Commodore 65 electrical scheme

[Xenobiotical]

Hi Guys,
 
finally i have all components for C65 board. Unfortunately it doesn't power on. Signals (seen with oscilloscope) are all ok... except for CSG 4510.. it seems dead. I think 4510 chip is broken. Let's see. If anyone has spare parts for Commodore 65, please, contact me.
 
Thanks, Carlo

[Xenobiotical]

Board video at this address: http://www.youtube.com/watch?v=Shbp57ePTFU

[Tension]

No news?

[coldfish]

Fascinating project.  I'm not surprised it's hard to find info on the C65, anyone who has one will guard it to protect it's value as a "mythical" object.

I have the poor-mans C65, the C64DTV is a nice advance of the C64 spec.  

[spirantho]

Can you list ALL the socketed chips you have on your board please? That is, with the full markings including revision numbers and everything? Maybe we can spot an incompatilibity...

Have you check the address lines on the CPU with an oscilloscope to see if it's running?

[dabone]

I have a c65 with missing chips also.
Xeno had contacted me and I was going to get it out of storage and maybe sell it off. But after I got it out and had it in my hands again I decided not to.
 
Mine is a full unit missing the bill, u15, and the rom.
 
Gallery of pics is located here.
 
http://img84.imageshack.us/g/dscn0049q.jpg/
 
What's strange is I googled c65 motherboard and came across this photo.
 
http://www.commodore.ca/gallery/hardware/c65.jpg
 
It's from the same batch, and missing the exact same chips. I always assumed the chips were removed because the board was bad, but maybe this batch never got the chips installed?
 
It's keyboard is 87 and mine is 92, made the same day.
 
http://img692.imageshack.us/img692/5794/dscn0056hj.jpg
 
What is the chip at u15 anyway?
 
later,
dabone

[spirantho]

Unfortunately the chances of these boards never being fully populated because they didn't work is rather high - I hope that's not the case here.

I believe U15 is a standard TTL logic chip: a DM74LS125AN in fact - a quad tristate buffer.

It's just possible - but unlikely - that your board would run with the socketed chips Xeno has - what are the revisions on the chips on your board please? Maybe we can get one C65 working...

[danwood]

Hi Guys,
 
finally i have all components for C65 board. Unfortunately it doesn't power on. Signals (seen with oscilloscope) are all ok... except for CSG 4510.. it seems dead. I think 4510 chip is broken. Let's see. If anyone has spare parts for Commodore 65, please, contact me.
 
Thanks, Carlo

If you wanted another power-supply, I remember hearing that the CD32 power supply was the ones originally made for the C65.. infact your photo is identical to my CD32 supply, even down to the sticker underneath which also says "PSU C65".

[Xenobiotical]

Dear Friends,
 
i'm now sure that my only problem in CSG 4510 (Victor CPU). All other components are ok.
 
Take care
 
Carlo

[spirantho]

Remember you need a revision 3 or 4 Victor chip for a rev. 2B board. A 4510R5 (which is what you have on the first page of the thread) will *not* work in a 2B  - the pin-outs are different - you need a 4510R3 or 4510R4.

I feel a bit bad for having to say that - it's like saying to someone "oh, that hen's tooth is no good, it's an incisor and you need a canine" (for the benefit of people outside the UK, "as rare as hen's teeth" means exceedingly hard to find).

Maybe someone out there has a rev. 3 or later board and a rev 3 or 4 4510? That'd be good for both of you!

[dabone]

what are the revisions on the chips on your board please?

 
U3 - 390491-02 71-FDC
U4 & U5 8580R5 Sids
U7 DMagic - 4151R0-018
Victor - (Can't see the socket number) 4510 (no rev, last line is 1690 52)
U11 - Elmer - Hand written label - ELMER1.35A9
Rom is missing.
 
Mine is a rev 2a, so my cpu will not work for you.
 
Later,
dabone

[spirantho]

Actually, it will - if your CPU belongs to your board then it must be an pre-R5, which means it would work.
I suspect you may be getting a mail from Xenobiotical quite soon....

[pwermonger]

If you wanted another power-supply, I remember hearing that the CD32 power supply was the ones originally made for the C65.. infact your photo is identical to my CD32 supply, even down to the sticker underneath which also says "PSU C65".

It also is the same Power Supply that the 1581 3.5" floppy drive used. Possibly also the 1541-II. Seems Commodore was trying to consolodate their power supply types at the time to cut costs so were reusing them where possible on different systems.