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Solid State Music - VB1B
This was a very reliable and popular video display card in the early days of the S-100 bus. Many early memory mapped video games were run from either this card or the Processor Technology VDM-1


The board displayed 64 (or 32) characters per line with 16 lines per display.  It could be set to graphic mode where 128X48 pixels could be displayed.  The character generator was the Motorola MCM6571A.   The four pins on the top left hand corner put out H & V Sync signals along with the video itself and a ground line.  There was also a connection for composite video.  Memory was eight 2102L's. The RAM could reside at any 1K boundary within the 64K address space.
There was no phantom line but if you removed U41 and bent up pins 11 and 13 of U28 you could overlap the memory with any other RAM card you had in your system. These were the output drivers on to the bus.
The excellent manual for this board can be seen here


Other Solid State Music S-100 Boards
8K RAM    VB1B   8080 CPU   Z80 CPU    EPROM   IO4    PB1    VB3    IO5   16K RAM    16K (MB10) RAM


This page was last modified on 05/11/2020