A revolutionary microprocessor designed and marketed by Intel in 1972. It was followed by the 8085, 8086, and 8088. In addition to the 8080, a system needed support circuitry in the form of the 8228 (a fancy multiplexor) and a 8224 (a crystal oscillator with some fancy operations).

The internal block diagram consists of a Control Unit, Register Array, and Aritmetic and Logic Unit, plus a Data Bus, Control Bus, and Address Bus

Control Unit - Consists of the Instruction Register, Instruction Decoder, Timing and Control, and Data Buffer/Data Bus Multiplexor.

Register Array - Consists of eight 8-bit registers named: W, Z, B, C, D, E, H, L and four 16 bit resgisters: the Program Counter, Stack Counter, and Incrementer Decrementer Address Latch.

Aritmetic and Logic Unit - Consists of the ALU, plus three 8-bit registers: the Accumulator, the Temporary Register, and the Flag Register.

The Data Bus is Bi-directional and is 8-bits, used to transfer data to and from memory.

The Control bus generates a single active siganl at a time to control active units.

The Address is Uni-directional and is 16-bits, used to select active addresses om memory.

The 8224 generates an 18MHz clock pulse, but this is slowed to 2MHz. the 8224 also has two active out of phase outputs to provide twice the number of pulse edges for faster internal operation speeds.

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