8 Bit Computer

Addition and Subtraction in a Digital Circuit

组合逻辑电路基础,低位的进位,向高位的进位,input:A B  Cin,output: Q Cout

Architecture

The clock unit is an oscillator circuit, creating a clock signal which paces all operations of the computer and therefore synchronizes the data transfer between units. When given the command, it inhibits this clock signal, thus halts all operations of the computer. The clock unit is different from all other units as it does not transfer any data.

Memory is a collection of registers. Every register, now called memory location, has an address through which it can be accessed. Memory is only used in the memory unit (MU), which is the unit that stores the program running on the computer. The memory unit consists of two parts, the aforementioned memory with 16 memory locations and a memory address register (MAR). The memory address register is 4 bits in size and stores the address of the currently accessed memory location.

 program counter unit (PCU)

 instruction register (IR) and a controller-sequencer