VIDC1


The VIDC1 was a Video Display Controller chip created as an accompanying chip to the ARM CPU as used in Acorn Archimedes computer systems, its successor the VIDC20 was used in the later RiscPCs.

Video

The VIDC1 can use a color depth of 1, 2, 4 or eight bits per color, from monochrome to 4 to 16 to 256 colors. Also included is a very small color lookup table, just 16 12-bit words,. The 12 bits were split in three 4-bit RGB values, with a 4-bit high speed D-A converter for each of the three primary colors. Its single "sprite" was used for a hardware mouse pointer, which could have three different colors. The timing generator was fully programmable, and could be clocked with an 8 to 24 MHz clock. Resolutions that could be supported were 1024x1024 in monochrome, 640x512 in 16 colors, or 640x256 in 256 colors.

Sound

The VDC also supported eight-channel stereo logarithmic 8-bit PWM sound.