MCP-1600

The MCP-1600 was a multi-chip microprocessor made by Western Digital in the late 1970s through the early 1980s. Used in the Pascal MicroEngine, the original Alpha Microsystems AM-100, and the DEC LSI-11 microcomputer, a cost-reduced and compact implementation of the DEC PDP-11.

There were three types of chips in the chip-set:

• CP1611 RALU - Register ALU chip
• CP1621 CON - Control chip
• CP1631 MICROM - Mask-programmed microcode ROM chip (512 – 22 bit words)

The chips used a 3.3MHz four phase clock and four power supply voltages (+5V, +12V, -12V, and -5V). Internally the MCP-1600 was a (relatively fast) 8-bit processor that could be micro-programmed to emulate a 16-bit CPU. Up to four MICROMs were supported, but usually two or three could hold the needed microprogram for a processor.

• Die photos from LSI-11 chip set
• 
  CP1611 RALU chip
• 
  CP1621 Control chip
• 
  CP1631 MICROM chip

External links

• http://www.antiquetech.com/?page_id=782
• "Western Digital adds MCP-1600 Micro". Computerworld. 26 November 1975.