SukkoPera's Open Source Hardware: A500/A600 Chip/Fast RAM Expansions

[SukkoPera]

I have gathered all the information you provided here on this page:

https://github.com/SukkoPera/OpenAmi...ocketRework.md

Feel free to submit any corrections. Thanks a lot!

[katarakt]

Excellent

[SukkoPera]

I have just released the first public version of another project of mine. It is an Arduino-based PlayStation to Amiga/CD32/C64 controller adapter.

It is packed with features, like different button mappings, programmable combos, mouse mode, C64 mode, etc. Please refer to the documentation to find out more.

As usual it's 100% open, both in hardware and software.

ENJOY!

https://github.com/SukkoPera/OpenPSX...eleases/tag/v1

[dalek]

Wow - cool project! Thanks for releasing it as Open Hardware/Software

I'm going to order some boards for myself and give it a go.

[katarakt]

As promised, here are the final information for parts and pics needed for the 100% A600 4MB Fast Ram Expansion:

Nylon Double-pass Pad High Straight Through Column Plastic Washer Round Hole Spacer
M3X7X8mm (8mm = height)

Cross Round Head 304 stainless steel self-tapping with Padded Screws With Collar Pad Washer Silver Fastener Screw
M2.3 x 12 mm

It's fits perfectly (don't forget the socket has to be sanded down!). You don't have to remove the mainboard, just screw it like the ACA620ec. No more worries about fixation

Sukkopera, if you want to add my information and pics to your github...feel free to do so

[voyager_1701e]

Ive got a few of the 4/8MB boards made, stuck the CPLD on and tried to program it with one of the clone USB blasters....as per your suggestion that model hangs at 47% (bugger!!)! Ive ordered the suggested type..awaiting its arrival.

Anyone have a reliable link to a RAM chip that is suitable for the board?

[retrogamer]

Is it possible to buy a prebuild A500 4MB Fast Ram Expansion?

[katarakt]

For the A500/A600 Fastram Expansion you'll find here a memory compatibility list. Btw all SOJ-42 16 Mbit (1M×16) DRAMs should be compatible.

About the altera cplds i've still problems with some to program with my USB blaster. I don't know why, in total i can't program 40% out of 100%.

[SukkoPera]

Yes, I really don't know what's up with that USB Blaster. Mine even programmed like 10 chips, then decided it would ALWAYS get stuck between 47 and 49%. Very weird. Anyway the bigger one works like a charm.

I will add some more chips to the compatibility list as soon as they are tested, but so far we haven't found a single one that is NOT working.

@retrogamer: Not from me at least. Feel free to look around, but please do not buy from anyone who's selling this at more than 30-35€, they are just scammers.

[SukkoPera]

Thought I'd update this thread with my last few releases:

- On New Year's Day I released an Open Hardware clone of the Gotek Floppy Emulator. It has some enhancements over the original one and is fully working. The project page is here.


- Not strictly Amiga-related, but I have redrawn the Commodore 16 schematics in Kicad and published them here. There are some errors I'll fix ASAP, but I think they are much more clearer than what's been around so far.

- I have made a Serial/Parallel Port testing dongle that can be used with Amiga Test Kit and DiagROM. You can find it here.


- Finally I have just released an update of the PlayStation to Amiga/CD32 controller Adapter, whose main news is a much better compatibility with controllers. Now it also works with non-analog ones, which means you can use the Namco Arcade Stick on your Amiga, for instance, and it just feels great. Check it out here.


- The above is possible thanks to an Arduino Library I made, which is much more compatible with controllers than the one I was using before. The library is here. I have also made a shield that allows connecting a PlayStation controller to a plain Arduino and do everything you want with it. Project is here.


I hope you enjoy my work .

[cheshirenoir]

Amazing work there! I especially like your OpenFlops drive emulator.

Looking forward to assembled models filtering into the market.

Again, well done with all of these.

[wiz12]

That Serial/Parallel Port testing dongle looks interesting, will you be selling these on Amibay?

[SukkoPera]

I don't really know. I do these things to learn and to improve the community. I usually sell my excess, but that is not really my focus. For the dongle, in particular, I've kept a couple boards for myself, I sent a few to keirf (author of Amiga Test Kit, also offered a few to Chucky but he never replied) and the rest went to friends of an Italian Amiga forum, so I've already run out of them unfortunately. I know some more people who would like to get one, so I might do another batch in the not-so-close future, but will only offer them as a kit. Anyway anyone can make and sell them, the license allows that, so hopefully someone will help you sooner than that. Or you can just make them yourself .

[SukkoPera]

I have just released OpenVideoModulator, an RGB to Composite/S-Video Converter. It can be useful to get a color signal from your Amiga 500, or Amiga 600 with broken video encoder, for instance. It is based on a circuit used with the Amstrad CPC, so I guess it could be used with other retrocomputers as well.

