In Circuit EPROM emulator and debugger

Using, learning, programming and modding the Gigatron and anything related.
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Posts: 32
Joined: 11 Apr 2019, 07:15
Location: Valladolid, Spain

Re: In Circuit EPROM emulator and debugger

Post by gesari »

First excuse me for my long time out of the forum.
I'm not planning to sell any kit for the ROM emulator, but the layout files are freely available and there are many prototype makers around for the PCB (I ordered the boards to

The components are SMD and they may look difficult to solder, but this is easily done with a fine-point iron solder and a magnifying microscope. The trick for the fine-pitch components is not to apply any solder. Just paint the footprint with a flux pencil, place the component over it, and then apply heat to its pins. There is tin on the pins and the PCB already, and this tin is enough for soldering the pin to the PCB.

The firmware is also freely available.(And surely it can be improved :)

Best Regards
Posts: 19
Joined: 27 Jun 2018, 18:40

Re: In Circuit EPROM emulator and debugger

Post by kerouanton »

Thank you for this nice project. I'm pretty sure your BOM will be shortly part of my next Mouser order!
Posts: 6
Joined: 19 May 2020, 12:50
Location: Canada

Re: In Circuit EPROM emulator and debugger

Post by frob »

This is a fantastic addition for the Gigatron. well done! I am just ordering my Gigatron kit and already was scheming to do something similar.
I'd like to modify your design a little to use a different RAM device: i found a non-volatile SRAM, which once programmed can be used stand-alone like the original EPROM, so it would be detachable from the emulator/debugger board.
I'm curious what CAD software you used, and if you'd be willing to share the source file ?
I do a lot of SMD prototypes and for that i generally like to design and order a small stainless stencil along with my boards, it makes assembly and soldering a lot quicker with less bridging etc. for that to work well its best to tweak the aperture design a little and generate that from the source along with the gerbers.

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