SRAM memory map

The Spectrum Next standard boards with 1024K SRAM are mapped 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 – 0x05FFFF (256K) => divMMC RAM
0x060000 – 0x07FFFF (128K) => ZX Spectrum RAM
0x080000 – 0x0FFFFF (512K) => Extra RAM

TBBlue’s standard PCBs with 512K SRAM are mapped as follows:
(Next devkits prior to Issue 2, VTrucco, FBlabs, DE-1, DE-2, Multicore, WXEDA, ZX-Uno)

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