S100 Computers

Home S-100 Boards History New Boards Software Boards For Sale
Forum Other Web Sites News Index    
Dual Systems --  EPROM-32/64K    EPROM Board

The EPROM-32/64K EPROM/ROM board provided for permanent (non-volatile) storage of up to 64K bytes of data, The sixteen on-board sockets accept either industry-standard 2716 or 2732 EPROMS.

Dual Systems EPROM board

The EPROM-32/64K could also be used as a RAM board when type 6116 RAM ICs are installed, in place of 2716 EPROMS. RAMS and EPROMS (type 2716 only) could in fact be mixed, allowing the board to function as a 32KB RAM/ROM board.

Depending on the state of the SXTRQ (sixteen request) line on the IEEE 696/S-100 bus, data could be read from the EPROM-32/64K board either a byte at a time, or as 16-bit words. EPROMS/ROMS were installed in pairs, one in the upper row on the board, and one in the lower row. When a 16-bit data transfer was required, the most significant 8 bits were read from one row while the least significant 8 bits was read simultaneously from the other row. If an 8-bit transfer was required, data was read from either the upper row or the lower depending on whether A0 was high (ODD ADDRESS) or low (EVEN ADDRESS).

There was extended memory addressing through 24-bit address lines as well as standard 16 bit addressing.  The board was switch selectable to any 4K boundary. An on-board wait state generator allowed the board to function with clock speeds from 2-8MHz.

Note the picture above shows the board without the battery power standby option.

I cannot locate a manual for this board. If you would like to share one please let me know.


Other Dual Systems S-100 Boards
68000 CPU    256K RAM    Clock Board   CMEM-RAM    Digital-to-Analog    Analog-to Digital    4SIO    EPROM


This page was last modified on 10/25/2013