KA410 MicroVAX 2000/VAXstation 2000 System Module

From Computer History Wiki
Jump to: navigation, search


There are two versions of the KA410 MicroVAX 2000/VAXstation 2000 System Module:

  • KA410-A: MicroVAX 2000
  • KA410-B: VAXstation 2000

The KA410 system module is central to the entire MicroVAX 2000/VAXstation 2000 computer system. It is a printed circuit board mounted on the FCC shield. The system module contains all the control and interface electronics needed to support the CPU chip, support all I/O for the disks and tapes, support the video subsystem, and support the three option ports (memory, Ethernet network, and a graphics option port). This system module contains 2 megabytes of RAM and is used in both the VAXstation 2000 and MicroVAX 2000 systems. A jumper setting on the system module determines which system it is configured for. The system jumper sets a bit in the configuration and test register. [1]

KA410 MicroVAX 2000/VAXstation 2000 System Module

The KA410 MicroVAX 2000/VAXstation 2000 System Module contains:

  • Central processor (DC333 MicroVAX CPU chip and DC337 MicroVAX FPU chip)
  • ROM memory
  • Time-of-Year clock
  • DC524 Standard cell
  • DC503 Cursor sprite chip
  • DC367B Serial line controller
  • 9224 Disk controller (up to one diskette drive and two hard disk drives)
  • NCR 5380 TK50Z Tape controller (restricted function SCSI)
  • ThinWire Ethernet circuits (Transceiver function circuitry)
  • Miscellaneous registers

System ROM Sets

There are at least five known System ROM Sets (four ICs 64kx8 27512 each):

  • 23-001E7, 23-002E7, 23-003E7, 23-004E7
  • 23-033E7, 23-034E7, 23-035E7, 23-036E7
  • 23-050E7, 23-051E7, 23-052E7, 23-053E7: ROM V2.1
  • 23-092E7, 23-093E7, 23-094E7, 23-095E7: ROM V2.2
  • (Order numbers yet unknown): ROM V2.3 is used by the SIMH microvax2000 simulator

There are probably some changes in ROM functionality, but there is very little known as of yet:

Power Requirements

The system module requires +12 Vdc, +5 Vdc, and -12 Vdc supplies for operation and a special -9 Vdc for power loading at 180 milliamps for the ThinWire Ethernet transceiver circuits on the system module.


[1] VAXstation 2000 and MicroVAX 2000 Technical Manual. EK-VTTAA-TM.001

External links