ALU - adder/subtractor module

PCB artwork

• Top copper layer
• Bottom copper layer
• Both copper layers (previous two PDFs combined)
• Silk screen

Progress pictures

Progress shot of the schematic and PCB design.

The PCB toner transfer was mostly successful. The result is salvageable by passing over broken and hair-thin traces with a sharpie. Also painted over holes in the ground plane which is definitely not required, but I thought they might be confusing while drilling later (and ugly).

After etching, the PCB looks usable. Sharpie fixups definitely worked; might need some solder touchups here and there to fix broken traces.

Running a few manual tests with DIP-switches and LEDs, after completing the assembly of the adder board.