6803

6803 refers to a family of 8-bit microcontrollers in Motorola's 6800 line, most prominently the MC6803. Introduced in the late 1970s and produced through the 1980s, these devices combined a 6800-compatible central processor with on-chip RAM and peripheral I/O in a single chip, designed for embedded control applications. Program code was usually stored in external ROM or PROM.

The devices use an 8-bit data bus with 8-bit accumulators A and B, a 16-bit program counter, a 16-bit index register, a stack pointer, and a condition-code register. The core executes 6800-family instructions with similar timing. They include on-chip RAM and a set of I/O lines and a programmable timer, with interrupts supported at multiple maskable levels. An external clock drives operation.

6803 devices form part of the MC6800 family alongside related parts such as the MC6800, MC6801, and MC6802, and led to later 68HC variants. The 6803 retained software compatibility with the 6800 instruction set while integrating RAM and I/O to reduce the required external components.

Applications were primarily in embedded control for household appliances, automotive modules, consumer electronics, and industrial equipment, where the combination of CPU, RAM, and I/O on one chip offered cost and space advantages.

Over time Motorola and successors introduced more integrated and higher-performance 8-bit controllers in the 68HC family, and the 6800 line gradually declined in use during the late 1980s and 1990s as newer microcontroller architectures emerged.