Home‎ > ‎Small Systems Collection‎ > ‎

DECmate II

The PC278-A DECmate II was introduced in 1982 as one of three DEC systems to compete with the IBM PC. All DECmate II systems contained at least one 400 KB 5.25 inch RX50 floppy disk drive.  These systems used an 8 MHz Harris 6120 CMOS PDP-8 processor chip, and had 32K words of RAM for use by programs, and an additional 32K words for programs for device emulation software (slushware).

The DECmate II could be expanded by adding another RX50 floppy disk drive. By adding an RX78 board one or two RX01 or RX02 8 inch floppy disk drives could be added. An MFM disk controller could also be added to support a 5.25 inch hard disk drive. The RX78 floppy controller and the hard disk contoller need to be installed in the center location so only one can be used.

An APU coprocessor board could be added in the right slot to allow it to run CP/M. Three different coprocessor boards were available, one with a Z80 and 64KB RAM, and a two boards with both a Z80 and an Intel 8086. One of the Z80/8086 boards has 256KB RAM and one had 512 KB RAM. A wide variety of CP/M-2.2 software could be run on this system when the APU was installed.
A graphics board that supports a color monitor could be installed in the left location.

The DECmate II was withdrawn in 1986 and replaced by the DECmate III.
This system contains one RX50 floppy drive, one RD51 hard disk, and a Z80 APU board. It has the WPS word processing software loaded.
A DECmate II with the Hard Disk option. The incorrect keyboard is shown. The correct PC2K1-AA keyboard has blue trim and special WPS markings on the keys.
Click on the image for a larger view.
The DECmate II motherboard. The connectors at the middle-right are for the RX-50 floppy drives.
 Click on the image for a larger view.
The DECmate II mother board with the RD50/51 hard disk controller installed in the middle location. A PC27X-BA RX01/RX02 interface board can also be installed in the middle location. A PC27X-AA CP/M-80 APU is installed in the right location. A graphics board can be installed in the left location. 
Click on the image for a larger view.