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PCM Replacement programming help (LC4128ZE)

bytestorm

bytestorm

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Hey
Since I have a few boards with faulty PCB chips I thought I´d swap them out for the new replacements, but since they are never in stock I might try make them myself.
BOM, gerbers n all are availible at the git but I am not sure how I would go about programming these LC4128ZE .. would a J-link segger be sufficient?

Anyone tried making these or know of a better way to program them? the Jtag points are availible on the pcb..

https://github.com/neogeodev/NeoChips/tree/master/PCM

1669489241221.png
 
Hi bytestorm.
I'm not sure if a J-Link can program these. Granted all the PLD programming cables do basically the same USB-to-GPIO thing but vendors do their best to force users to use their own variant by using special VID : PIDs and commands. Clone Lattice programming cables go for less than $20 on AE, I use one just for convenience.

The software however is a huge pain in the ass. A few years ago Lattice had the great idea to stop the distribution of the package needed for these older parts, so you basically need to find a copy and use it in a not-very-legal way. OpenFpgaLoader might be able to push the bitstream file on its own, I haven't checked.

LC4128ZE's have been unobtainium for the last year but I'm currently awaiting a small shipment of them. Luckily they will be legit and I'll be able to make a few more of these repros soon. They're really the only viable option for 5V logic with such space and cost constraints.
 
furrtek said:
Hi bytestorm.
I'm not sure if a J-Link can program these. Granted all the PLD programming cables do basically the same USB-to-GPIO thing but vendors do their best to force users to use their own variant by using special VID : PIDs and commands. Clone Lattice programming cables go for less than $20 on AE, I use one just for convenience.

The software however is a huge pain in the ass. A few years ago Lattice had the great idea to stop the distribution of the package needed for these older parts, so you basically need to find a copy and use it in a not-very-legal way. OpenFpgaLoader might be able to push the bitstream file on its own, I haven't checked.

LC4128ZE's have been unobtainium for the last year but I'm currently awaiting a small shipment of them. Luckily they will be legit and I'll be able to make a few more of these repros soon. They're really the only viable option for 5V logic with such space and cost constraints.
Click to expand...
There's a version of the software on archive.org, but i don't know if supports the LC4128ZE.
I've seem an EPM7128STC100 been used on a bootleg posted here before, would that work too?

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Yes indeed, an EPM7128S would be up for the job. The pinout is different though, so a different board would need to be designed.
I didn't chose those chips because they aren't made anymore and I didn't want to deal with counterfeits sold as NOS, but it might be worth giving it a shot.

Never seen such a repro used in a bootleg before, very cool find !
Another example showing that bootleggers were ahead of their time regarding preservation. If only they had shared their findings at the time :P
 
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