PET Diagnostics - Upcoming Project Preview (using Atmel)

[ChuckT]

PET Diagnostics - Upcoming Project Preview

Quote:

This is a preview of an upcoming project. Not sure if the name will stick, but at the moment it's called PET Exerciser (UPDATE: it didn't, it's now called 6502 Diagnostics). This started when I was repairing a few PETs and was using a NOP generator. This idea of these is the hard wire the NOP instruction onto the processor databus, the end result of that is it just steps through all the addresses sequentially, continually. That is useful to check address decoding, and see if chip enable pins are pulsing in the right way. The trouble is the 1MHz 6502 based NOP generator is a bit slow to check high address bits on a scope (at least one without digital storage), but too fast to check by eye.

http://blog.tynemouthsoftware.co.uk/201 ... w.html?m=1

http://hackaday.com/2016/07/14/microcon ... -for-cpus/

[BigEd]

Odd that hackaday should run this item - the product was released a couple of weeks ago. See the newer blog post at
http://blog.tynemouthsoftware.co.uk/201 ... stics.html
(Which we posted about on the mos6502 account)

It's a diagnostic module which fits into a 6502 socket, initially configured for fitting into a PET, which tests RAM and ROM and so on, and displays results on the machine's screen - which does mean the screen needs to work. There's a planned later project which would be USB-connectable for diagnostics when then screen isn't working. Most likely the same approach can be used for other systems with a 6502 socket.

[chitselb]

Both this product and the PETvet (found at http://www.bitfixer.com/bf/petvet ) plug into the 6502 socket. They seem to have the same purpose, but what are the similarities and differences?

[BigEd]

Thanks for the pointer - PETvet looks like an interesting and slightly different idea. Do we know if it is still currently available? I see it's an open source design, so presumably one could still make one up.

I see these differences, if I've understood correctly:
- PETvet has a serial connection to dump PET contents to a host, whereas something like that might be a future enhancement to PET Diagnostics.
- PETvet once installed does run as a PET, like Dave's earlier RAM ROM board, whereas PET Diagnostics is purely a diagnostic aid.
- PET Diagnostics has onboard diagnostics such as a memory test.
- PETvet ships from USA, PET Diagnostics from UK.

(But I say all this without having experience of either.)

[chitselb]

I have a PETvet in my 2001-N16 (which I upgraded to 32K and BASIC 4) and it is very nice. It arrived in 2012 a few months after I ordered it. These are hand-built, and I think Mike is otherwise a pretty busy guy when he's not playing hardware factory. I was able to log into the PETvet via terminal and inspect memory, see what's on the screen, etc...

Currently it replaces RAM/ROM but not I/O. I'm wondering if the PETvet (or a similar board) could be used (with a big pile of software on both sides) to remotely control a PET through an on-board Raspberry Pi. The Pi 3 has built-in wifi and bluetooth. What else could
a Raspberry PET(tm) do?

[cbmeeks]

I have a PET 8032 that I would love to do something with. I have so many projects...lol.

Any suggestions? I think the PET needs an awesome sound card! Imagine playing chiptunes with that futuristic PET sitting on your desk.

[barrym95838]

Do you have enough room for one more "project", Mr. Meeks? I finally got a few fires put out over here, and I'm almost ready to send you some "goodies" ... well maybe "not-so-goodies", but you know what I mean.

Mike B.

[chitselb]

cbmeeks wrote:

I have a PET 8032 that I would love to do something with. I have so many projects...lol.

Any suggestions? I think the PET needs an awesome sound card! Imagine playing chiptunes with that futuristic PET sitting on your desk.

I'd really like to see "Raspberry PET" -- a PET add-on with an internally mounted Raspberry Pi 3 providing some subset of these features:

• bluetooth keyboard support
• bluetooth game controller support
• external control via wifi
• mirror PET screen to HDMI
• disk emulation
• tape emulation
• ROM switching/replacement
• RAM replacement
• audio out

[BigEd]

(There would probably be some minimal amount of electronics needed for that project, as the Pi doesn't have 5V tolerant I/Os - a level shifter is needed.)

[barrym95838]

http://schmenk.is-a-geek.com/tarfiles/UserManual.pdf

Mike B.

[BigEd]

Nice one - a Pi for Apple II, using a standard adapter card with an ACIA, and a program on floppy.

As the PET is quite a simple machine (only the CPU is in charge of the bus) it might be possible to use the 28 I/Os on a Pi to control the PET from the 6502 socket. Still there's a need for level shifters. But Telmo Moya's project putting an ARM into a C64 shows what can be done. He even uses a 5V-compatible ARM board.
viewtopic.php?f=4&t=4171

[cbmeeks]

barrym95838 wrote:

Do you have enough room for one more "project", Mr. Meeks? I finally got a few fires put out over here, and I'm almost ready to send you some "goodies" ... well maybe "not-so-goodies", but you know what I mean.

Mike B.

I always have room for more projects. Just like I always have room for more computers. LOL

Seriously, what kind of goodies are you talking about?

**EDIT**

Wait, I think I remember.

[KC9UDX]

cbmeeks wrote:

I have a PET 8032 that I would love to do something with. I have so many projects...lol.

Any suggestions? I think the PET needs an awesome sound card! Imagine playing chiptunes with that futuristic PET sitting on your desk.

Your 8032 should be able to play chiptunes just fine. If not, adding sound is a routine thing to do to a PET: https://www.youtube.com/watch?v=ot_Rp_e_WIY

But other things have been done. https://www.youtube.com/watch?v=1rHIf__9FoQ

[cbmeeks]

Wow. That is awesome. It's amazing what people have figured out to do with their hardware. This reminds me of the videos where people discovered how to play music with the Altair. Also shows you what you can do with a VIA.

[KC9UDX]

Very true. It really is the VIA shift register doing all the work.

Have you seen the demos? One is called No Pets Allowed. https://youtu.be/ktUguF1TnJk