[JanHolbo]

Originally Posted by SukkoPera

Thought I'd update this thread with my last few releases:

- On New Year's Day I released an Open Hardware clone of the Gotek Floppy Emulator. It has some enhancements over the original one and is fully working. The project page is here.

Does this support the FlashFloppy Second drive option - that is connecting PA3 on the MCU to a second drive select line - pulling it up?

Thank You so much for your hard work for the community!

[SukkoPera]

Yes, that's why the Drive Select jumpers have been turned into a matrix and you can see two jumpers in there. Also the second led has been connected to the second drive select line, that's why the jumper colors match the led colors.

Note that emulating two drives is not yet supported by FlashFloppy though.

[voyager_1701e]

On the 8MB board, can it be assembled with just 4MB?

Id like to try add it to an A500 with an A590, however the 8MB board with no RAM in the A590 doesnt work (just blank screen) - maybe the addressing is conflicting between the 2?

I note the 2MB when populated in the A590 is mapped to $00200020 - $00400000 - so adding the 8MB board exceeds the ZII space (hope I got that right?). If the RAM board is populated with only 4MB would auto-config allocate it a higher address than the A590 RAM?

Anyone more knowledge than me can give me some guidance?

[Daedalus]

Try it with the A590 set to 0MB. There's only 8MB of Z-II space, so if you need more than that for all your devices, some devices won't be initialised. Well-behaved devices should simply be invisible when that occurs, but some devices do not and cause issues when there's not enough space.

[SukkoPera]

The AutoConfig implementation used on the board has some limitations, which I tried to summarize here.

Basically IIRC it will always reply to the first AutoConfig request (which could actually be aimed at another board, there's a signal on the bus to select the target board for every request, but this is not available on the CPU slot and the CPLD pins are all already in use anyway, that's why it can only assume the first request it sees is for itself) and assume it will be granted the RAM slot at the beginning of the ZorroII space ($200000).

What this all means that while the 4 MB configuration is supported, having this board co-exist with another one that used AutoConfig is actually unlikely, unless you use the non-AutoConfig firmware as detailed in the first link I posted.

I was expecting someone from the community would fork this board and fix these issues (I'm not proficient enough in HDLs), but it never happened. Everybody was just quick to take it and sell with a huge markup, even well-respected personalities of the scene. There's very little open hardware culture in the Amiga community, I'm afraid.

At least, Matt Harlum has recently come up with his own interpretation of another board from mkl, which is open. I haven't tried it personally but I'm sure it works great, you might want to try that one.

[voyager_1701e]

Originally Posted by Daedalus

Try it with the A590 set to 0MB. There's only 8MB of Z-II space, so if you need more than that for all your devices, some devices won't be initialised. Well-behaved devices should simply be invisible when that occurs, but some devices do not and cause issues when there's not enough space.

Thanks for the reply. When I initially installed both, the A590 had no RAM onboard, and the A500 didnt start - just a blank screen. The jumper was set to amnesia. Ive since updated the ROM's to v7, i doubt itll make a difference but Ill give it a try.

Originally Posted by SukkoPera

The AutoConfig implementation used on the board has some limitations, which I tried to summarize here.

Basically IIRC it will always reply to the first AutoConfig request (which could actually be aimed at another board, there's a signal on the bus to select the target board for every request, but this is not available on the CPU slot and the CPLD pins are all already in use anyway, that's why it can only assume the first request it sees is for itself) and assume it will be granted the RAM slot at the beginning of the ZorroII space ($200000).

What this all means that while the 4 MB configuration is supported, having this board co-exist with another one that used AutoConfig is actually unlikely, unless you use the non-AutoConfig firmware as detailed in the first link I posted.

I was expecting someone from the community would fork this board and fix these issues (I'm not proficient enough in HDLs), but it never happened. Everybody was just quick to take it and sell with a huge markup, even well-respected personalities of the scene. There's very little open hardware culture in the Amiga community, I'm afraid.

At least, Matt Harlum has recently come up with his own interpretation of another board from mkl, which is open. I haven't tried it personally but I'm sure it works great, you might want to try that one.

Your details make sense to my limited understanding.

I'm thinking a 4MB board with non-autoconfig firmware may work, so the memory can be allocated above the A590. I've consulted your github page and done a bit of googling, but come up blank on the 4MB firmware without autoconfig. Software/firmware writing is well above my paygrade

I looked at Matt's board. Soldering at that tiny level scares my old eyes now hahaha I may visit that one in the future, as I can be stubborn about trying things I may not be able to do but want!

I haven't been keeping up with your posts of late, I knew you were a bit disheartened by some in the community attitude and stealing/selling designs (I saw a seller selling your RAM board a bit above the odds)....but I am grateful for your contributions