# VAXstation 3520 and 3540

## Multiple CVAX Processors

The VAXstation 35x0 is a symmetric multiprocessor, graphics workstation that was introduced by Digital Equipment Corporation in January 1989. The 3520 is a two-processor configuration, and the 3540 is the same system configured with four-processors. The CPUs are CMOS VAX microprocessors running at 80ns cycle time. The processors are benchmarked at 2.7 VUP each.

The multifunction I/O module attaches a SCSI bus, Ethernet, and four serial ports. A Q-bus adapter is also available as an option.

The graphics board contains a dedicated graphics co-processor, which is aided by a 3D Geometry Accelerator. The base system uses 8-plane color, which can be expanded to 24-planes. The 19" RGB monitor has a resolution of 1280 x 1024 pixels.

These systems support motion in three dimensions, smooth shading, depth cueing, and true (24-bit) color display in hardware. The image display is double-buffered, and can be used concurrently with a 24-bit Z-buffer for hidden-surface calculations for solids modeling applications.

VAXstation 3540 backplane configuration
Slot | Module | Description | M-bus id (Nexus)
--- | --- | --- | ---
part # | option
ps | H7868-A | first power supply
1 | L2006 | VCB03 | 16-plane graphics
2 | L2005 | LEGSS | 8-plane graphics
3 | L2004 | LEGSS | base graphics | 7
4 | L2003 |  | multifunction I/O | 5
5 | L2007 | MS60 | 16MB ECC memory | 4
6 | L2001 | KA60 | dual SMP CPU | 3
7 | L2001 | KA60 | dual SMP CPU | 2
8 | L2007 | MS60 | 16MB ECC memory | 1
9 | L2008 | VS60B | TQK70 adapter | 0
10 | M7559 | TQK70 | TK70 controller | Q-bus slots
11 | - | - | empty
12 | - | - | empty
ps | H7868-A | second power supply

## FireFox backplane

During the design and development of the 35x0 it was known by the codename FireFox. A vestige of this name can be seen behind the right hand power supply - there is an etch that reads `FIREFOX BACKPLANE` next to the socket for slot number one.

Some of the backplane slots are dual-function; slot number 6 can take a dual CPU module or a memory array. Other slots are reserved; the graphics boards occupy slots 1 through 3. Slot 9 can take a Q-bus adapter, which provides a communications link to quad-height Q-bus modules in slots 10 through 12.

The architecture of the backplane is called the M-bus. Processors, memory arrays, and I/O adapters connect to this system bus. An attachment point is known as a Nexus.

The slots are vertical, and are numbered from right to left. They are housed in a 27" high BA213 cabinet which measures 21" wide by 17.8" deep. The front panel of the card cage contains connectors for the RGB monitor, mouse/keyboard, modem, serial printer and switchable AUI/BNC Ethernet. Above the cards there are four bays for full-height SCSI devices, one of which is accesible through the front panel for a tape cartridge drive. There is a connector for SCSI expansion, a DC indicator light, and switches for Restart/Run and Halt.

## Details about the VAXstation 35x0

- DEC's product description for the VAXstation 3520 and 3540
- Part numbers for VAXstation 35x0 documentation and modules
- A short guide to some of the console commands and diagnostics
- Another DEC product description

## Related information

- VAX Hardware Archive
- Jim Agnew maintains a MicroVAX/VAXstation FAQ
- Comments about the VAXstation 3520/3540
- Digital's Computing Timeline contains information about the CMOS VAX chip

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last modified: 10-OCT-2002