Hardware version 3 represents the move from breadboards (20 of them!) to a PCB. Most everything is the same as in version 2, except for the following:

• Removal of the external control interface previously used for in-system flash programming via an Arduino. This is made obsolete by ZIF-socketed flash chips that can be programmed directly (and faster, too!).
• Optimizations of Boolean control logic to reduce overall chip count.

Schematics

• schematic-v3-revA.pdf: Schematic diagrams for the main computer board
• kicad/: KiCad files for this schematic as well as the PCB design
• [TODO: schematics for I/O expansion: keyboard buffer, LCD, and hardware timer]

PCB

• kicad/: KiCad files for the schematic and PCB design
• gerber-v3-revA/: Gerber files for PCB revision A
• pcb-v3-revA.pdf: PDF of the PCB design provided for viewing

Other documentation

[TODO]

Software

See ../software/. Software is binary-compatible with version 2.