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A PET storage option

Hi Mike,

Things to make sure -
- Power connected (USB cable from PETdisk board to cassette board)
- uSD card (FAT32 formatted) in slot
- jumper setting:
no jumper: device 8
jumper on right: device 9
jumper on left: device 10
jumper on both: device 11

double check these, then try a 'load "$", 9' - I believe I preset it to device 9 - and see if you get a directory.
If not, please let me know and we'll figure it out from there.
 
Eudimorphodon said:
If the idea is to remake the board from whole cloth would there be any attraction to the idea of perhaps trying to use a 5v flash memory instead of an EPROM to allow the board to be programed in-situ? (Or, a really wacky idea: Forget having an EPROM at all. Make a board that has 128k or more of SRAM on it and has a small microcontroller and a couple latches that can load your desired firmware into a section of SRAM and write-protect it. The firmware could thus live on a small SPI-connected flash device and selection could be made via a serial line or something.)
Click to expand...

I like the idea of using SRAM with write-protect for the ROM portion, and no EPROMs. Could even use another SD card to keep the ROM images, so you could change them easily. Basically the process at startup would be:
- hold 6502 in reset
- mcu initializes SD card and reads ROM file from the card
- load contents of ROM onto SRAM
- mcu releases address and data lines, releases 6502 reset and computer springs to life.

there would also be some logic to exclude the video RAM and IO portion, so the SRAM doesn't talk when it's not supposed to.
 
Hi again,

I just got back home after several days roaming, and ready to get things squared away as far as the PETdisk is concerned.
The new PETdisk boards have shipped from the manufacturer, but have not arrived yet. They are expected to arrive on monday. I'm still aiming to send those out on Monday, at least the kits and probably 1 of the assembled boards. The remainder of the assembled orders will ship on tuesday or wednesday.

I'm going to put up the much-requested documentation and other technical details this weekend. Link to follow shortly.
Again thanks to the brave early users/testers!
 
More troubleshooting thoughts, Mike -

Just remove all jumpers from the PETdisk board, connect everything, and then try 'LOAD "$",8'..
Also if you can, please try the passthrough part by connecting another drive. Jumper the PETdisk to something other than the drive number of the connected IEEE drive, though.

If that fails I'll walk through other possibilities with you. If all fails I'll ship you a new tested one next week. :)
 
Removing the jumper did the trick, thanks, guys; just assumed the default would be 8 but I guess I shoulda listened ;-). Funny, I did try 9 and 10, but maybe the other drive was connected at the time.

Only had a few minutes to play with it; loading worked fine, but didn't seem to want to save (card is unlocked).

Didn't really complain about coexisting with an 8050 unit 9, or about being shared by an 8032 and a 4032, although there were some glitches; will report when I've had time to investigate further.

Can we set up a wiki or something somewhere where we can all post our various problems and discoveries in one convenient list? Or maybe just report to Gubbish (or?) and he can maintain a list of known issues somewhere?

@Gub: here's the 40 column emulator for the 8032:
View attachment 80240.zip

Also, I've found some cassette port connectors for .75 ea; PM if you're interested.

Question: nothing else is ever going to plug into the USB B jack on the cassette adapter, right? Can I remove the jack and hard-wire a short USB A cable to it?
 
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Sounds good. To figure out what's up with the saving, maybe try this -

reformat sd card with FAT32.
put in petdisk and start up computer.
type in simple basic program,
then 'SAVE "TEST",8'.

should come back to the ready prompt, then try 'LOAD "$",8'. Hopefully the test program will show up there.

Also please make sure to use names of 8 characters or less when saving. If the file system got affected somehow in the first few attempts, this may be causing trouble.
 
gubbish said:
Sounds good. To figure out what's up with the saving, maybe try this -

reformat sd card with FAT32.
put in petdisk and start up computer.
type in simple basic program,
then 'SAVE "TEST",8'.

should come back to the ready prompt, then try 'LOAD "$",8'. Hopefully the test program will show up there.

