S100 Computers

Home S-100 Boards History New Boards Software Boards For Sale
Forum Other Web Sites News Index    
Memory Merchant 
- 64K Static RAM Board
This was a fairly traditional 64K static  RAM board for the time with some extra features added in.


The board used 2K X 8-bit RAM (150 nsec.) chips. Typical chips were NEC UPD4016-3's,  Hitachi HM6116P-3's, or Mitsubishi M585725P's. Speed was in excess of 6 MHz. The board ran with low power requirements. (435 Ma. max. — loaded with 64K).  The board had Cromemco style Bank Select and Extended Addressing.  It also had a 2K window which can be placed anywhere in the 64K memory map.  It had independently addressable 16K blocks organized as:-

Two independent 32K banks
One 64K Extended Address Page
One 48K and one 16K bank for use with MP/M.

Each 32K bank responded independently to the phantom line.
2716 (5V) EPROMS could replace any or all of the RAM.
The board had field-proven operation in CROMEMCO CROMIX and CDOS.
It also was compatible with EEE 696 systems such as Northstar, CompuPro, Morrow, IMS, IMSAI front panel, Altair and many others.

The manual for this board can be obtained here.


Memory Merchant    S-100 Boards
16K Static RAM    64K Static RAM


This page was last modified on 10/25/2013