The random access memory (RAM) stores the program the computer is executing as well as any data the program needs. Our breadboard computer uses 4-bit addresses which means it will only have 16 bytes of RAM, limiting the size and complexity of programs it can run. This is by far its biggest limitation.

Videos

Schematic

(coming soon!)

Parts list

QuantityDescription
3Breadboard
31kΩ resistor
10.01µF capacitor
174LS00 (Quad NAND gate)
274LS04 (Hex inverter)
474LS157 (Quad 2-to-1 line data selector)
174LS173 (4-bit D-type register)
274LS189 (64-bit random access memory)
174LS245 (Octal bus transceiver)
1Double-throw toggle switch
1Momentary 6mm tact switch
18-position DIP switch
14-position DIP switch
9Red LED
4Yellow LED
1Green LED