carlsson Posted January 31, 2014 Share Posted January 31, 2014 When it comes to the Z80 and the CP/M mode, supposedly that was an afterthought due to a salesman (?!) at an early stage had promised CP/M support through the C64 CP/M cartridge but it turned out that one would not work with the C128 so they reworked the design and added a Z80 onboard. I may misremember it partly wrong, but it seems that Commodore never intended to make a major entry into the somewhat dwindling CP/M market, even by 1984's standards. I don't know how much more difficult and expensive it would have been to plop in a 8088, and some low end PC compatibles only had 128K anyway so it might have worked. I can't recall when the first Commodore PC (was it the Colt?) was released, but obviously PC compatibles played in a different market and price range than even the C128 could be sold for. It might have been interesting though, probably at the expense of a native 128K 6502 mode. Quote Link to comment https://forums.atariage.com/topic/221357-questions-and-impressions-commodore-128d/page/2/#findComment-2917790 Share on other sites More sharing options...
TMR Posted January 31, 2014 Share Posted January 31, 2014 I have a 128, but it isn't compatible with all c64 games in c64 mode. The issue with the C128 not running a small percentage of C64 software is down to the programs in question overwriting a register that's unassigned on the C64 but in use for the C128 and off the top of my head i can only remember Hawkeye, Dalek Attack and 1001 Crew's ESCOS as falling over. The most common mistake is a programmer dumping to the video registers from a block of RAM and writing a non-zero value to $d030 on the way past; fixing this issue isn't particularly tricky so in the cases were an original game won't work it's worth giving the cracks a try. Quote Link to comment https://forums.atariage.com/topic/221357-questions-and-impressions-commodore-128d/page/2/#findComment-2917826 Share on other sites More sharing options...
JamesD Posted January 31, 2014 Share Posted January 31, 2014 (edited) The C128D is a decent little machine if you want a C128 with an internal drive. It's certainly nice to be able to sit a monitor on it, but even though it was styled after the Amiga 1000 you can't slide the keyboard under it. It's also fairly large and heavy (at least the US model).It's bigger than it needs to be just to sit the monitor on and since the US model has a steel case it weighs quite a bit.One other annoying thing is reaching around back to insert a cart game.Really, these things are pretty minor but there is no significant reason to buy a C128D over a C128. Edited January 31, 2014 by JamesD Quote Link to comment https://forums.atariage.com/topic/221357-questions-and-impressions-commodore-128d/page/2/#findComment-2917830 Share on other sites More sharing options...
Rybags Posted January 31, 2014 Share Posted January 31, 2014 I'd rank compatability with C64 sw as a big non-issue. Supposedly another minor one is that the Caps Lock key also has an input on the 8510 IO port on the 128 and can confuse some C64 software, fix is to just press the Caps Lock key so the normal value is returned there. Compared to e.g. Atari 800 vs XL where at time of release it was probably around 1 in 15-20 titles with problems it's miniscule. Quote Link to comment https://forums.atariage.com/topic/221357-questions-and-impressions-commodore-128d/page/2/#findComment-2917853 Share on other sites More sharing options...
SoulBlazer Posted February 1, 2014 Author Share Posted February 1, 2014 Thanks for all the thoughts and information, guys. Yeah, it seems my memory is a bit rusty, but in 1985 I was only 9. It really was a great system, my 128D....yes, it was kind of large, but nice to put the monitor on top and we'd put other things there also. That thing ran for 9 years without any problems. And wow, someone else remembers Loadstar! I have the full collection on CD that they put out several back, and use it on a emulator these days. The Commdoore could really do a lot of amazing things if programed well. Quote Link to comment https://forums.atariage.com/topic/221357-questions-and-impressions-commodore-128d/page/2/#findComment-2918416 Share on other sites More sharing options...
RobertB Posted February 2, 2014 Share Posted February 2, 2014 Carlsson wrote: > When it comes to the Z80 and the CP/M mode, supposedly that was an afterthought due to a > salesman (?!) at an early stage had promised CP/M support through the C64 CP/M cartridge but it > turned out that one would not work with the C128 so they reworked the design and added a Z80 > onboard. I may misremember it partly wrong, but it seems that Commodore never intended to make a > major entry into the somewhat dwindling CP/M market... Hmm, I'll double-check that against Brian Bagnall's book, Commodore: A Company on the Edge. > ...even by 1984's standards. I don't know how much more difficult and expensive it would have been > to plop in a 8088... Heh, CBM had no MOS 8088s. > ...I can't recall when the first Commodore PC (was it the Colt?) was released... Yes, it was the Colt. > It might have been interesting though, probably at the expense of a native 128K 6502 mode. Interesting but CBM engineer Bil Herd wanted as much compatibility as possible. Truly, Robert Bernardo Fresno Commodore User Group http://videocam.net.au/fcug Quote Link to comment https://forums.atariage.com/topic/221357-questions-and-impressions-commodore-128d/page/2/#findComment-2919145 Share on other sites More sharing options...
