32KB SRAM Expansion

MIRE contains 32KB of SRAM which is mapped to TRS-80 memory range 0x8000-0xFFFF, just like a fully-configured original Expansion Interface's DRAM.

Some TRS-80 Model I keyboard units have internal RAM expansion kits installed, such as the vintage Holmes Engineering IM-1B and IM-2 products. These will conflict with the MISE's SRAM unless one these two procedures is followed:

  1. Disable the keyboard memory expansion kit, or
  2. Switch the MIRE DIP switch labeled "1" to the ON position. This disables the MIRE's SRAM.
If you're not sure whether your keyboard unit has a memory expansion installed, simply turn on DIP switch 1 and use your DOS's command (MEMORY or similar) to see whether more than 16KB is present.

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