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Digital MicroVAX 3500 - AKVAX - zxnet


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akvax - MicroVAX 3500

System Information
Manufacturer: Digital Equipment Corporation (DEC)
Model: MicroVAX 3500 (VMS Reports it as an 3800 due to upgraded CPU)
Hostname: akvax Address:
CPU: DEC KA655 (CVAX) RAM: 32MB in two boards
System Software: DEC VAX/VMS: Compaq OpenVMS v7.3
Software: MACRO32, DEC C
Services: Telnet (Local Access Only)

This VAX started life at the Department of Scientific and Industrial Research as "AKV" in auckland during the late 80s. It then moved to Hort+Research when DSIR was split up in the 90s. It remained in service at Hort+Research until at least the late 90s. It was not the original machine to be called "AKV" - it replaced a VAX-11/780 of the same name.

This was my first ever VAX which I purchased from someone in Auckland in May 2008. It remained in storage at my house from then until November 2008 when I finally had time to wire up the required serial port adapter cables. It started just fine the first time and I was able to install OpenVMS 7.3 on it the following day.

The machine was not in perfect condition when I got it. The battery backup unit had been leaking behind the CPU cover panel for some time and has made a bit of a mess of that area of the case. No damage appears to have been done by the battery and it was removed within a few weeks of getting the machine.

Aside from the TK70, the machine has no drives installed. It currently boots from external SCSI drives in a BA350-series storageworks enclosure. The machine was configured with the following boards when I got it. I have not changed any of this.

Slot: Module: Option: Description:
1 M7625 KA655 KA655 CPU board
2 M7622 MS650-BA 16-MByte MOS RAM for KA650
3 M7622 MS650-BA 16-MByte MOS RAM for KA650
4 M7516 DELQA Ethernet Interface
5AB CMD CQD-200/M (MSCP) SCSI Controller
5CD Empty
6AB M9047 Grant continuity card
6CD Empty
7AB M7559 TQK70 TMSCP controller for TK70
7CD 74-33507-01 blank plastic card (Dual height module spacer panel)
8AB Webster Computer Corp. WQDHV/02???
8CD Webster Computer Corp. WQDHV/02??? (probably just holding up above card)
9AB CMD CQD-220/TM (TMSCP & MSCP) SCSI Controller
9CD M9047 Grant Continuity Card (probably just holding up above card)
10 Empty (missing front case panel)
11 Empty (missing front case panel)
12 Empty (missing front case panel)

Slot numbers link to a photo of the board from that slot. Pictures of components installed in the case are also available.

The below system information was taken when I first powered on the machine. The only changes since then is a few DUA entries under show device.
System Configuration
>>>show bflg
>>>show boot
>>>show device
UQSSP Disk Controller 0 (772150)

UQSSP Tape Controller 0 (774500)
-MUA0 (TK70)

Ethernet Adapter 0 (774440)
>>>show ethernet
Ethernet Adapter 0 (774440)
-XQA0 (08-00-2B-0E-29-9F)
>>>show language
English (United States/Canada)
>>>show memory /full
Memory 0: 00000000 to 00FFFFFF, 16MB, 0 bad pages
Memory 1: 01000000 to 01FFFFFF, 16MB, 0 bad pages

Total of 32MB, 0 bad pages, 112 reserved pages

Memory Bitmap
-01FF2000 to 01FF3FFF, 16 pages

Console Scratch Area
-01FF4000 to 01FF7FFF, 32 pages

Qbus Map
-01FF8000 to 01FFFFFF, 64 pages

Scan of Bad Pages
>>show qbus
Scan of Qbus I/O Space
-20000124 (760444) = 0000
-20000126 (760446) = 0B40
-20000140 (760500) = 0080 (300)
-20000142 (760502) = F081
-20000144 (760504) = DD18
-20000146 (760506) = 0000
-20000148 (760510) = 0000
-2000014A (760512) = 0000
-2000014C (760514) = 8000
-2000014E (760516) = 0000
-20000150 (760520) = 0080
-20000152 (760522) = F081
-20000154 (760524) = DD18
-20000156 (760526) = 0000
-20000158 (760530) = 0000
-2000015A (760532) = 0000
-2000015C (760534) = 8000
-2000015E (760536) = 0000
-20001468 (772150) = 0000 (154) RQDX3/KDA50/RRD50/RQC25/KFQSA-DISK
-2000146A (772152) = 0B00
-20001920 (774440) = FF08 (120) DELQA/DEQNA/DESQA
-20001922 (774442) = FF00
-20001924 (774444) = FF2B
-20001926 (774446) = FF0E
-20001928 (774450) = FF29
-2000192A (774452) = FF9F
-2000192C (774454) = 8000
-2000192E (774456) = 1030
-20001940 (774500) = 0000 (260) TQK50/TQK70/TU81E/RV20/KFQSA-TAPE
-20001942 (774502) = 0BC0
-20001F40 (777500) = 0020 (004) IPCR

Scan of Qbus Memory Space
>>>show rlv12
>>>show uqssp
UQSSP Disk Controller 0 (772150)

UQSSP Tape Controller 0 (774500)
-MUA0 (TK70)
>>>show version
KA655-A V5.3, VMB 2.7

To Do


Plenty of terrible images of the machine like the ones below are available here.
[Front of MV3500 with cover on] [Front of MV3500 with cover off] [Front of system with panels removed]