ET-3400 ROM - DRAFT Gerber files, Schematic and Description sheet uploaded.

I created the draft version of the gerber files, the schematic and a description sheet for the board.

Unfortunately, once again, I have to discuss panelisation and v-cuts with JLCPCB before I place an order as I am not sure which option to choose so I get the right outcome. I want to make sure the artificial notch in the PCB is drilled between two boards layed out end to end (see below image). If the boards were in the same orientation, the centre notch is not round any more and is impossible to drill. I eventually got this right on my last order with them but it took days to explain. Hopefully things will go smoother this time.

I also updated the Programming adapter PCB a bit more to clean it up. I'm never 100% satisfied with the PCB artwork and have to keep fiddling with it until it's perfect and it never is. The longer I leave it the more I modify it.

I worked out I need pogo pins about 11-13mm high above the PCB that will compress down to about 10mm, if there is such a thing. That'll be on my to-do shopping list.

The files were uploaded to the groups.io/ET-3400 web site here:

https://groups.io/g/ET-3400/files/5.%20Projects/ET-3400%20ROM%20Replacement%20SMD%20design

you will need a log in to access them, but even Google login should work.

I won't have PCBs before the end of the RetroChallenge but that was never going to happen.

I've decided to add an extra task to my project in the remaining time.

I am going to write a small program in 6800 code using the examples given in the ET-3400 manuals as a basis. I haven't done much 6800 programming and haven't setup any assembler for 6800 yet so we'll see how it goes. If it works I plan to burn the code into the EEPROM in my prototype setup as an 8K ROM, not that I will use much of that. But why not use the space for practice.

I'm hoping to have a very short video at the end of this, but if not just still images...


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