Registers

Most CPUs have a number of registers which store small amounts of data that the CPU is processing. In our simple breadboard CPU, we’ll build three 8-bit registers: A, B, and IR. The A and B registers are general-purpose registers. IR (the instruction register) works similarly, but we’ll only use it for storing the current instruction that’s being executed.

Videos

Bus architecture and how register transfers work - 8 bit register - Part 1
Tri-state logic: Connecting multiple outputs together - 8 bit register - Part 2
Designing and building a 1-bit register - 8 bit register - Part 3
Building an 8-bit register - 8-bit register - Part 4
Testing our computer's registers - 8-bit register - Part 5

Schematic: A register

Schematic of the A register

Schematic: B register

Schematic of the B register

Schematic: Instruction register

Schematic of the instruction register

Data sheet

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