[Coco] How do I program a new ECB ROM with minimal external hardware ?

[RETRO Innovations]

On 7/29/2024 2:15 PM, coco at jechar.ca wrote:
>
> No I do not need the RPi to program the EEPROM while while the EEPROM
> is installed in the CoCo.
> I do need to be able to read a ROM or EPROM into the RPi's Memory as I
> have a custom EPROM
> I would like to recover. So my idea is to copy the original Tandy ECB
> ROM into the raspberry pi
> and check that I get the same data as the emulator ROM, If I do then
> I will make a copy of the  custom EPROM or to act as the template
> for making another EEPROM or ( 39SF0X0 series FLASH ROM ).
My RPi idea will work fine for this, though you'll need to write a
program on the Pi to read then ROM (and then write the EEPROM).
>
> Given your suggestions do you have any further comments on this plan ?
Sounds like a lot of work to just read 1 ROM.  You sure you don't just
want to send the ROM to someone like myself, and I can read and make you
a new one, for the cost of shipping?  Or, are you going to be at a show
at any time?  I usually bring my programmer to shows, and others do as well.
>
> Charlie

It looks like someone made a RPi config to do this, though they are
letting the data lines come in at 5V into the RPi, and I just verified
the RPi IO is not 5V tolerant.  They must be assuming the data lines are
so small amperage it will not affect the RPi. Anyway:

https://github.com/andrewteall/pi-eeprom-programmer

Here's a few more, (some of which at least use current limiting
resistors on the data inputs)

https://www.instructables.com/Raspberry-Pi-Python-EEPROM-Programmer/

https://zedstarr.com/2021/02/09/reading-a-27c512-eprom-with-a-raspberry-pi-rom-dumping/

https://www.hackster.io/yash-indane/raspberry-pi-eeprom-programmer-cca53b


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