David's First Computer
1981-1982
The "front panel" with dip switches for address and data.
This computer started out with no ROM.
The program had to be entered in binary using the dip switches.
It took over 200 bytes before the keypad could be used to
enter the rest of the program in hexadecimal.
The CPU board.
The computer busses consist of wire wrap sockets that allow the boards to be stacked.
The 2708 ROM can be seen on the lower right with the 1k of ram to its left.
Flip side of "front pannel" board.
The board was wired using the Vector wiring pencil using 36 guage wire with
solder through insulation. Spacers hold the wires in place.
The program.
Only the first page was produced with a typewriter.
The rest of the pages were written with a pencil.
All of the program was assembled by hand.
Schematic of CPU.
Here is the schematic of the CPU board.
The memory is on another page.
