Monday, May 7, 2012

16K Memory Card Progress

I've now wired up most of the memory board for the Replica 1. I started with the address decoding and control lines and confirmed that it worked (e.g reading addresses in the correct range generated appropriate chip select signals as observed on an oscilloscope).

Testing Address Decoding
I then wired up the first of the two EEPROM/RAM sockets and confirmed that it is working, both with EEPROM and RAM chips. I now need to wire up the second memory chip socket.

Component Side

The wiring is rather tedious and time consuming. I might consider wirewrap for future projects, although the end result doesn't look as attractive with the big wirewrap pins sticking out of the back of the board.

Wiring Side

I'm also continuing to tweak the Apple 1 BASIC source, adding comments.

No comments: