The Motorola 6800 was an 8-bit microprocessor introduced in 1974. It had a 16-bit address bus and 8-bit data bus. The 6800 architecture included six registers - two 8-bit accumulators, three 16-bit registers for the program counter, stack pointer, and index register, and an 8-bit status register. It supported seven addressing modes and had 72 instructions. The document provides details on the 6800 register set, addressing modes, and architecture.