crock
Experienced Member
B-series keyboards crop up from time to time on evilbay, especially in Germany. I picked up a nice condition working one last year for around €15-20.
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Commodore B Series?
- Thread starter Pet Rescue
- Start date
B-series keyboards crop up from time to time on evilbay, especially in Germany. I picked up a nice condition working one last year for around €15-20.
billdeg
Technician
You certainly would know, I got my info from Bruce Fierson before he died, he may have just been voicing his opinion.
carlsson
Veteran Member
Although it is not an option for someone just missing a few keycaps, I wonder if the next stage in the "C64 keyboard on PET" project will be to interface a C64 keyboard to the B-series too, or perhaps the matrix/connector is even more different than those on PET motherboards? I never really looked into it.
sjgray
Experienced Member
Certainly power is a concern, but i think you will find enough 128k machines upgraded to 256k to show Its not much of an issue. Its interesting to read through old CBUG articles for little tidbits of info. In general i'd say the whole cbm-ii line is a victim of bad timing... With the c64 being so popular commodore had to allocate most of their resources towards it. Both ram and sid chips. Then there was IBM machines.
With the c64 selling so well there was little need for the P500. The problem was commodore spent a lot of money developing the machines so they didnt want to waste it. They cancelled the P series and reworked the hp motherboards to fiit in those cases. Later they also put the original pet motherboards into the hp cases.
I know one collector who claims to have a 256K P-series machine, but he didnt say if it was factory or upgraded. If you look at the kernal sourcecode on cbug67 you will see compile options for a 256k P system, so its possible.
Unfortunately, the cbm-ii keyboards use a 6 x 16 matrix, which could make adapting the c64 keyboard difficult.
Steve
billdeg
Technician
Steve,
Thanks for the info. I went through my B disks and uploaded them as .D80's so I did not have the threat of being responsible for losing them to "posterity" on my head. Took a while but it was worth doing. Next I'd like to try to work with Anderson Engineering B-1024 upgrade kit, ever heard of that? A 1Mb B Series.
Thanks for the info. I went through my B disks and uploaded them as .D80's so I did not have the threat of being responsible for losing them to "posterity" on my head. Took a while but it was worth doing. Next I'd like to try to work with Anderson Engineering B-1024 upgrade kit, ever heard of that? A 1Mb B Series.
sjgray
Experienced Member
Yes, it's great to get whatever you can archived. I've been meaning to do the same for years but never seem to get the time.
I am familiar with the 1MB board. I have it listed, with picture on my page. You might consider burning and installing my "Fast Boot Kernal" if you get your board installed. It will cut down boot time considerably ;-) I like the board's option of adding ram to bank 15 too.
I understand Michau from cbm-hackers is working on a 1MB memory board as well. With modern chips it can be done with much fewer parts, taking a lot less power.
Do you have a "ColorBOX"? I recently read about it in a CBUG newsletter and was interested in getting a picture and seeing what's inside.
Steve
billdeg
Technician
I can't re-join cbm-hackers for some reason, and I stopped getting emails from it. I just tried the other day to talk about the 1Mb board, and what I have available. I have a few PCB's and I have the hand-written schematics from Mr. Anderson (of the 1024 board). He sent them to me after speaking with me on the phone about it. Steve I am sorry I did not realize you knew so much about the B Series. I kind of live in a B Series island over here.
I don't have a ColorBox but imagine what a 256K B or 1024 B could do with a a VIC II (or colorbox) and a SID chip.
I don't have a ColorBox but imagine what a 256K B or 1024 B could do with a a VIC II (or colorbox) and a SID chip.
sjgray
Experienced Member
I'd love to see those schematics or anything else you might have. If you can spare a board that would be awesome as well ;-) I'm always looking to expand my collection and web page!
Funny, i was talking to a friend of mine just the other day about converting a b machine to a p. Apparently commodore had a machine with both crtc and vic, called the "D128". When the cbm-ii's were cancelled it morphed into the C128.
Steve
Pet Rescue
Experienced Member
Anders
No worries I thought it was worth a check with you after you sorted me with the IEEE-488 cable.
Crock
I'll keep a lookout on Ebay.de thanks for the heads up Rob!
billdeg
I'm feeling paranoid now when I turn it on:D
sjgray
I have a 8250lp up the loft I'll have to get it down to try it!
No worries I thought it was worth a check with you after you sorted me with the IEEE-488 cable.
