|
The CDP1802 aka RCA COSMAC is an 8-bit microprocessor developed by RCA and presently manufactured by Harris Semiconductor, designed for embedded applications. It was one of the first radiation-hardened microprocessors, and was used widely in satellites and space probes.
The 1802 has a static CMOS design with no minimum clock frequency, so that it can be run at very low speeds and low power. It has an 8-bit parallel bus with a bidirectional data bus and a multiplexed address bus. It has a bit-programmable output port, and four input pins which are directly tested by branch instructions. It's I/O mode is flexible and programmable, and it has a single-phase clock with an on-chip oscillator. It's register set consists of sixteen 16-bit registers. The program counter (PC) can be any of these, providing a simple way to implement multiple PCs, pointers, or registers.
This processor, which was actually the one-chip implementation of the earlier two-chip CDP1801, was used for several early computers, such as the COSMAC ELF, COSMAC VIP, Quest Super Elf, and Netronics ELF II. It was also used in the Voyager, Viking, and Galileo space probes.
External links
|
