SRAM memory map

The TBBlue firmware maps the SRAM(s) as follows:

0x000000 – 0x00FFFF (64K) => ZX Spectrum ROM
0x010000 – 0x013FFF (16K) => ESXDOS ROM
0x014000 – 0x017FFF (16K) => Multiface ROM
0x018000 – 0x01BFFF (16K) => Multiface extra ROM
0x01c000 – 0x01FFFF (16K) => Multiface RAM
0x020000 – 0x03FFFF (128K) => divMMC RAM
0x040000 – 0x05FFFF (128K) => ZX Spectrum RAM
0x060000 – 0x07FFFF (128K) => Extra RAM

0x080000 – 0x0FFFFF (512K) => 1st Extra IC RAM (if present)
0x100000 – 0x17FFFF (512K) => 2nd Extra IC RAM (if present)
0x180000 – 0xFFFFFF (512K) => 3rd Extra IC RAM (if present)