System Module

System Modules (originally known as System Building Blocks; the name was changed around 1961) are a DEC modular digital logic family which preceded the later FLIP CHIPs.

[1] They connect to the units they are plugged into via a set of 22 gold-plated discrete pins along one edge.

They are provided with design advice which includes loading rules and wiring instructions.

[3] They were available in several compatible speed lines: In addition, special modules were available for purposes such as Input/Output (I/O) converters (to standard internal voltages), bus drivers, lamp and solenoid drivers, A/D conversion, relays, core memory drivers, etc.

[8] Larger assemblies which are part of the same family provide core memory testing devices.