Crock
I'll keep a lookout on Ebay.de thanks for the heads up Rob!
billdeg
I'm feeling paranoid now when I turn it on:D
sjgray
I have a 8250lp up the loft I'll have to get it down to try it!
billdeg
Technician
One of the .D80's I uploaded has a C-128 CP/M emulator, if you were using the 8088 co-processor (?). Make your CBM 128-80 look like a C-128 running CP/M
I plan to *try* to complete a 1024 board before VCF MW next fall. I will send you a spare board after I have looked it over.
sjgray
Experienced Member
That would be fantastic, thanks! I have two 8088 boards. One I got from ebay (Bruce's son I think) and the other from someone on cbm-hackers. The first one didn't work, and I haven't had the time to test the second. I have copies of the MS-DOS and CP/M disks (probably the same one you saw). I hope to test and/or fix my boards. I'm currently trying to build a CBMX/BX machine with 256K, 8088 board, and 8250LP internal drive. You can see this on my Project page: http://www.6502.org/users/sjgray/projects/bx720d/index.html
Steve
billdeg
Technician
I have about 5+ different versions of CP/M 86 many of these work, you usually need two disks to boot, and they must be in the correct drive. The IBM DOS 1.25 I have works half of the time. I am unsure if my .D80 images work, but if you have a chance and want to test your 8088 card please download my cp/m 86 images to see if you can boot your 8088 system with one of the sets. I labeled the images so that you'd know what disk should be in what drive. I wonder if the 8088 cards are ok, but not all of the software. I used to bang my head against the wall trying to get it to work, but once I found good disks I never had a problem (except for the MS DOS 1.25, fails a lot)
Bill
Bill
sjgray
Experienced Member
Bill, can't see those images. can you tell me where they are?
Steve
Steve
billdeg
Technician
carlsson
Veteran Member
Isn't the "jury still out" on the relationship between D128 and its predecessor P128/B128 and sucessor C128? At least according to what Cameron collected at SWoC, there would not be a definitive line of origin through those models, but barely even the C= engineers at that time (including Bil, who contributes to the cbm-hackers mailing list) could be absolutely sure these days.
sjgray
Experienced Member
According to the book "Commodore: A company on the Edge", page 476... "They were calling it the D128, but it was really a spinoff of the P128"... "It didn't have any C64 compatibility". Then later... "The D128 was a version without the [VIC-II] chip in it". Like the P & B series, it contained a 6509 and a SID chip.
Steve
Pet Rescue
Experienced Member
Back again folks!
I've had a bit of success with the old girl but a bit of failure too!
The good news is that I was able to replace the broken keyboard plungers with Vic 20 ones.
That repaired the "=" key and used the Vic 20 "inst/del" key as a donor "run/stop" key.
The downside was after leaving it on it blew the main fuse rated 1400mA.
I replaced it only for it to blow again.
I removed the funk wotsit line filter and hey presto boot screen!
Does anyone know the correct rated fuse?
I am also getting poor results trying to get the SID sounding right.
I am trying C64 programs but using b series poke's (55808 etc.)
I've had a bit of success with the old girl but a bit of failure too!
The good news is that I was able to replace the broken keyboard plungers with Vic 20 ones.
That repaired the "=" key and used the Vic 20 "inst/del" key as a donor "run/stop" key.
The downside was after leaving it on it blew the main fuse rated 1400mA.
I replaced it only for it to blow again.
I removed the funk wotsit line filter and hey presto boot screen!
Does anyone know the correct rated fuse?
I am also getting poor results trying to get the SID sounding right.
I am trying C64 programs but using b series poke's (55808 etc.)
Last edited:
carlsson
Veteran Member
The fuse was rated 1.4A?!
I can't say for sure about the B500, but I checked my 610 next to me and it is rated to 400 mA, slow blow. It is also what currently is installed.
I can't say for sure about the B500, but I checked my 610 next to me and it is rated to 400 mA, slow blow. It is also what currently is installed.
Pet Rescue
Experienced Member
Cheers Anders upon closer inspection it looks like a t400mA and not a 1400mA!
carlsson
Veteran Member
Nice. I suppose the power supplies are pretty much the same except for in which position they are mounted.
When it comes to the SID, the clock is 2 MHz so you need to use different frequencies than you'd use on a C64. I think it was Bill Degnan who pointed it out to me before. Thus you might want to come up with a formula to calculate the values based on an input clock frequency. I have such formulas somewhere or they could be looked up on the Internet, just that I don't have them available right now though.
When it comes to the SID, the clock is 2 MHz so you need to use different frequencies than you'd use on a C64. I think it was Bill Degnan who pointed it out to me before. Thus you might want to come up with a formula to calculate the values based on an input clock frequency. I have such formulas somewhere or they could be looked up on the Internet, just that I don't have them available right now though.