VCB02 Video Controller

The VCB02 Video Controller (also sometimes called the QDSS) is a QBUS bit-mapped display option, a successor to the VCB01 Video Controller. It is a 1/4/8 plane video subsystem, providing 1024x864 resolution.

It used the Q22 version of the QBUS, and consisted of a number of quad-height modules.

The VCB02 also provided several basic I/O functions, including:

VCB02 Modules

Module	Description
M7615	Quad Monochrome Graphics Module
M7168	Quad 4 Plane Color Bitmap
M7169	Quad Q22 Bus Video Controller Module

VCB02 Option		M7615	M7168	M7169
-A	Mono 1 Plane (B/W)	1	-	-
-B	Color 4 Plane	-	1	1
-C	Color 8 Plane	-	2	1
-D	Mono 4 Plane	-	1	1
-E	Mono 8 Plane	-	2	1
-F	Upgrade 4 to 8 Plane	-	1	-

1 Plane allows black/white graphics.

4 Planes allow for 16 colors / resp. 16 shades of gray from a palette of 16.7 million.

8 Planes allow for 256 colors / resp. 256 shades of gray from a palette of 16.7 million.

The only difference between the 4/8 Plane Color and Mono versions are the bulkhead assemblies; DEC part numbers:

In the times of the MicroVAX II, the smaller BA23 enclosure supported only the 4 Plane VCB02 options.

To use the 8 Plane options you had to use the bigger BA123 enclosure.

This restriction was due to problems with the BA23 power supply and cooling.

For the VAXstation 3200, the BA23 power supply as well as cooling were improved so that the restriction was removed.

Initially the VCB02 was delivered with one of the two types of monitors:

VR160 19" 1024 x 864 Monochrome Monitor; connected with a BC18P-10 Monochrome Cable
VR290 19" 1024 x 864 Color Monitor; connected with a BC18Z-10 Color Cable

More monitor models were added lateron, e.g. the VR299

The VCB02 was used with the following VAXstation models: