PDA

View Full Version : PET roms



richard at home
June 25th, 2014, 03:08 AM
Any pointers for which ROM's should be in a 3032 PET?

I have some eproms in mine labelled:

UD9: 901465-22
UD8: 901447-29
UD6: 901465-20
UD5: 901465-23

Nothing in UD7, UD4, UD3.

Looking on zimmers:
901465-22 is rom basic 4.0 F000-FFFF.
901447-29 is rom basic 4.0 E000-E7FF.
901465-20 is rom basic 4.0 C000-CFFF.
901465-23 is rom basic 4.0 B000-BFFF.

So presumably I am missing D000-DFFF which go in UD7? Part number:901465-21

dave_m
June 25th, 2014, 07:44 AM
Yes, the -21 is correct.

richard at home
June 25th, 2014, 08:49 AM
Yes, the -21 is correct.


Hi Dave,

Thanks for the response. I'm new to PET's so I've been digging around on the zimmers site.

The 3032 I have has got 2716 (in UD8 ) and 2532 (in UD9,6 and 5) eproms fitted, a mix of Nat Semi and Texas parts. (probably not good?)

I have ordered one of the cheap chinese TOP853 programmers, so I'll see if it will do the business.

(unless someone on here has a spare chip for sale!)


I've seen the adaptors to adapt other eproms.


Cheers,

Richard.

dave_m
June 25th, 2014, 09:18 AM
The 3032 I have has got 2716 (in UD8 ) and 2532 (in UD9,6 and 5) eproms fitted, a mix of Nat Semi and Texas parts. (probably not good?)



You have the right parts. The 2716 is correct for the 2K edit ROM (UD8 ). National Semi was a second source for the TI 2532.

Let us know if you have any problem with the TOP853.

richard at home
July 13th, 2014, 09:57 AM
You have the right parts. The 2716 is correct for the 2K edit ROM (UD8 ). National Semi was a second source for the TI 2532.

Let us know if you have any problem with the TOP853.


Hi David,

I got some eproms and a TOP853.

It doesn't show TMS2532 but it does have TMS2564 which is a 28 pin device.

They are pin compatible but the vpp has to be routed from two pins up on the zif socket to pin 21 on the 2532.

I made an adaptor to do that.

Next I checked the vpp and the TOP853 won't go to 25v despite listing it as an option.

The programmer has a software controlled dc-dc converter and you can see it doesn't even bother to try and get 25v, it just uses the same timing for 21v!

I will see if there is a firmware update that makes vpp go to 25v. Failing that i may have to put an external 25v in somewhere.

It's an odd design as it uses 74hc4094's to drive the different vpp pins so their vcc is at vpp! The 74hc4094's have their gnd pins connected to 1.4v below vpp.

dave_m
July 13th, 2014, 10:37 AM
It's an odd design as it uses 74hc4094's to drive the different vpp pins so their vcc is at vpp! The 74hc4094's have their gnd pins connected to 1.4v below vpp.

Richard, that does seem strange. Keep working on it if you want as you are learning a lot about this stuff, but I can send you a 2532 with the -21 image. Is that the only one you need? Send me a mailing address using private message. I have an ancient Data I/O Model 29B prom programmer that I like to use once in a while.
-Dave

harry
July 13th, 2014, 11:34 AM
Richard , I see Dave has offered to get you sorted, but I just noticed your in Dorset ,not that far away from sunny Somerset, , you are welcome to send me your eprom, or call up and I can burn the rom you need, while you have a cup of tea! could then test all of your roms in my working machine, just let me know if I can be of help!.......
Harry

dave_m
July 13th, 2014, 01:05 PM
Harry,
Yes that would be a lot faster. I ship regular mail and it takes 3 weeks by slow boat.
-Dave

richard at home
July 14th, 2014, 02:50 AM
Richard , I see Dave has offered to get you sorted, but I just noticed your in Dorset ,not that far away from sunny Somerset, , you are welcome to send me your eprom, or call up and I can burn the rom you need, while you have a cup of tea! could then test all of your roms in my working machine, just let me know if I can be of help!.......
Harry
Hi Harry,

Where about's are you?

(I sent you a PM)

richard at home
July 14th, 2014, 03:56 AM
Success!!!!

I patched in a 25v supply for vpp and then did the Bob Roberts 18,20 and 21 pin swap mod socket to make the 2532 compatible with 2732 and my third eprom programmed 100%.

My PET is now 100% working!

Thanks for all the help.

Disk drives to sort out next!

dave_m
July 14th, 2014, 09:10 AM
Richard,
You did super! Another Commodore PET is alive.
-Dave