The RP/RF/RJ5C15 are real-time clocks for microcomputers that can be connected directly to data buses of16bit CPUs, such as the 8086, Z8000, and 68000, and of 8bit CPUs, such as the 8085A, Z80, 6809, and 6502. Theyallow setting or reading of the clock with the same procedures as for the Read/Write operation for memory.These products have various features including clock, calendar and alarm functions and can be backed up bybatteries.