Extended UNIBUS memories

Extended UNIBUS memory main memory cards were available from DEC and from a number of outside vendors.

All DEC EUB memory used DRAMs, and used ECC to automagically correct single-bit errors, and (at a slight penalty in response time when an error occurs) detect double-bit errors.

DEC

• MS11-L MOS memory - primarily UNIBUS, but had an EUB mode
• MS11-M MOS memory - MS11-MA, -MB models (128, 256 Kbytes)
• MS11-P MOS memory - (1 Mbytes)