RobertB Posted February 2, 2014 Share Posted February 2, 2014 JamesD wrote: > It's also fairly large and heavy (at least the US model). Hmm, I'll have to weigh my European plastic C128D and my metal North American C128DCR. > Really, these things are pretty minor but there is no significant reason to buy a C128D over a C128. I like the C128DCR minor things, like everything being in one box, more video RAM, and the upgrade ROMs for the computer and drive. (Well, the upgrade ROM for the drive was significant. To this day, I have to explain to flat C128-1571 newbies why their 1571s have so much difficulty switching between C64 and C128 mode, why their directories are corrupted, etc.) The old 1571 ROM was troublesome, Robert Bernardo Fresno Commodore User Group http://videocam.net.au/fcug Quote Link to comment https://forums.atariage.com/topic/221357-questions-and-impressions-commodore-128d/page/2/#findComment-2919149 Share on other sites More sharing options...
RobertB Posted February 2, 2014 Share Posted February 2, 2014 Soulblazer wrote: > And wow, someone else remembers Loadstar! I have the full collection on CD that they put out... Did you know that while the Loadstar CD has the first 200 issues (not including the Loadstar 128 issues and special collections), Loadstar continued to issue 250? Those last issues should be put on CD, Robert Bernardo Fresno Commodore User Group http://videocam.net.au/fcug Quote Link to comment https://forums.atariage.com/topic/221357-questions-and-impressions-commodore-128d/page/2/#findComment-2919155 Share on other sites More sharing options...
RobertB Posted February 2, 2014 Share Posted February 2, 2014 I wrote: > ...I'll double-check that against Brian Bagnall's book... I didn't even have to dig out my copy of the book. Here is what CBM engineer Dave Haynie said in another forum -- December 10, 2013 at 3:00 pm Once again, the whole point of the Z-80 was to enable, cheaply, access to lots of existing software that could take advantage of the 80 column display. That was it — the Z-80 was because of CP/M… all kinds of business software available off-the-shelf. Truly, Robert Bernardo Fresno Commodore User Group http://videocam.net.au/fcug Quote Link to comment https://forums.atariage.com/topic/221357-questions-and-impressions-commodore-128d/page/2/#findComment-2919194 Share on other sites More sharing options...
carlsson Posted February 2, 2014 Share Posted February 2, 2014 Hm, ok. So Z80 and CP/M were part of the original spec, assuming that the cartridge would have been usable before taking the decision to integrate a Z80. It reminds me that even some C64 boxes may have a blurb about being CP/M compatible through additional expansion. As for where to source chips, did MOS produce their own Z80 or were Zilog easier to deal with than e.g. Intel? There is a chronology that says the first Commodore PC was launched at the Hannover Fair in April 1984, that Bil Herd became the lead designer of the C128 in September 1984, and the Z80 was incorporated to its motherboard in December. Quote Link to comment https://forums.atariage.com/topic/221357-questions-and-impressions-commodore-128d/page/2/#findComment-2919417 Share on other sites More sharing options...
SoulBlazer Posted February 2, 2014 Author Share Posted February 2, 2014 Soulblazer wrote: > And wow, someone else remembers Loadstar! I have the full collection on CD that they put out... Did you know that while the Loadstar CD has the first 200 issues (not including the Loadstar 128 issues and special collections), Loadstar continued to issue 250? Those last issues should be put on CD, Robert Bernardo Fresno Commodore User Group http://videocam.net.au/fcug Yes, I did know that. I was in touch with the 'new' editor for Loadstar for a while after Fender Tucker gave it up -- can't recall his name right now, but we talked for a while when he was doing those last issues. Very nice guy. I helped him also get LS working on emulators and all that. I'll have to see if I can obtain the ROM images for those last 50 issues. To think that it had the run that it did is amazing and proof of how strong and viable the Commodore community is. (Hell, I got some letters published in LS BITD and also did a contest where I got some free issues.) Quote Link to comment https://forums.atariage.com/topic/221357-questions-and-impressions-commodore-128d/page/2/#findComment-2919425 Share on other sites More sharing options...
RobertB Posted February 4, 2014 Share Posted February 4, 2014 SoulBlazer wrote: > I was in touch with the 'new' editor for Loadstar for a while after Fender Tucker gave it up -- can't recall his name right now... Dave Moorman > To think that it had the run that it did is amazing and proof of how strong and viable the Commodore community is. Well, there wasn't enough enthusiasm to keep it going past issue 250. >( Hell, I got some letters published in LS BITD and also did a contest where I got some free issues.) I had an article or two published in Loadstar Letter and was the story writer for the Loadstar-published multi-color graphics slideshow, "Murder by Commodore," in issue 214. Truly, Robert Bernardo Fresno Commodore User Group http://videocam.net.au/fcug Quote Link to comment https://forums.atariage.com/topic/221357-questions-and-impressions-commodore-128d/page/2/#findComment-2920590 Share on other sites More sharing options...
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