.27.1 (Sun, 02 May 2004 00:33:19 EST) NNTP-Posting-Date: Sun, 02 May 2004 00:33:19 EST Organization: Comindico Australia - reports relating to abuse should be sent to abuse@comindico.com.au Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!switch.ch!takemy.news.telefonica.de!telefonica.de!newsfeed.media.kyoto-u.ac.jp!news1.optus.net.au!optus!news.optus.net.au!53ab2750!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173098 glen herrmannsfeldt wrote: > Intrinsic wrote: > >> Hi, >> I am currently considering building a replica of the Altair 8800, >> however as I want it to be as faithful to the original as possible, I >> need to find a working Intel 8080 CPU somewhere (If not and 8080 and >> 8080A would be ok but I'd prefer the original 8080 as that's what was >> used in the earliest models), > > > I think I still have the PC board plans. I was in high school when > it came out, so I couldn't really afford to buy one, but I did mail > in for the plans. It was a Popular Electronics project, so they would > always supply a mail address for the plans. > > -- glen > Hi, Where are you located? I'd love to get my hands on the original board patterns (I was going to make my own as close as I could to the originals) it'd be much easier. Thanx Intrinsic ###### From: "William" Newsgroups: alt.folklore.computers References: <4092463b$1@news.comindico.com.au> <4093b4d6@news.comindico.com.au> Subject: Re: Altair 8800 Replica Lines: 14 X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 6.00.2800.1409 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1409 Message-ID: Date: Sun, 02 May 2004 04:53:55 GMT NNTP-Posting-Host: 66.68.32.108 X-Complaints-To: abuse@rr.com X-Trace: fe2.texas.rr.com 1083473635 66.68.32.108 (Sat, 01 May 2004 23:53:55 CDT) NNTP-Posting-Date: Sat, 01 May 2004 23:53:55 CDT Organization: Road Runner High Speed Online http://www.rr.com Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!irazu.switch.ch!switch.ch!news.maxwell.syr.edu!news.moat.net!border1.nntp.sjc.giganews.com!border2.nntp.sjc.giganews.com!nntp.giganews.com!cyclone.austin.rr.com!fe2.texas.rr.com.POSTED!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173147 "Intrinsic" wrote in message news:4093b4d6@news.comindico.com.au... > That's interesting, I always thought that the Z-80 was based on the 8080 > basically just a later manufacture by a different company, It's an "improved" 8080 in that it is very code compatible with the 8080, but it's a different chip. Has two sets of registers, for starters (very handy for interrupts). Interfacing was simplified, IIRC. I programmed the 8080 in assembly but by the time I got a Z-80 I'd moved on to C so I don't really remember all the code extensions it had. -Wm ###### From: "William" Newsgroups: alt.folklore.computers References: <4092463b$1@news.comindico.com.au> <409394F6.4C67558B@optushome.com.au> <4093b2ae@news.comindico.com.au> Subject: Re: Altair 8800 Replica Lines: 17 X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 6.00.2800.1409 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1409 Message-ID: Date: Sun, 02 May 2004 05:00:28 GMT NNTP-Posting-Host: 66.68.32.108 X-Complaints-To: abuse@rr.com X-Trace: fe2.texas.rr.com 1083474028 66.68.32.108 (Sun, 02 May 2004 00:00:28 CDT) NNTP-Posting-Date: Sun, 02 May 2004 00:00:28 CDT Organization: Road Runner High Speed Online http://www.rr.com Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!irazu.switch.ch!switch.ch!newsfeed00.sul.t-online.de!t-online.de!border2.nntp.ash.giganews.com!nntp.giganews.com!elnk-atl-nf1!newsfeed.earthlink.net!cyclone.tampabay.rr.com!cyclone.austin.rr.com!fe2.texas.rr.com.POSTED!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173149 "Intrinsic" wrote in message news:4093b2ae@news.comindico.com.au... > Hi, > That'd be great, I'm in melb so if you do happen to find a chip > floating around send me an email (please put [nospam] in the subject > line coz otherwise I'm likely to bulk delete it.) If that doesn't work out, maybe you can get one from Jameco: http://www.jameco.com/cgi-bin/ncommerce3/ProductDisplay?prmenbr=91&prrfnbr=1962&cgrfnbr=604&ctgys=502;511;604; It's listed as "Refurbished" :-) Price is decent: $4.49 U.S. Some of the support chips may be harder to find, but they could be emulated. -Wm ###### From: Intrinsic User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.5) Gecko/20031024 Debian/1.5-2 X-Accept-Language: en MIME-Version: 1.0 Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica References: <4092463b$1@news.comindico.com.au> <409394F6.4C67558B@optushome.com.au> <4093b2ae@news.comindico.com.au> In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Original-NNTP-Posting-Host: 203.194.53.163 Message-ID: <4094ed52@news.comindico.com.au> X-Original-Trace: 2 May 2004 22:45:06 +1100, 203.194.53.163 Lines: 27 Date: Sun, 02 May 2004 12:45:06 GMT NNTP-Posting-Host: 203.194.27.1 X-Complaints-To: abuse@comindico.com.au X-Trace: news.optus.net.au 1083501906 203.194.27.1 (Sun, 02 May 2004 22:45:06 EST) NNTP-Posting-Date: Sun, 02 May 2004 22:45:06 EST Organization: Comindico Australia - reports relating to abuse should be sent to abuse@comindico.com.au Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!switch.ch!news.ip-plus.net!newsfeed.ip-plus.net!news.tesion.net!news.belwue.de!newsfeed01.sul.t-online.de!t-online.de!newsfeed.media.kyoto-u.ac.jp!news1.optus.net.au!optus!news.optus.net.au!53ab2750!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173161 William wrote: > "Intrinsic" wrote in message > news:4093b2ae@news.comindico.com.au... > > >>Hi, >> That'd be great, I'm in melb so if you do happen to find a chip >>floating around send me an email (please put [nospam] in the subject >>line coz otherwise I'm likely to bulk delete it.) > > > If that doesn't work out, maybe you can get one from Jameco: > http://www.jameco.com/cgi-bin/ncommerce3/ProductDisplay?prmenbr=91&prrfnbr=1962&cgrfnbr=604&ctgys=502;511;604; > > It's listed as "Refurbished" :-) Price is decent: $4.49 U.S. > > Some of the support chips may be harder to find, but they could > be emulated. -Wm > > Thanx heaps for that, now that I know I can get an 8080 the project is looking more feasable, far as support chips, I am having some issues there, the 8212, I think it may be a CIA of some discription but I'm not sure, any help you could offer there would be appreciated too. Thanx Intrinsic ###### From: Intrinsic User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.5) Gecko/20031024 Debian/1.5-2 X-Accept-Language: en MIME-Version: 1.0 Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica References: <4092463b$1@news.comindico.com.au> <409394F6.4C67558B@optushome.com.au> <4093b2ae@news.comindico.com.au> <4094ed52@news.comindico.com.au> In-Reply-To: <4094ed52@news.comindico.com.au> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Original-NNTP-Posting-Host: 203.194.53.163 Message-ID: <4094eec4@news.comindico.com.au> X-Original-Trace: 2 May 2004 22:51:16 +1100, 203.194.53.163 Lines: 36 Date: Sun, 02 May 2004 12:51:19 GMT NNTP-Posting-Host: 203.194.27.1 X-Complaints-To: abuse@comindico.com.au X-Trace: news.optus.net.au 1083502279 203.194.27.1 (Sun, 02 May 2004 22:51:19 EST) NNTP-Posting-Date: Sun, 02 May 2004 22:51:19 EST Organization: Comindico Australia - reports relating to abuse should be sent to abuse@comindico.com.au Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!switch.ch!news.ip-plus.net!newsfeed.ip-plus.net!news.tesion.net!news.belwue.de!news.ipv6.iphh.net!iphh.net!news0.de.colt.net!colt.net!peernews-us.colt.net!newsfeed.news2me.com!newsfeed3.easynews.com!easynews.com!easynews!border1.nntp.sjc.giganews.com!border2.nntp.sjc.giganews.com!nntp.giganews.com!news1.optus.net.au!optus!news.optus.net.au!53ab2750!