Post Reply 
Found these inside a non-working 71B
11-18-2020, 07:01 PM
Post: #142
RE: Found these inside a non-working 71B
I made my adapter from a 4K module. I removed all the chips off the little circuit card inside and removed all of the copper trace that I could until I was left with a bare board with just the bus connector pins. I then cut a hole in the front of the shell to fit a small pitch connector, glued in the connector and wired it up to the pins of the bus connector. Initially when I did this my main purpose was to make up a plugin to disable the onboard OS ROMs so I could use a later version loaded on a FRAM module, but I was also curious about the signal timing so I expanded its function.

You can also pick up all of the bus signals on the pins for the card reader, and those have the advantage of being on the same board as the CPU which could come in handy if you have a connection problem between the CPU card and the memory / I/O card.

Paul.
Find all posts by this user
Quote this message in a reply
Post Reply 


Messages In This Thread
What's U10? - Dave Frederickson - 03-15-2018, 03:43 PM
RE: Found these inside a non-working 71B - Paul Berger (Canada) - 11-18-2020 07:01 PM



User(s) browsing this thread: 2 Guest(s)