Main Board Schematics

These are the schematics I used during construction of the main board. They are simple scans of hand-drawn diagrams. The originals are pencil on notebook paper, and may be a little hard to read in places, especially if I erased something and drew it again. I may replace these with proper graphics drawings, but for now this is all I have.

Register Write Pulse Design
Inverter/Clock Pulse Delay
Write Pulse Register
Memory Write Signal Design
Signal Inverter
Carry and Memory Write Flip-Flops
PC and Address Source Multiplexors
'244 Data Bus Buffer and Zero Logic 1
Zero Logic 2
Registers
Accumulator and ALU A Source Multiplexors
Accumulator Extra (top 4) Bits
ALU B and Operation Source Multiplexors
Layout, top
Layout, bottom

© Donn Stewart 2004