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173165 Intrinsic wrote: > William wrote: > >> "Intrinsic" wrote in message >> news:4093b2ae@news.comindico.com.au... >> >> >>> Hi, >>> That'd be great, I'm in melb so if you do happen to find a chip >>> floating around send me an email (please put [nospam] in the subject >>> line coz otherwise I'm likely to bulk delete it.) >> >> >> >> If that doesn't work out, maybe you can get one from Jameco: >> http://www.jameco.com/cgi-bin/ncommerce3/ProductDisplay?prmenbr=91&prrfnbr=1962&cgrfnbr=604&ctgys=502;511;604; >> >> >> It's listed as "Refurbished" :-) Price is decent: $4.49 U.S. >> >> Some of the support chips may be harder to find, but they could >> be emulated. -Wm >> >> > Thanx heaps for that, now that I know I can get an 8080 the project is > looking more feasable, far as support chips, I am having some issues > there, the 8212, I think it may be a CIA of some discription but I'm not > sure, any help you could offer there would be appreciated too. > Thanx > Intrinsic > Scratch the 8212, Jameco has them and they're some kind of buffer device (Just waiting on the datasheet d/l ;o) ). Thanx Intrinsic ###### From: ace join_to ware@iinet.net.au (Tony Epton) Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica Date: Mon, 03 May 2004 12:19:06 GMT Organization: Aceware Programming Pty Ltd Message-ID: <409637a8.651468@news.m.iinet.net.au> References: <4092463b$1@news.comindico.com.au> <409394F6.4C67558B@optushome.com.au> X-Newsreader: Forte Free Agent 1.21/32.243 Lines: 17 NNTP-Posting-Host: 203.59.54.231 X-Trace: 1083586654 freenews.iinet.net.au 4321 203.59.54.231 Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!irazu.switch.ch!switch.ch!HSNX.atgi.net!newsfeed.iinet.net.au!newsfeed.iinet.net.au!freenews.iinet.net.au!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173256 >What about building an EDUC-8? >I still have the book that compiled all the EA articles together. Any idea where you get the edge connectors for the EDUC-8 ? I bought the first two boards from RCS but came to a dead stop when attempting to source the connectors - I'm sure they were very cheap and plentiful back in 1973 - but I cannot find any in Australia now. Many apologies if I already have asked this question on this group - I REALLY AM having trouble with my memory. Many thanks Tony Epton ###### Message-ID: <4096551A.A06A9758@optushome.com.au> Date: Tue, 04 May 2004 00:20:10 +1000 From: Rob Storey Organization: @Home X-Mailer: Mozilla 4.6 [en-gb]C-AtHomeI0407 (Win98; I) X-Accept-Language: en-GB,en,en-* MIME-Version: 1.0 Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica References: <4092463b$1@news.comindico.com.au> <409394F6.4C67558B@optushome.com.au> <409637a8.651468@news.m.iinet.net.au> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Lines: 43 NNTP-Posting-Host: 211.28.100.186 X-Trace: 1083594166 440 211.28.100.186 Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!irazu.switch.ch!switch.ch!news.maxwell.syr.edu!news1.optus.net.au!optus!newsfeeder.syd.optusnet.com.au!news.optusnet.com.au!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173271 Hi Tony, > Any idea where you get the edge connectors for the EDUC-8 ? > > I bought the first two boards from RCS but came to a dead stop when > attempting to source the connectors - I'm sure they were very cheap > and plentiful back in 1973 - but I cannot find any in Australia now. I built one back in '76, no idea where or when it went, but it's gone now. Although heaps of fun, it was incredibly unreliable, mostly due to the edge connectors. The boards didn't have gold fingers, and they weren't supported well, so they tended to flap about, causing frequent problems. If I came at this project again (which I'd love to, but the last thing I need is yet another project in progress), I'd do a few things differently:- Although it's great that RCS still make the boards, they're expensive. I'd scan the artwork, touch them up, make any desired mods, then print it on laser and make them using the "Toner copier method" (google that for more info). I'd find a different connection method than the edge connectors, maybe IDC headers stuck on the board so that there's a row of pins on each side of the board, and appropriate sockets on the mother board. The pitch would also need adjusting during the touch up stage. That could be done to enable use of different edge connectors as well. I'd change the memory chip pin out to suit a 2102 instead of the ridiculous bipolar (93415?) original specified (expensive and about 1000 times faster than needed). Maybe even a larger static RAM chip (probably on a daughter board) to provide large memory space and the associated bank select logic) A friend of mine implemented bank switching on his EDUC-8 way back then. Probably many other mods would come to mind if I really looked into it. RS232, larger bus for more boards, etc. etc... It could be made into a machine that could do something useful, rather than being just a toy. Cheers, Rob Storey ###### Message-ID: <40965B7A.1E31A1CA@optushome.com.au> Date: Tue, 04 May 2004 00:47:22 +1000 From: Rob Storey Organization: @Home X-Mailer: Mozilla 4.6 [en-gb]C-AtHomeI0407 (Win98; I) X-Accept-Language: en-GB,en,en-* MIME-Version: 1.0 Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica References: <4092463b$1@news.comindico.com.au> <409394F6.4C67558B@optushome.com.au> <409637a8.651468@news.m.iinet.net.au> <4096551A.A06A9758@optushome.com.au> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Lines: 35 NNTP-Posting-Host: 211.28.100.186 X-Trace: 1083595795 12033 211.28.100.186 Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!switch.ch!news.imp.ch!news.imp.ch!news.linkpendium.com!border1.nntp.sjc.giganews.com!border2.nntp.sjc.giganews.com!nntp.giganews.com!news1.optus.net.au!optus!newsfeeder.syd.optusnet.com.au!news.optusnet.com.au!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173273 Just thinking aloud here... > If I came at this project again ..., I'd do a few things differently... > It could be made into a machine that could do something useful... But then I think, "Why would I want to do this (or the Altair replica)?" The main answer I come up with is "for Das Blinken Lights". But I could get that by designing and building a whole new computer from the ground up, while also satisfying my "frustrated computer architect" issues. Of course, the lack of any exiting software would then be a huge problem. I suppose the best compromise in terms of effort required, usefulness of the end result and warm satisfied feeling would be:- * blinken lights - a given, must have this! * an existing architecture for which software is available. * minimal electronics, discrete IC's (or transistors!) is too much work. So a fast embedded MCU running microcode and driving the console display, with an old IDE hard disk and serial port talking to a PC, etc. Of course I could just get my PDP-11/05 working (another project), but I'd also like something mesmerizing that can easily sit on a desk, or hang from a wall, rather than having a whole rack of equipment powered up (and a bit quieter too). And gee, I'm also working on an IBM 7094 emulator - hmmm... Rob Storey Cheers, Rob Storey ###### NNTP-Posting-Date: Mon, 03 May 2004 12:29:31 -0500 From: "William" Newsgroups: alt.folklore.computers References: <4092463b$1@news.comindico.com.au> <409394F6.4C67558B@optushome.com.au> <4093b2ae@news.comindico.com.au> <4094ed52@news.comindico.com.au> <4094eec4@news.comindico.com.au> Subject: Re: Altair 8800 Replica Date: Mon, 3 May 2004 12:29:30 -0500 X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 6.00.2800.1409 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2800.1409 Message-ID: Lines: 17 X-Trace: sv3-1jr4kq8eJDzL67qnY7tRK+oGIHQ42SCEecTcXG8Z/qzhMX9xw1/KjqFYx80chgZN7jkQIThLRnhH3U0!T5dznzHMd9MCOhAimOQ/0n0uQX2NAjY2CyNAOifVaTNtO7GerXj84JoxvUummw== X-Complaints-To: abuse@giganews.com X-DMCA-Notifications: http://www.giganews.com/info/dmca.html X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.1 Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!irazu.switch.ch!switch.ch!in.100proofnews.com!in.100proofnews.com!border2.nntp.ash.giganews.com!border1.nntp.ash.giganews.com!nntp.giganews.com!local1.nntp.ash.giganews.com!news.giganews.com.POSTED!