Also please make sure to use names of 8 characters or less when saving. If the file system got affected somehow in the first few attempts, this may be causing trouble.
Click to expand...
Tried that, nothing got saved; card looks fine on the PC, as though nothing had happened. Might be the other drive interfering, or maybe just a finger malfunction.

One of my uSD cards came with the cutest little USB adapter; how do they make this stuff so small...

uUSB1.JPG
 
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Ok, maybe you can try it again without the other IEEE drive attached, to check if that is indeed the issue. Like the little USB adapter!
 
Yes, I forgot to mention in my review that PETdisk does not seem to like having a powered-off 4040 drive attached. It works fine sharing the IEEE with another device that has a unique address and is powered up.
 
dave_m said:
Yes, I forgot to mention in my review that PETdisk does not seem to like having a powered-off 4040 drive attached. It works fine sharing the IEEE with another device that has a unique address and is powered up.
Click to expand...
Maybe that's just the CBM IEEE implementation; I'll put an unpowered 4040 drive on the bus and see if it bothers the 8050.
 
gubbish said:
Ok, maybe you can try it again without the other IEEE drive attached, to check if that is indeed the issue. Like the little USB adapter!
Click to expand...
Of course you've all seen the regular size convertible SD card with USB built in:
SDSDPH-008G-A11.jpg

Gub, ya didn't answer/comment on my post # 87 re cassette connectors, wiki, USB cable etc.
 
MikeS said:
Can we set up a wiki or something somewhere where we can all post our various problems and discoveries in one convenient list? Or maybe just report to Gubbish (or?) and he can maintain a list of known issues somewhere?
Click to expand...

Good idea - I have a placeholder page for PETdisk information at http://bitfixer.com/PETdisk. Nothing much there yet, I'm planning to have documentation, schematics, etc. here. This might be a good place to have an information repository on issues/discoveries.

@Gub: here's the 40 column emulator for the 8032:
View attachment 6549
Click to expand...
Excellent, I'll check this out.

Also, I've found some cassette port connectors for .75 ea; PM if you're interested.
Click to expand...
I am interested - will send you a PM about this. This would be preferable to cutting the 12-pinners in half.
Question: nothing else is ever going to plug into the USB B jack on the cassette adapter, right? Can I remove the jack and hard-wire a short USB A cable to it?
Click to expand...
Correct, that would be fine. I'm using standard USB pinout. Power, ground - data- carries the cassette read signal, data+ the cassette write.

Dave, thanks for the mention of the powered-off drive issue. I do remember encountering this once when trying with my finicky SFD-1001. I didn't know if it was common to IEEE drives or just mine, which is very flaky at the moment. So perhaps the bus signals are being loaded by the powered-off device. I would try everything again with no drives at all connected to the PETdisk to see if everything works - then with drives connected and turned on.

Thanks again for the reports!
 
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Just letting everyone know that I received the new batch of PETdisk PCBs from the manufacturer, and I put one together. After testing, everything checked out, and thankfully I didn't introduce any glitches into the board with the layout tweaks. So today and tomorrow I will be putting the kits together and building the assembled orders, and will be shipping as soon as they are ready. I'll send a PM to everyone who ordered to confirm the details.
The official website for the petdisk will be at:

http://bitfixer.com/PETdisk

Not much there now but more to come shortly. Thanks for the interest!
 
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Hi all,

PMs have been sent to those who ordered, and orders have been sent to those who replied so far.
I posted assembly instructions for those who ordered the PETdisk in kit form.
Thanks again for the interest, and expect more updates to follow. Still need to write up some formal documentation, as well as posting the full schematic and code for those who would like to build a PETdisk from scratch.
I still have several boards remaining if anyone else wants one.
All details will be up at
http://bitfixer.com/PETdisk.

Thanks!
 
I haven't gone through them in detail step by step, but those instructions look great; nice work all around!

Now where can I find the meanings of the jumper again? ;-)
 
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