Intel 8080 family

The Intel 8080/8080A was not object-code compatible with the 8008, but it was source-code compatible with it. The 8080 CPU had the same interrupt processing logic as the 8008, which made porting of old applications easier. Maximum memory size on the Intel 8080 was increased from 16 KB to 64 KB. The number of I/O ports was increased to 256. In addition to all 8008 instructions and addressing modes the 8080 processor included many new instructions and direct addressing mode. The 8080 also included new Stack Pointer (SP) register. The SP was used to specify position of external stack in CPU memory, and the stack could grow as large as the size of memory. Thus, the CPU was no longer limited to 7-level internal stack, like the 8008 did.

The Intel 8080 microprocessor was very popular and was second-sourced by many manufacturers. Clones of the 8080 processor were made in USSR, Poland, CSSR, Hungary and Romania.