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173284 "Intrinsic" wrote in message news:4094eec4@news.comindico.com.au... > > > Scratch the 8212, Jameco has them and they're some kind of buffer device > (Just waiting on the datasheet d/l ;o) ). > Thanx > Intrinsic I'll test my memory and say it's a buffered latch? I think they called it a PIA - Parallel Interface Adapter - in a 24 pin wide dip package. (The 74xxx 8-bit latch/buffer chips in 20-pin standard width dips had not come out at that time.) I think there was also a clock generator chip, if the 8212 isn't the PIA, it might be that. -Wm ###### From: Sam Seiber Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica Date: Mon, 03 May 2004 14:58:16 -0600 Organization: There are no numbers in my e-mail addy Message-ID: <4096B268.7B48@sbseiber.com> X-Mailer: Mozilla 3.01Gold (Win95; I) MIME-Version: 1.0 References: <4092463b$1@news.comindico.com.au> <409394F6.4C67558B@optushome.com.au> <4093b2ae@news.comindico.com.au> <4094ed52@news.comindico.com.au> <4094eec4@news.comindico.com.au> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Complaints-To: abuse@supernews.com Lines: 28 Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!irazu.switch.ch!switch.ch!news.maxwell.syr.edu!sn-xit-03!sn-xit-01!sn-post-01!supernews.com!news.supernews.com!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173316 William wrote: > > "Intrinsic" wrote in message > news:4094eec4@news.comindico.com.au... > > > > > Scratch the 8212, Jameco has them and they're some kind of buffer device > > (Just waiting on the datasheet d/l ;o) ). > > Thanx > > Intrinsic > > I'll test my memory and say it's a buffered latch? I think they called it a > PIA - Parallel Interface Adapter - in a 24 pin wide dip package. (The > 74xxx 8-bit latch/buffer chips in 20-pin standard width dips had not > come out at that time.) > > I think there was also a clock generator chip, if the 8212 isn't the PIA, > it might be that. -Wm The original Altair didn't use the clock generator chip. IIRC, when MITS designed their machine, the Intel clock generator wasn't yet out. So, MITS used some one shots (74123's) to generate the clock. The 8212 isn't much more than an 8 bit latch to generate some bus signals (memory read, I/O, interrupt, etc). Sam ###### From: et472@FreeNet.Carleton.CA (Michael Black) Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica Date: 3 May 2004 21:00:00 GMT Organization: The National Capital FreeNet Lines: 36 Message-ID: References: <4092463b$1@news.comindico.com.au> <409394F6.4C67558B@optushome.com.au> <4093b2ae@news.comindico.com.au> <4094ed52@news.comindico.com.au> <4094eec4@news.comindico.com.au> <4096B268.7B48@sbseiber.com> Reply-To: et472@FreeNet.Carleton.CA (Michael Black) NNTP-Posting-Host: smeagol.ncf.ca X-Trace: freenet9.carleton.ca 1083618000 11027 134.117.136.48 (3 May 2004 21:00:00 GMT) X-Complaints-To: complaints@ncf.ca NNTP-Posting-Date: 3 May 2004 21:00:00 GMT X-Given-Sender: et472@smeagol.ncf.ca (Michael Black) Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!switch.ch!news.ip-plus.net!newsfeed.ip-plus.net!news.tesion.net!news.belwue.de!news.tu-darmstadt.de!newsfeed.freenet.de!216.196.98.140.MISMATCH!border1.nntp.ash.giganews.com!nntp.giganews.com!news.glorb.com!news-spur1.glorb.com!news.kjsl.com!xcski.com!freenet-news!FreeNet.Carleton.CA!et472 Xref: redlance.franklin.ch alt.folklore.computers:173317 Sam Seiber (Sam.Seiber1234@sbseiber.com) writes: > William wrote: >> >> "Intrinsic" wrote in message >> news:4094eec4@news.comindico.com.au... >> > > >> > Scratch the 8212, Jameco has them and they're some kind of buffer device >> > (Just waiting on the datasheet d/l ;o) ). >> > Thanx >> > Intrinsic >> >> I'll test my memory and say it's a buffered latch? I think they called it a >> PIA - Parallel Interface Adapter - in a 24 pin wide dip package. (The >> 74xxx 8-bit latch/buffer chips in 20-pin standard width dips had not >> come out at that time.) >> >> I think there was also a clock generator chip, if the 8212 isn't the PIA, >> it might be that. -Wm > > The original Altair didn't use the clock generator chip. IIRC, when > MITS > designed their machine, the Intel clock generator wasn't yet out. So, > MITS > used some one shots (74123's) to generate the clock. The 8212 isn't > much > more than an 8 bit latch to generate some bus signals (memory read, I/O, > interrupt, etc). > > Sam And weren't there problems with the clock generator MITS used in the Altair? I can picture an article in a very early issue of Byte that addresses some problem with the clock generator, though I'm not sure of the problem. Michael ###### From: Sam Seiber Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica Date: Mon, 03 May 2004 15:31:49 -0600 Organization: There are no numbers in my e-mail addy Message-ID: <4096BA45.6EAF@sbseiber.com> X-Mailer: Mozilla 3.01Gold (Win95; I) MIME-Version: 1.0 References: <4092463b$1@news.comindico.com.au> <409394F6.4C67558B@optushome.com.au> <4093b2ae@news.comindico.com.au> <4094ed52@news.comindico.com.au> <4094eec4@news.comindico.com.au> <4096B268.7B48@sbseiber.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Complaints-To: abuse@supernews.com Lines: 15 Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!irazu.switch.ch!switch.ch!news.maxwell.syr.edu!sn-xit-03!sn-xit-01!sn-post-01!supernews.com!news.supernews.com!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173324 Michael Black wrote: > And weren't there problems with the clock generator MITS used in the Altair? > I can picture an article in a very early issue of Byte that addresses some > problem with the clock generator, though I'm not sure of the problem. > > Michael Damn I wish I remember. I have an Altair. It isn't working, and I think it is a clock problem. The 8080 had a 2 phase clock, and the two phases had to overlap "just right" for the 8080 to run. My really old brain can't remember if the voltage of the clock was non-TTL. I have some memory of 8 volts, but that just could be organic bit rot on my part. Sam ###### From: ace join_to ware@iinet.net.au (Tony Epton) Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica Date: Mon, 03 May 2004 23:07:04 GMT Organization: Aceware Programming Pty Ltd Message-ID: <4096d063.266046@news.m.iinet.net.au> References: <4092463b$1@news.comindico.com.au> <409394F6.4C67558B@optushome.com.au> <409637a8.651468@news.m.iinet.net.au> <4096551A.A06A9758@optushome.com.au> <40965B7A.1E31A1CA@optushome.com.au> X-Newsreader: Forte Free Agent 1.21/32.243 Lines: 7 NNTP-Posting-Host: 203.59.54.231 X-Trace: 1083625530 freenews.iinet.net.au 16593 203.59.54.231 Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!switch.ch!news.ip-plus.net!newsfeed.ip-plus.net!news.tesion.net!news.belwue.de!news-stu1.dfn.de!news-han1.dfn.de!HSNX.atgi.net!newsfeed.iinet.net.au!newsfeed.iinet.net.au!freenews.iinet.net.au!