VAX Simulator Configuration

The VAX was the most popular 32-bit minicomputer. Introduced by DEC in 1977, it remained in active production until 1999. The VAX family included many processor designs:

While the relationship between processor designs and system models is obvious for TTL and ECL processors, the VAX microprocessors were used in many different types and models of systems. For example, CVAX was the basis for the MicroVAX 3500, the VAX and VAXstation 3100, and the VAX 6200. A complete chart of the VAX processors and their instruction sets and system implementations can be found here.

SimH supports two different VAX models: the VAX-11/780 and the MicroVAX 3900.  The options for the VAX-11/780 are:

Option Description Capacity
CPU VAX-11/780, no FPA, G&H microcode
Memory 2 x MS780-C controller, or 8MB
2 x MS780-E controller 16MB-128MB
Console Full duplex asynchronous interface        
Single-density floppy disk drive 256KB
Real time clock VAX standard real-time and TOY clock
Card reader CR11/CD11
Line printer LP11 line printer
Terminal multiplexor   DZ11 multiplexor 8-32 lines
Disk RL11/RL01-RL02 cartridge disk 5-10MB
RK611/RK06-RK07 cartridge disk 14-28MB
UDA50/RX50,RX33 floppy disks .4-1.2MB
UDA50/RD51,RD52,RD53,RD54,RD31 disks 10.8-155.6MB
UDA50/RA60,RA71,RA72,RA73,RA81,RA82,RA90,RA92 disks 12KB
RH780/RP04/5,RP06,RM02/3,RM80,RP07 67-516MB
Floppy disk RX211/RX02 floppy disk 512KB
Magnetic tape TS11 1600bpi 9 track magnetic tape
TUK50/TK50 TMSCP magnetic tape
RH780/TM03/TE16,TU45,TU77 800/1600bpi 9 track magnetic tape
Network DEUNA/DELUA Ethernet controller

The options for the MicroVAX 3900 are:
Option Description Capacity
CPU and memory      MicroVAX 3900 (CVAX CPU) 16MB - 64MB
Console Full duplex asynchronous interface          
Real time clock VAX standard real-time and TOY clock
Card reader CR11/CD11 card reader
Line printer LPV11 line printer
Terminal multiplexor DZV11 multiplexor 4-16 lines
DHQ11 multiplexor 8-32 lines
Disk RLV12/RL01-RL02 cartridge disk 5-10MB
RQDX3/RX50,RX33 floppy disks .4-1.2MB
RQDX3/RD51,RD52,RD53,RD54,RD31 disks 10.8-155.6MB
RQDX3/RA60,RA71,RA72,RA73,RA81,RA82,RA90,RA92 disks   200-1960MB
Floppy disk RXV21/RX02 floppy disk 512KB
Magnetic tape TSV05 1600bpi 9 track magnetic tape
TQK50/TK50 TMSCP magnetic tape
Network DELQA/DEQNA Ethernet controller


Updated 08-Aug-2020 by Bob Supnik (simh AT groups DOT io - anti-spam encoded)