Solid State Music - VB3
Video Display Board This was the follow-on board to their
successful VB1
The VB3 was a memory mapped video
display board that provided a flexible video display system for S-100 bus
computers.
A maximum of 4096 bytes of contiguous memory could be directly mapped to the
screen as characters or graphics.
The display could be programmed for up to fifty 80-character lines (or 51 on
European standard monitors) featuring upper and lower case letters with
discerners. Optionally, the user may display 20, 32, 40, 64, 72, 96, and 132
characters per line using optional mapping PROMs available at extra cost from
SSM.
The VB3A features a second RAM block in
addition to the video RAM which contains "attribute" bytes to control the
display of each individual character. These attributes allow any individual
character to appear as a standard alphanumeric upper/lower case font or an
alternate user-programmed font. (SSM included one alternate character font with
the VB3. This was a 6 x 7 matrix character set for displaying the maximum number
of text lines using the lowest number of raster lines possible.) In addition,
the character may be displayed in normal or low intensity, reverse video (black
on white), with an underscore or strike-through mark, blinking, blanked, or as a
thin line or dot graphics.
The manual for this board may be
obtained here. Jon Bondy wrote a nice review of this board in March
1981 for Microsystems (Vol 2, #2, p26). It can he seen
here.