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173336 >And gee, I'm also working on an IBM 7094 emulator - hmmm... > So many projects - so little time :-) Best wishes Tony ###### From: ace join_to ware@iinet.net.au (Tony Epton) Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica Date: Mon, 03 May 2004 23:14:08 GMT Organization: Aceware Programming Pty Ltd Message-ID: <4096d0dc.387265@news.m.iinet.net.au> References: <4092463b$1@news.comindico.com.au> <409394F6.4C67558B@optushome.com.au> <409637a8.651468@news.m.iinet.net.au> <4096551A.A06A9758@optushome.com.au> X-Newsreader: Forte Free Agent 1.21/32.243 Lines: 25 NNTP-Posting-Host: 203.59.54.231 X-Trace: 1083625956 freenews.iinet.net.au 16592 203.59.54.231 Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!switch.ch!takemy.news.telefonica.de!telefonica.de!npeer.de.kpn-eurorings.net!news.moat.net!border1.nntp.sjc.giganews.com!border2.nntp.sjc.giganews.com!nntp.giganews.com!cyclone-sf.pbi.net!64.42.15.2!HSNX.atgi.net!newsfeed.iinet.net.au!newsfeed.iinet.net.au!freenews.iinet.net.au!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173339 >If I came at this project again (which I'd love to, but the last thing I >need is yet another project in progress), I'd do a few things >differently:- > >Although it's great that RCS still make the boards, they're expensive. >I'd scan the artwork, touch them up, make any desired mods, then print >it on laser and make them using the "Toner copier method" (google that >for more info). > >I'd find a different connection method than the edge connectors, maybe >IDC headers stuck on the board so that there's a row of pins on each >side of the board, and appropriate sockets on the mother board. The >pitch would also need adjusting during the touch up stage. That could be >done to enable use of different edge connectors as well. I guess MY weird, perverse inclinination would be to try to build something as close to the original as possible - including it's technical failings in all their glory. Though - if you pressed me for a reason - I'd never be able to justify it. Thanks for all the great ideas. Best wishes Tony ###### NNTP-Posting-Date: Mon, 03 May 2004 18:51:30 -0500 From: "Jack Peacock" Newsgroups: alt.folklore.computers References: <4092463b$1@news.comindico.com.au> <409394F6.4C67558B@optushome.com.au> <4093b2ae@news.comindico.com.au> <4094ed52@news.comindico.com.au> <4094eec4@news.comindico.com.au> <4096B268.7B48@sbseiber.com> Subject: Re: Altair 8800 Replica Date: Mon, 3 May 2004 16:51:30 -0700 X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 6.00.2800.1409 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1409 Message-ID: Lines: 28 NNTP-Posting-Host: 66.18.133.20 X-Trace: sv3-59NmvX/GXvQv5ltmk3Xfm5xK67TR6Pfd3qAdr7Xh2ARfUqhWzqGcuB3iB2KmAn69ss4yfZvem2w4j09!l0pBS7IfwlJ3pGEwmRuAB9B6oEwDq51vQmoh1obVog6n/pEcoQF7UEMS1p/9AQKaXywc29rmQfkC!c7Q= X-Complaints-To: abuse@mpowercom.net X-DMCA-Complaints-To: abuse@mpowercom.net X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.1 Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!switch.ch!news.imp.ch!news.imp.ch!209.11.36.156.MISMATCH!nntp-server.pubsub.com!border1.nntp.ash.giganews.com!nntp.giganews.com!local1.nntp.ash.giganews.com!nntp.mpowercom.net!news.mpowercom.net.POSTED!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173342 "Michael Black" wrote in message news:c76bsg$aoj$1@freenet9.carleton.ca... > >> I'll test my memory and say it's a buffered latch? I think they called it a > >> PIA - Parallel Interface Adapter - in a 24 pin wide dip package. (The > >> 74xxx 8-bit latch/buffer chips in 20-pin standard width dips had not > >> come out at that time.) > >> > And weren't there problems with the clock generator MITS used in the Altair? > I can picture an article in a very early issue of Byte that addresses some > problem with the clock generator, though I'm not sure of the problem. > The 8212 was a TTL 8-bit latch in a 600mil DIP package. It was essentially the first version of a parallel port chip for 8080s, until the 8255 came out. The MITS 4KB dynamic ram board had clocking problems due to the marginal one-shots used to control RAS to CAS timing. Sometimes they worked, sometimes they worked for a while, sometimes they didn't work at all. The reputation of those boards went a long way toward keeping DRAM out of micros for years as the technology was thought to be somehow inherently flawed or too complex for small systems. Jack Peacock (who personally tossed one in the trashcan and replaced it with an IMSAI 4KB static) ###### From: et472@FreeNet.Carleton.CA (Michael Black) Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica Date: 4 May 2004 00:43:47 GMT Organization: The National Capital FreeNet Lines: 22 Message-ID: References: <4092463b$1@news.comindico.com.au> <409394F6.4C67558B@optushome.com.au> <4093b2ae@news.comindico.com.au> <4094ed52@news.comindico.com.au> <4094eec4@news.comindico.com.au> <4096B268.7B48@sbseiber.com> <4096BA45.6EAF@sbseiber.com> Reply-To: et472@FreeNet.Carleton.CA (Michael Black) NNTP-Posting-Host: smeagol.ncf.ca X-Trace: freenet9.carleton.ca 1083631427 7717 134.117.136.48 (4 May 2004 00:43:47 GMT) X-Complaints-To: complaints@ncf.ca NNTP-Posting-Date: 4 May 2004 00:43:47 GMT X-Given-Sender: et472@smeagol.ncf.ca (Michael Black) Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!switch.ch!news.ip-plus.net!newsfeed.ip-plus.net!news.tesion.net!news.belwue.de!news.ipv6.iphh.net!iphh.net!news.osn.de!border1.nntp.ash.giganews.com!nntp.giganews.com!priapus.visi.com!orange.octanews.net!news-out.visi.com!petbe.visi.com!news.octanews.net!nntp1.roc.gblx.net!nntp.gblx.net!nntp.gblx.net!xcski.com!freenet-news!FreeNet.Carleton.CA!et472 Xref: redlance.franklin.ch alt.folklore.computers:173360 Sam Seiber (Sam.Seiber1234@sbseiber.com) writes: > Michael Black wrote: >> And weren't there problems with the clock generator MITS used in the Altair? >> I can picture an article in a very early issue of Byte that addresses some >> problem with the clock generator, though I'm not sure of the problem. >> >> Michael > > Damn I wish I remember. I have an Altair. It isn't working, and I > think > it is a clock problem. The 8080 had a 2 phase clock, and the two phases > had to overlap "just right" for the 8080 to run. My really old brain > can't remember if the voltage of the clock was non-TTL. I have some > memory of 8 volts, but that just could be organic bit rot on my part. > > Sam I'll see if I can dig out what I'm thinking of. I know I can find it, just not sure if I'll get around to, or remember, to look for it. Michael ###### Message-ID: <40970BE6.61238E54@yahoo.com> From: CBFalconer Reply-To: cbfalconer@worldnet.att.net Organization: Ched Research X-Mailer: Mozilla 4.75 [en] (Win98; U) X-Accept-Language: en MIME-Version: 1.0 Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica References: <4092463b$1@news.comindico.com.au> <409394F6.4C67558B@optushome.com.au> <4093b2ae@news.comindico.com.au> <4094ed52@news.comindico.com.au> <4094eec4@news.comindico.com.au> <4096B268.7B48@sbseiber.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Lines: 26 Date: Tue, 04 May 2004 03:26:43 GMT NNTP-Posting-Host: 12.76.140.29 X-Complaints-To: abuse@worldnet.att.net X-Trace: bgtnsc05-news.ops.worldnet.att.net 1083641203 12.76.140.29 (Tue, 04 May 2004 03:26:43 GMT) NNTP-Posting-Date: Tue, 04 May 2004 03:26:43 GMT Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!irazu.switch.ch!switch.ch!news.maxwell.syr.edu!wn14feed!worldnet.att.net!bgtnsc05-news.ops.worldnet.att.net.POSTED!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173363 Michael Black wrote: > Sam Seiber (Sam.Seiber1234@sbseiber.com) writes: > ... snip ... >> >> The original Altair didn't use the clock generator chip. IIRC, >> when MITS designed their machine, the Intel clock generator >> wasn't yet out. So, MITS used some one shots (74123's) to >> generate the clock. The 8212 isn't much more than an 8 bit >> latch to generate some bus signals (memory read, I/O, interrupt, >> etc). > > And weren't there problems with the clock generator MITS used in > the Altair? I can picture an article in a very early issue of > Byte that addresses some problem with the clock generator, though > I'm not sure of the problem. Even then the use of one-shots in the clock generator was unforgiveably bad. -- "I'm a war president. I make decisions here in the Oval Office in foreign policy matters with war on my mind." - Bush. "Churchill and Bush can both be considered wartime leaders, just as Secretariat and Mr Ed were both horses." - James Rhodes. ###### From: "Howard Long" Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica Date: Tue, 4 May 2004 13:14:20 +0000 (UTC) Organization: BT Openworld Lines: 46 Message-ID: References: <4092463b$1@news.comindico.com.au> <4093b4d6@news.comindico.com.au> NNTP-Posting-Host: dial81-135-140-139.in-addr.btopenworld.com X-Trace: hercules.btinternet.com 1083676460 607 81.135.140.139 (4 May 2004 13:14:20 GMT) X-Complaints-To: news-complaints@lists.btinternet.com NNTP-Posting-Date: Tue, 4 May 2004 13:14:20 +0000 (UTC) X-Newsreader: Microsoft Outlook Express 6.00.2800.1409 X-MSMail-Priority: Normal X-Priority: 3 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1409 Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!irazu.switch.ch!switch.ch!newsfeed00.sul.t-online.de!t-online.de!diablo.theplanet.net!zen.net.uk!demorgan.zen.co.uk!194.72.9.35.MISMATCH!news-peer1!btnet-feed5!btnet!news.btopenworld.com!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173393 "William" wrote in message news:D9%kc.44042$hR1.3065@fe2.texas.rr.com... > "Intrinsic" wrote in message > news:4093b4d6@news.comindico.com.au... > > > That's interesting, I always thought that the Z-80 was based on the 8080 > > basically just a later manufacture by a different company, > > It's an "improved" 8080 in that it is very code compatible with the 8080, > but it's a different chip. Has two sets of registers, for starters (very > handy > for interrupts). Interfacing was simplified, IIRC. I programmed the 8080 > in assembly but by the time I got a Z-80 I'd moved on to C so I don't > really remember all the code extensions it had. -Wm > The Z80 and 8080 are not pin compatible either. The 8080 also needed additional power supplies (+12V and -5V IIRC) whereas the Z80 managed with just +5V. The native interrupts operate differently too, although I do not know how the S-100 bus implemented this: there may have been a similar One 'enhancement' was an almost useless dynamic RAM refresh mechanism on the Z80 - by the time you'd added the glue logic necessary to make it work you might as well have put your own refresh logic in there from scratch as the timing never seemed compatible with any dynamic RAM chips you could purchase. The Sinclair/Timex ZX80 and ZX81 used the Z80's program addressable refresh counter and vectored interrupt register to provide video refresh. A real ingenious hack if ever I saw one. There was also the addition of the 16 bit IX and IY registers allowing indirect indexed addressing. This was useful, but back in the days when programmers cared about how much CPU and clock cycles their programs took they often found using the standard 8080 16 bit registers more efficient. The Z80 has some nice enhancements like the looping DJNZ instruction. Plus there were the multi-byte instructions, as well as 16 bit addition and subtraction with carry, many more shift/rotate options, indirect I/O instructions, bitwise instructions, and short relative jumps. IIRC the main (only?) software incompatibility surrounded the way the parity flag worked: it was used on the Z80 as a way to determine whether the previous addition or subtraction instruction had overflowed. Otherwise logical operations affected the parity flag identically. Kind Regards, Howard ###### Message-ID: <4097AC08.16DD7337@optushome.com.au> Date: Wed, 05 May 2004 00:43:20 +1000 From: Rob Storey Organization: @Home X-Mailer: Mozilla 4.6 [en-gb]C-AtHomeI0407 (Win98; I) X-Accept-Language: en-GB,en,en-* MIME-Version: 1.0 Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica References: <4092463b$1@news.comindico.com.au> <409394F6.4C67558B@optushome.com.au> <4093b2ae@news.comindico.com.au> <4094ed52@news.comindico.com.au> <4094eec4@news.comindico.com.au> <4096B268.7B48@sbseiber.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Lines: 24 NNTP-Posting-Host: 211.28.100.186 X-Trace: 1083681948 28242 211.28.100.186 Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!switch.ch!news.imp.ch!news.imp.ch!news.moat.net!border1.nntp.sjc.giganews.com!border2.nntp.sjc.giganews.com!nntp.giganews.com!news1.optus.net.au!optus!newsfeeder.syd.optusnet.com.au!news.optusnet.com.au!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173400 > The 8212 was a TTL 8-bit latch in a 600mil DIP package. It was essentially > the first version of a parallel port chip for 8080s, until the 8255 came > out. But didn't need any programming, so was a handy chip for holding a byte generally, like when the main data bus wasn't right nearby, or if it had to be working before the CPU could program it. IIRC the clock generator chips for these early micro's (8080 & 6800) used non-TTL levels - they drove closer and harder to the +5v rail, as required by those CPUs. > The MITS 4KB dynamic ram board had clocking problems due to the marginal > one-shots used to control RAS to CAS timing. Sometimes they worked, > sometimes they worked for a while, sometimes they didn't work at all. The > reputation of those boards went a long way toward keeping DRAM out of micros > for years as the technology was thought to be somehow inherently flawed or > too complex for small systems. I remember the standard explanation for the difference between Static and Dynamic RAM in those days, it was: "Static RAM works, and Dynamic RAM doesn't!" Rob Storey ###### NNTP-Posting-Date: Tue, 04 May 2004 14:57:06 -0500 From: "Bill Leary" Newsgroups: alt.folklore.computers References: <408e589b$0$28898$61fed72c@news.rcn.com> <7d4190pt88993brl7sqppff1g8ugafqjk2@4ax.com> <42e2905tu557hrutebi91el0s8rr1pujvc@4ax.com> <4092685f$0$28932$61fed72c@news.rcn.com> <40979035$0$3029$61fed72c@news.rcn.com> Subject: Re: were dumb terminals actually so dumb??? Date: Tue, 4 May 2004 16:00:46 -0400 X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 6.00.2800.1409 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1409 Message-ID: Lines: 45 X-Trace: sv3-mCFfrdhrQlDSP4WSFBmvlnOeO+duAwWAIQXjzvBVoh/RiA7W+mmkOJZOnZixNeGzPtfK+TGuf6REnQo!QkTp0LjE4IkpGhGdalTTW0QFMLlrl5xIdzut85Huq7Db4pTsPqb3aXT6i8Q= X-Complaints-To: abuse@giganews.com X-DMCA-Notifications: http://www.giganews.com/info/dmca.html X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.1 Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!irazu.switch.ch!switch.ch!newsfeed00.sul.t-online.de!t-online.de!border2.nntp.ash.giganews.com!border1.nntp.ash.giganews.com!nntp.giganews.com!local1.nntp.ash.giganews.com!news.giganews.com.POSTED!