Petsd

[ngtwolf]

I'm trying to build out the PET SD. One thing though, the Attiny chip doesn't appear to have the hex file up on their site that I can find, they only have the compiled files for the Atmega chip. They do have the source for the Attiny chip but I don't really have an easy way to compile that. Does anyone maybe have the hex file for the attiny45/85 chip or maybe can read in the one from their petsd?

Thanks!

[alank2]

The source contains the project :

lcd-i2c-pwm-io

I²C-LCD-PWM-I/O
===============


The petSD+ rev. 2.x boards come with a further Atmel ATtiny slave MCU to support the main MCU.
It serves three purposes:

- output a PWM signal to adjust the LCD contrast
- output a PWM signal to adjust the background display's brightness
- output a digital signal to switch between IEEE-488 and IEC bus

I can probably compile this for you later tonight with Atmel Studio 7, but there are no guarantees it will be the same binary that it is usually compiled to. It looks quite simple though so I'm sure it would work.

[ngtwolf]

I can probably compile this for you later tonight with Atmel Studio 7, but there are no guarantees it will be the same binary that it is usually compiled to. It looks quite simple though so I'm sure it would work.

Yeah, that was the problem I had (I think i mentioned in my post), that the site only includes the source and I have no easy way to compile it (and don't really want to set up a compile environment for one attiny chip ). But, if someone had a PetSD and a Minipro they could read the chip and save the hex file, or maybe they already had it? It's funny they have the binaries compiled for the main chip but not the LCD attiny.

[alank2]

If you don't get anyone to provide a HEX they read from it let me know and I'll compile you one. It will probably work fine.

[alank2]

Enclosing the compiled project. When you flash it to the tiny25 make sure you also set the fuses correctly according to the original makefile:

# AVR fuses settings
LFUSE = e2
HFUSE = d4
EFUSE = ff

There is a HEX and ELF file in the release directory:

lcd-i2c-pwm-io.zip

[ngtwolf]

Great, thanks! I'm having some other problems with my build that I need to figure out (not recognizing my sd card for some reason), so once I'm sure everything is working and that I flashed this correctly I'll update this thread.

Thanks again!

[dabone]

Want to share your shopping list? That's one of the things keeping me from trying one of these.

If you have a mouser or digikey part list, that would rock.

[ngtwolf]

Want to share your shopping list? That's one of the things keeping me from trying one of these.

If you have a mouser or digikey part list, that would rock.

Most of my ordering was parts I either had and the stuff I didn't have, i ordered from aliexpress because I wasn't in a rush for any of the parts. I don't really have a 'parts list' per se, other than whats on the petsd.net site:

http://petsd.net/psdp24-BOM.txt

Basically just had the board made via pcbway, the bought the parts I didn't have. The few more difficult things to get would be:

SD Card: https://www.aliexpress.com/item/33007764892.html
24 pin edge connector (a8 or a9): https://www.aliexpress.com/item/4000600379941.html
rtc: https://www.aliexpress.com/item/32900267627.html
mcp 1702: https://www.aliexpress.com/item/33026766626.html

the edge connector is just the route i chose to go because the IEEE method is a bit overkill and pretty expensive. Also, I had these built with a friend so we went in together on a few things and then split some orders up. I'm going the whole route with lcd and everything, but he was able to build it with a lot less parts as a bare minimum, but he knows better what he's doing than I do. Even then, i'm not really sure theres much savings to be had vs the cost and time to build it. If you do build it, Chuck Hutchens has a video on youtube of building it, so that is helpful as well.

Either way, work has been to busy to diagnose what's up with mine yet, so hopefully i can return to it soon. too many half completed projects..haha.

[jenfosk]

Thank you alank2 for the .zip file for the attiny!

I also had been trying with no luck to find this last few months as I was building my petSD+ v2.4.

I have not yet (if ever) been able to understand using the sourcecode/compiling / makefile stuff.

Someone is currently selling the bare curcuit boards on e-bay
here in the US that matches the petSD+ v2.4 schematic,
and I already had most all of the parts needed, so thought I would give one a try.

The firmware for the attiny was the last piece I needed.
I had figured out that the attiny really does not do much at all,
I really do not want/need the adjustable brightness or contrast,
I assume and a simple switch on the /IEC line can be used to change between IEC/IEEE if needed,
(after also switching it in the menus obviously)

I used the .hex file in the "release" directory of your .zip file ,
wrote it to an attiny(85) with your fuse settings , using a TL-866 mini pro programmer,
and it seems to work fine.
and the petSD+ is not complaining anymore that no PWM controller is present.

Thank you again. ---Kyle

[ngtwolf]

So 6 months later I finally got around to mostly completing this. I dont' know if the Attiny chip works because after a ton of troubleshooting, it turns out that I have the mcu fluke that is described in the url below. So, I can only use up to 10-05-2017 firmware because later firmware won't work. I might try getting another Atmega 1284 chip and hope it likes that one. But yeah, the older firmware doesn't support the clock chip or have a few other nice things like proper brightness on the lcd.

http://www.primrosebank.net/computer..._petsd_fwq.htm

It appears the PetSD is mostly abandoned as well so whatever this weird bug is with some MCU's won't ever get fixed.