The schematics...

This is the schematic for the CPU board of my TinkerBug 6809 computer. It is basically the board that Frank Wilson designed and that was published in The Computer Journal way back when. I have modified it slightly and added the 74LS138 circuit to allow me to select up to 8 I/O devices. Otherwise it is pretty much Frank's design. I re-wrote the monitor code to suit my needs. I kept the bit-banging code to drive the PIA as a serial port.

This is an idea I have for a backplane PCB. It's not the one I'm using now although the basic circuit is very similar. The power connector (J1 & J2) is wired up to work with an old AT-style PC power supply.


Here is the schematic for the ATA/IDE board I am working on. It is still a work in progress and this circuit may change if the need comes up.

This is the circuit for the Floppy Controller board I use. It is from an old Swedish publication and has its share of errors. Those errors cost me many hours of troubleshooting before I got the thing to work properly. I am in the process of re-drawing this so once I have that done I will post it here.