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173428 wrote in message news:40979035$0$3029$61fed72c@news.rcn.com... > In article , > >I made peace with Murphy years ago. I allowed as that he'd always win, he > >allowed as that I'd always loose, and we got along fine after that. > > That's no fun. Part of the game is to figure out all possible > Murphy events, code in recoveries, then hold breath. Well, I did learn early on that all switch statements (or equivalents in other languages, or if/elseif/else/or what have you) must end like this: default: /* All cases are covered, so this can't ever happen */ cant_happen(23); } then elsewhere I've got /* ------------------------- * Murphy handler. * If it absolutely, positively, can not ever happen... it will. */ void cant_happen(int which_one) { fprintf(stderr, "\n* * * Can't ever happen #%d, just did * * *\n", which_one); fflush(stderr); exit(-1); } Or, if the program isn't user oriented, save to a log file or some such. In some cases a CMOS location. You get the idea. If Murphy is in rare form he'll screw up the print out or the log file, but he isn't usually THAT nasty. And if so, I can usually put a break point on the function with the debugger. If the program is for "real" users, I can pretty up the message to something more user acceptable like "Error #%d encountered, please contact support" If I'm feeling particularly whimsical, I'll call the function itself "murphy" or "murphy_handler." - Bill ###### From: Pete Fenelon Newsgroups: alt.folklore.computers Subject: Re: were dumb terminals actually so dumb??? Date: Tue, 4 May 2004 21:46:15 +0100 Organization: Utility Muffin Research Kitchen Lines: 58 Message-ID: References: <408e589b$0$28898$61fed72c@news.rcn.com> <7d4190pt88993brl7sqppff1g8ugafqjk2@4ax.com> <42e2905tu557hrutebi91el0s8rr1pujvc@4ax.com> <4092685f$0$28932$61fed72c@news.rcn.com> <40979035$0$3029$61fed72c@news.rcn.com> NNTP-Posting-Host: host81-152-17-202.range81-152.btcentralplus.com (81.152.17.202) X-Trace: news.uni-berlin.de 1083703625 1270428 I 81.152.17.202 ([203095]) X-Orig-Path: not-for-mail User-Agent: tin/1.7.4-20040225 ("Benbecula") (UNIX) (Linux/2.4.19 (i686)) Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!irazu.switch.ch!switch.ch!newsfeed00.sul.t-online.de!newsfeed01.sul.t-online.de!t-online.de!fu-berlin.de!uni-berlin.de!host81-152-17-202.range81-152.btcentralplus.COM!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173439 Bill Leary wrote: > wrote in message > news:40979035$0$3029$61fed72c@news.rcn.com... >> In article , >> >I made peace with Murphy years ago. I allowed as that he'd always win, > he >> >allowed as that I'd always loose, and we got along fine after that. >> >> That's no fun. Part of the game is to figure out all possible >> Murphy events, code in recoveries, then hold breath. > > Well, I did learn early on that all switch statements (or equivalents in > other languages, or if/elseif/else/or what have you) must end like this: > > default: /* All cases are covered, so this can't ever happen */ > cant_happen(23); > } > > then elsewhere I've got > > /* ------------------------- > * Murphy handler. > * If it absolutely, positively, can not ever happen... it will. > */ > void cant_happen(int which_one) { > fprintf(stderr, "\n* * * Can't ever happen #%d, just did * * *\n", > which_one); > fflush(stderr); > exit(-1); > } > > Or, if the program isn't user oriented, save to a log file or some such. In > some cases a CMOS location. You get the idea. > I've always preferred void cant_happen (const char *f, int l) { /* do whatever you need to lock out interrupts! - eg asm("di"); */ /* do whatever logging needs to be done... eg printf() */ /* place a breakpoint here on an embedded system */ for(;;); } "Can't happens" are then put in as cant_happen(__FILE, __LINE__); so I can see where something that couldn't happen happened ;) If you're modern you could even make it char *, char *, int, and add __FUNCTION__, but I'm a luddite ;) pete -- pete@fenelon.com "there's no room for enigmas in built-up areas" ###### X-Trace-PostClient-IP: 68.147.131.211 From: Brian Inglis Newsgroups: alt.folklore.computers Subject: Re: were dumb terminals actually so dumb??? Organization: Systematic Software Reply-To: Brian.Inglis@SystematicSw.ab.ca Message-ID: <133g9053bo3upfgkvcn2o89gm83mm009pk@4ax.com> References: <408e589b$0$28898$61fed72c@news.rcn.com> <7d4190pt88993brl7sqppff1g8ugafqjk2@4ax.com> <42e2905tu557hrutebi91el0s8rr1pujvc@4ax.com> <4092685f$0$28932$61fed72c@news.rcn.com> <40979035$0$3029$61fed72c@news.rcn.com> X-Newsreader: Forte Agent 1.93/32.576 English (American) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Lines: 19 Date: Tue, 04 May 2004 21:37:03 GMT NNTP-Posting-Host: 24.71.223.147 X-Complaints-To: abuse@shaw.ca X-Trace: pd7tw2no 1083706623 24.71.223.147 (Tue, 04 May 2004 15:37:03 MDT) NNTP-Posting-Date: Tue, 04 May 2004 15:37:03 MDT Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!irazu.switch.ch!switch.ch!solnet.ch!solnet.ch!newsfeed.mountaincable.net!news.glorb.com!news3.optonline.net!pd7cy1no!shaw.ca!pd7tw2no.POSTED!53ab2750!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173448 On Tue, 4 May 2004 21:46:15 +0100 in alt.folklore.computers, Pete Fenelon wrote: >"Can't happens" are then put in as > >cant_happen(__FILE, __LINE__); > >so I can see where something that couldn't happen happened ;) > >If you're modern you could even make it char *, char *, int, and add >__FUNCTION__, but I'm a luddite ;) ^^^^^^^^^^^^ __func__ -- __FUNCTION__ and __PRETTY_FUNCTION__ are GCCisms -- Thanks. Take care, Brian Inglis Calgary, Alberta, Canada Brian.Inglis@CSi.com (Brian dot Inglis at SystematicSw dot ab dot ca) fake address use address above to reply ###### NNTP-Posting-Date: Tue, 04 May 2004 16:34:30 -0500 From: "Bill Leary" Newsgroups: alt.folklore.computers References: <408e589b$0$28898$61fed72c@news.rcn.com> <7d4190pt88993brl7sqppff1g8ugafqjk2@4ax.com> <42e2905tu557hrutebi91el0s8rr1pujvc@4ax.com> <4092685f$0$28932$61fed72c@news.rcn.com> <40979035$0$3029$61fed72c@news.rcn.com> Subject: Re: were dumb terminals actually so dumb??? Date: Tue, 4 May 2004 17:38:10 -0400 X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 6.00.2800.1409 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1409 Message-ID: Lines: 51 X-Trace: sv3-Jgafd7gDXwOY646QK6BFitzanU3LHd0BiyXOBfKqD9Qz76uMinpO8W8/W8j04KUi5r4i91T+5HnHwz+!dPfk/NYVph6j5HO54F25E9Ogmhp7FZi3VTvlWp3sqjT3pDMUTmN7uSSD1qE= X-Complaints-To: abuse@giganews.com X-DMCA-Notifications: http://www.giganews.com/info/dmca.html X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.1 Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!irazu.switch.ch!switch.ch!news.maxwell.syr.edu!newshosting.com!nx02.iad01.newshosting.com!news-feed01.roc.ny.frontiernet.net!nntp.frontiernet.net!nntp.giganews.com.MISMATCH!border1.nntp.ash.giganews.com!nntp.giganews.com!local1.nntp.ash.giganews.com!news.giganews.com.POSTED!