COP421 reader finished!

 I finished building my COP421 reader and it seems to work perfectly.

I confirmed that the Halcyon COP421 program is identical to the dump that Mark Broadhead made over 20 years ago of the arcade Thayer's Quest COP421 program.

I uploaded everything (source code, CAD files, etc) to github, which you can find here: https://github.com/rulecity/COP421Reader/

Building a COP421 reader

 

Just to be sure I get every last detail that I can from the Halcyon that I have on loan, I've decided to follow the excellent instructions from here ( http://john.ccac.rwth-aachen.de:8000/patrick/COPSreader.htm ) and create my own COP reader to read Halcyon's COP chip.  Now, I am 90% sure it will be the same one as on Thayer's Quest arcade, but I need to make 100% sure.  I could use the same device as in the link, but I think it will be more fun/challenging to create my own.  I am re-using some parts that I've already used with Dexter since I'm more familiar with them (mainly the FT232 USB IC and the ATMega644p microcontroller at 18.432 MHz).