27C400/27C800 EPROM emulator

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arkadiusz.makarenko
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Re: 27C400/27C800 EPROM emulator

Post by arkadiusz.makarenko » Wed Dec 11, 2019 8:00 pm

cmorley wrote:
Wed Dec 11, 2019 6:55 pm
I am working on tidying up the firmware on this project. FLASH space is a bit tight on the MCU so I put a string table inside the CPLD 8-)

This means that if I shove 90%+ of the strings into the string table then the UI could be translated... is there any point? Just because you can do something doesn't mean you should!

What do people who's first language is not English think?
Are you thinking about Mandarin? ;) If no then English will be ok for 99% of people using this kind of stuff.
It is nice touch, but nothing except that.
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Squirrel61
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Re: 27C400/27C800 EPROM emulator

Post by Squirrel61 » Wed Dec 18, 2019 9:03 pm

This is really sexy!

The short version: I want one, please sign me up.

I can also help with testing/debugging on A500 and A1200 (very interested in the single emulator board for both ROMs!) but I think you already got that covered very well.

cmorley
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Re: 27C400/27C800 EPROM emulator

Post by cmorley » Sun Dec 22, 2019 6:59 pm

I have put in some work on the firmware and it is looking good. You can now program, verify and CRC32. I added dumping contents as Intel HEX, copying between ROM slots as well as a host of behind the scenes menu changes. To save code space most of the strings have ended up in the CPLD FLASH so translating isn't out of the question but as arkadiusz.makarenko posted there is probably little point.

I still have the spare GPIO pin code to write (LED flasher or system RESET control). I also want to see if I can squeeze in an Intel HEX parser for programming but as I have under 1000 bytes left of code space that might not happen!

Squirrel61
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Re: 27C400/27C800 EPROM emulator

Post by Squirrel61 » Wed Dec 25, 2019 1:05 pm

Thanks for the update! It’s looking better and better!

cmorley
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Re: 27C400/27C800 EPROM emulator

Post by cmorley » Fri Jan 03, 2020 7:57 pm

I have been adding more features.

The advanced programming menu is in now and works which allows partial programming and erasing. This is useful for systems like the Acorn Master which have 1 large multi ROM so you can swap a 16KB chunk without resorting to hex edit programs.

I've added the spare pin GPIO to run a power/status LED - C64 power LED could be connected to this. The spare GPIO can also be used to pull the system into reset via serial command.

This is also a feature now on the ROM switch input - on A500 Gary's ~RESET output seems to be open collector so this is safe & I can reset the Amiga from the terminal. Should be useful for chucky developing diagrom or anyone working on OS. Build on PC, put machine in reset, push new code, restart machine - all scripted 8)

I squashed a few bugs too. I have ~800 bytes left so will see if I can fit in an intel HEX file parser for programming - not that I expect anyone will use it... but since I added dump as intel HEX it would be nice to be able to do the round trip!

cmorley
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Re: 27C400/27C800 EPROM emulator

Post by cmorley » Sun Jan 05, 2020 5:52 pm

Intel HEX file parser fit. It is noddy but handles sparse files or files too short for the ROM slot (pads with 0xff).

That's it for features I think now... I need to do a tidy up pass over the code & time for public testing I think :?

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PaulJ
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Re: 27C400/27C800 EPROM emulator

Post by PaulJ » Sun Jan 05, 2020 8:17 pm

@cmorley , out of curiosity why did you choose intel HEX format over Motorola S-Records? I've never dealt with a motorola based product that uses intel HEX. :D

cmorley
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Re: 27C400/27C800 EPROM emulator

Post by cmorley » Sun Jan 05, 2020 10:16 pm

Intel HEX is common, simple and supported by my tools. I never even thought about Motorola s-records. My minipro and Wellon EPROM programmers both support binary and intel HEX... so I chose intel HEX to serialise the ROM dump then added the parser to make the round trip possible :)

srec_cat can convert between the two.

Most people will use BIN I'd have thought.

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PaulJ
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Re: 27C400/27C800 EPROM emulator

Post by PaulJ » Sun Jan 05, 2020 10:56 pm

Ya, most people use binary these days. A lot younger people don't even know what S-Record, Intel formats are.

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Re: 27C400/27C800 EPROM emulator

Post by terriblefire » Sun Jan 05, 2020 11:07 pm

NIce work. If you do a run of these i'd like one or five :)
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