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173447 "Pete Fenelon" wrote in message news:nev87c.2pr.ln@fenelon.com... > I've always preferred > > void cant_happen (const char *f, int l) > { > /* do whatever you need to lock out interrupts! - eg asm("di"); */ > /* do whatever logging needs to be done... eg printf() */ > /* place a breakpoint here on an embedded system */ > for(;;); > > } In an embedded system, sure. Though I'd be more likely to use a HALT (or the selecte machine equivalent in the for loop). > "Can't happens" are then put in as > > cant_happen(__FILE, __LINE__); I never liked using __LINE__. It required that I find the exact same version of the source file in order for the line number to resolve correctly. If I used cant_happen(23), then when I got a "Can't happen #23, just happened" I could open any version of the source and seach for the function and the argument and find it. I've usually avoided __FILE__, but that's for historcal reasons (problems with a few early compilers. Actually, I simplified my example. If I had control of the project the error, number was coded. That is, 1000's would be one file, 1100's would be another and so forth, so I could just GREP the directory or directory tree and it would give me the file and line in one shot. I'd also, if possible, put a one-liner after the function call so the grep would be informative, like this: cant_happen(1123); /* impossible bounded alpha voltage index */ > so I can see where something that couldn't happen happened ;) I can see that working better with some source control systems than with others. > If you're modern you could even make it char *, char *, int, and add > __FUNCTION__, but I'm a luddite ;) :) - Bill ###### X-Trace-PostClient-IP: 68.147.131.211 From: Brian Inglis Newsgroups: alt.folklore.computers Subject: Re: were dumb terminals actually so dumb??? Organization: Systematic Software Reply-To: Brian.Inglis@SystematicSw.ab.ca Message-ID: References: <409269a6$0$28932$61fed72c@news.rcn.com> <1288.616T203T9523048@kltpzyxm.invalid> <87fzajmora.fsf@killer.ninja.frodoid.org> X-Newsreader: Forte Agent 1.93/32.576 English (American) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Lines: 33 Date: Tue, 04 May 2004 21:43:30 GMT NNTP-Posting-Host: 24.71.223.147 X-Complaints-To: abuse@shaw.ca X-Trace: pd7tw2no 1083707010 24.71.223.147 (Tue, 04 May 2004 15:43:30 MDT) NNTP-Posting-Date: Tue, 04 May 2004 15:43:30 MDT Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!switch.ch!news.imp.ch!news.imp.ch!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!newshosting.com!nx02.iad01.newshosting.com!167.206.3.103.MISMATCH!news3.optonline.net!pd7cy1no!shaw.ca!pd7tw2no.POSTED!53ab2750!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173450 On Mon, 03 May 2004 10:58:28 GMT in alt.folklore.computers, Mikko Nahkola wrote: >In article <87fzajmora.fsf@killer.ninja.frodoid.org>, Julien Oster wrote: >> "Charlie Gibbs" writes: > >>> So what would be a good term anyway? If one exists, I can't >>> think of it right now - but we need some unambiguous way to >>> refer to asynchronous character-mode terminals. Hmmm... >>> "character-mode"... maybe that's it. Comments, anyone? > >> No, sounds fine. "block mode" and "character mode" should do it. > >> However, there are also "line mode" terminals... but just using those >> three terms does it and leaves space open for further specification of >> what is meant. > >Indeed, isn't it nowadays common for terminal devices to be able to >switch between line and character mode? Never met a line mode terminal: "line" mode interfaces like X.25 pads, DECservers, and software equivalents were common at one time, where "line" was defined as a bunch of characters ending with a control character, or starting with an escape and ending X ms later; line and character modes are normal for terminal drivers; and line mode is even supported on block mode terminals using older terminal command line interfaces. -- Thanks. Take care, Brian Inglis Calgary, Alberta, Canada Brian.Inglis@CSi.com (Brian dot Inglis at SystematicSw dot ab dot ca) fake address use address above to reply ###### From: Té Rowan Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica Date: Wed, 05 May 2004 01:13:33 +0000 Organization: Word used by Space Aliens Lines: 23 Message-ID: References: <4092463b$1@news.comindico.com.au> <409394F6.4C67558B@optushome.com.au> <4093b2ae@news.comindico.com.au> <4094ed52@news.comindico.com.au> <4094eec4@news.comindico.com.au> <4096B268.7B48@sbseiber.com> <4096BA45.6EAF@sbseiber.com> NNTP-Posting-Host: ppp163-65.as.mi.is Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit X-Trace: news.simnet.is 1083719563 27908 217.151.163.65 (5 May 2004 01:12:43 GMT) X-Complaints-To: usenet-abuse@simnet.is NNTP-Posting-Date: Wed, 5 May 2004 01:12:43 +0000 (UTC) X-Newsreader: Forte Free Agent 1.93/32.576 English (American) Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!irazu.switch.ch!switch.ch!news.maxwell.syr.edu!nntp.abs.net!ash.uu.net!news.simnet.is!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173471 Saith Sam Seiber: >Michael Black wrote: >> And weren't there problems with the clock generator MITS used in the Altair? >> I can picture an article in a very early issue of Byte that addresses some >> problem with the clock generator, though I'm not sure of the problem. >> >> Michael > >Damn I wish I remember. I have an Altair. It isn't working, and I >think >it is a clock problem. The 8080 had a 2 phase clock, and the two phases >had to overlap "just right" for the 8080 to run. My really old brain >can't remember if the voltage of the clock was non-TTL. I have some >memory of 8 volts, but that just could be organic bit rot on my part. I *think* the Intel clock gen's type number is 8224. I wouldn't be too surprised if the 8080 required odd clock voltages. Doesn't it need three rails (+5V, -5V and +12V) anyway? Would be a nice fit with the 4116 DRAMs, then. -- Té Rowan (reynirhs@mi.is) ###### From: et472@FreeNet.Carleton.CA (Michael Black) Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica Date: 5 May 2004 02:59:00 GMT Organization: The National Capital FreeNet Lines: 47 Message-ID: References: <4092463b$1@news.comindico.com.au> <409394F6.4C67558B@optushome.com.au> <4093b2ae@news.comindico.com.au> <4094ed52@news.comindico.com.au> <4094eec4@news.comindico.com.au> <4096B268.7B48@sbseiber.com> <4096BA45.6EAF@sbseiber.com> Reply-To: et472@FreeNet.Carleton.CA (Michael Black) NNTP-Posting-Host: smeagol.ncf.ca X-Trace: freenet9.carleton.ca 1083725940 27479 134.117.136.48 (5 May 2004 02:59:00 GMT) X-Complaints-To: complaints@ncf.ca NNTP-Posting-Date: 5 May 2004 02:59:00 GMT X-Given-Sender: et472@smeagol.ncf.ca (Michael Black) Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!switch.ch!news.ip-plus.net!newsfeed.ip-plus.net!news.tesion.net!news.space.net!newsfeed.freenet.de!newsfeed00.sul.t-online.de!t-online.de!news.glorb.com!news-spur1.glorb.com!news.kjsl.com!xcski.com!freenet-news!FreeNet.Carleton.CA!et472 Xref: redlance.franklin.ch alt.folklore.computers:173473 Té Rowan (reynirhs@mi.is) writes: > Saith Sam Seiber: > >>Michael Black wrote: >>> And weren't there problems with the clock generator MITS used in the Altair? >>> I can picture an article in a very early issue of Byte that addresses some >>> problem with the clock generator, though I'm not sure of the problem. >>> >>> Michael >> >>Damn I wish I remember. I have an Altair. It isn't working, and I >>think >>it is a clock problem. The 8080 had a 2 phase clock, and the two phases >>had to overlap "just right" for the 8080 to run. My really old brain >>can't remember if the voltage of the clock was non-TTL. I have some >>memory of 8 volts, but that just could be organic bit rot on my part. > > I *think* the Intel clock gen's type number is 8224. I wouldn't be too > surprised if the 8080 required odd clock voltages. Doesn't it need > three rails (+5V, -5V and +12V) anyway? Would be a nice fit with the > 4116 DRAMs, then. > It's definitely the 8224. But the question we have is whether the Altair 8800 used it. The 8224 might have not been around when the Altair came out, or maybe too expensive or hard to get, or even possibly that Ed Roberts thought he could do a better job with other components. I thought there was some odd clock circuit in the Altair. I've never seen the schematic, but I'm sure I've seen comments, years ago, to this effect. I did look for what I did remember. I turned out my copy of "The Best of Byte" was a lot handier than I expected. Right there on page 56 is "Assembling an Altair 8800". But I was wrong. This article talks of a problem with the deposit switch. So he added a capacitor in a parallel with the capacitor used for timing in a single shot. I remembered that right, but it has nothing to do with the actual clock for the CPU. There's a photo of a schematic, but it's neither readable nor complete, so while I found the article I was picturing the question of the actual clock still remains. Michael ###### Newsgroups: alt.folklore.computers From: William Robison Subject: Re: Altair 8800 Replica X-Nntp-Posting-Host: polaris.physics.uiowa.edu Content-Type: text/plain; format=flowed; charset=utf-8 Message-ID: User-Agent: Opera7.20/SunOS M2 build 451 Sender: news@sysadm.physics.uiowa.edu (News Administrator) Content-Transfer-Encoding: 8bit Organization: Universitry of Iowa References: <4092463b$1@news.comindico.com.au> <409394F6.4C67558B@optushome.com.au> <4093b2ae@news.comindico.com.au> <4094ed52@news.comindico.com.au> <4094eec4@news.comindico.com.au> <4096B268.7B48@sbseiber.com> <4096BA45.6EAF@sbseiber.com> Mime-Version: 1.0 Date: Wed, 5 May 2004 15:13:08 GMT Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!switch.ch!news.imp.ch!news.imp.ch!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!logbridge.uoregon.edu!news.physics.uiowa.edu!news Lines: 31 Xref: redlance.franklin.ch alt.folklore.computers:173520 On Wed, 05 May 2004 01:13:33 +0000, T� Rowan wrote: > Saith Sam Seiber: > >> Michael Black wrote: >>> And weren't there problems with the clock generator MITS used in the >>> Altair? >>> I can picture an article in a very early issue of Byte that addresses >>> some >>> problem with the clock generator, though I'm not sure of the problem. >>> >>> Michael >> >> Damn I wish I remember. I have an Altair. It isn't working, and I >> think >> it is a clock problem. The 8080 had a 2 phase clock, and the two phases >> had to overlap "just right" for the 8080 to run. My really old brain >> can't remember if the voltage of the clock was non-TTL. I have some >> memory of 8 volts, but that just could be organic bit rot on my part. > > I *think* the Intel clock gen's type number is 8224. I wouldn't be too > surprised if the 8080 required odd clock voltages. Doesn't it need > three rails (+5V, -5V and +12V) anyway? Would be a nice fit with the > 4116 DRAMs, then. > 8224 used an 18Mhz Xtal to make the 2-phase asymetric clock. I think you'll find a 2Mhz Xtal on the Altair CPU. -- -Willy ###### From: dkelvey@hotmail.com (dwight elvey) Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica Date: 5 May 2004 17:18:52 -0700 Organization: http://groups.google.com Lines: 57 Message-ID: <43258753.0405051618.49a9c28e@posting.google.com> References: <4092463b$1@news.comindico.com.au> <4093b4d6@news.comindico.com.au> NNTP-Posting-Host: 139.95.251.9 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit X-Trace: posting.google.com 1083802733 19727 127.0.0.1 (6 May 2004 00:18:53 GMT) X-Complaints-To: groups-abuse@google.com NNTP-Posting-Date: Thu, 6 May 2004 00:18:53 +0000 (UTC) Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!switch.ch!news.imp.ch!news.imp.ch!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!postnews1.google.com!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173571 "Howard Long" wrote in message news:... > "William" wrote in message > news:D9%kc.44042$hR1.3065@fe2.texas.rr.com... > > "Intrinsic" wrote in message > > news:4093b4d6@news.comindico.com.au... > > > > > That's interesting, I always thought that the Z-80 was based on the 8080 > > > basically just a later manufacture by a different company, > > > > It's an "improved" 8080 in that it is very code compatible with the 8080, > > but it's a different chip. Has two sets of registers, for starters (very > > handy > > for interrupts). Interfacing was simplified, IIRC. I programmed the 8080 > > in assembly but by the time I got a Z-80 I'd moved on to C so I don't > > really remember all the code extensions it had. -Wm > > > The Z80 and 8080 are not pin compatible either. The 8080 also needed > additional power supplies (+12V and -5V IIRC) whereas the Z80 managed with > just +5V. The native interrupts operate differently too, although I do not > know how the S-100 bus implemented this: there may have been a similar > > One 'enhancement' was an almost useless dynamic RAM refresh mechanism on the > Z80 - by the time you'd added the glue logic necessary to make it work you > might as well have put your own refresh logic in there from scratch as the > timing never seemed compatible with any dynamic RAM chips you could > purchase. The Sinclair/Timex ZX80 and ZX81 used the Z80's program > addressable refresh counter and vectored interrupt register to provide video > refresh. A real ingenious hack if ever I saw one. Hi I once got some DRAMs from one of the Korean compainies ( I forget which ) that were suppose to be compatable with standard 64Kx1 DRAMs. The problem was these needed a 256 cycle refresh instead of the normal 128 that the Z80 provides. The machine I was using expected this to work. There was a rush on the project and we couldn't wait on more DRAMs so I did a quick hack to the code, such that it only used every other 128 byte page. Luckily, I had enough extra RAM to do this. Dwight > > There was also the addition of the 16 bit IX and IY registers allowing > indirect indexed addressing. This was useful, but back in the days when > programmers cared about how much CPU and clock cycles their programs took > they often found using the standard 8080 16 bit registers more efficient. > > The Z80 has some nice enhancements like the looping DJNZ instruction. Plus > there were the multi-byte instructions, as well as 16 bit addition and > subtraction with carry, many more shift/rotate options, indirect I/O > instructions, bitwise instructions, and short relative jumps. > > IIRC the main (only?) software incompatibility surrounded the way the parity > flag worked: it was used on the Z80 as a way to determine whether the > previous addition or subtraction instruction had overflowed. Otherwise > logical operations affected the parity flag identically. > > Kind Regards, Howard ###### From: Té Rowan Newsgroups: alt.folklore.computers Subject: Re: Altair 8800 Replica Date: Fri, 07 May 2004 17:22:08 +0000 Organization: Word used by Space Aliens Lines: 17 Message-ID: References: <4092463b$1@news.comindico.com.au> <4093b4d6@news.comindico.com.au> <43258753.0405051618.49a9c28e@posting.google.com> NNTP-Posting-Host: ppp162-69.as.mi.is Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit X-Trace: news.simnet.is 1083950487 22357 217.151.162.69 (7 May 2004 17:21:27 GMT) X-Complaints-To: usenet-abuse@simnet.is NNTP-Posting-Date: Fri, 7 May 2004 17:21:27 +0000 (UTC) X-Newsreader: Forte Free Agent 1.93/32.576 English (American) Path: redlance.franklin.ch!pfaff2.ethz.ch!news-zh.switch.ch!irazu.switch.ch!switch.ch!news.maxwell.syr.edu!nntp.abs.net!ash.uu.net!news.simnet.is!not-for-mail Xref: redlance.franklin.ch alt.folklore.computers:173744 Saith dwight elvey: > I once got some DRAMs from one of the Korean compainies ( I forget >which ) that were suppose to be compatable with standard 64Kx1 >DRAMs. The problem was these needed a 256 cycle refresh instead >of the normal 128 that the Z80 provides. The machine I was using >expected this to work. There was a rush on the project and we >couldn't wait on more DRAMs so I did a quick hack to the code, >such that it only used every other 128 byte page. Luckily, I >had enough extra RAM to do this. The Z80 was designed at a time when four rows of 4116s were more memory than you could use in a lifetime -- and more than you could *afford* in a lifetime. -- Té Rowan (reynirhs@mi.is)