/* Imported from Wayback Machine Original URL : https://www.retrobrewcomputers.org/doku.php?id=builderpages:plasmo:z80mb64:memmap Snapshot date: 2023-05-29 Generator : wayback-archiver */ ==== Table of Contents ==== [[#z80mb64_and_z80sbc64_memory_i_o_map|Z80MB64 and Z80SBC64 Memory, I/O map]] [[#memory_map|Memory Map]] [[#i_o_map|I/O Map]] [[#uart|UART]] [[#compact_flash_registers|Compact Flash Registers]] [[#bank_select_register|Bank Select Register]] ====== Z80MB64 and Z80SBC64 Memory, I/O map ====== ===== Memory Map ===== The memory is consists of 128K of RAM in four 32-K banks: Top 32K of RAM is the common memory. The bottom 32K can be bank selected by writing to bank select register at I/O location 0x1F as follow: 0x0 is normal operation 0x1 do not use 0x2 is for bank 0 of CP/M-3 0x3 is the reset value where the top 32K of physical memory is mapped to 0x0-0x7FFF ===== I/O Map ===== ==== UART ==== A hardware receiver is implemented in CPLD with the following I/O addresses: Read-only serial data receive register at 0xF9 Read-only serial receive status register at 0xF8 where D[0] is the receive ready flag, 1 indicates data is ready, 0 indicates no data Write-only bit-bang transmit register at 0xF9 The content of D[0] appears on the TX output pin. D[0] is high at reset. Software must “bit-bang” D[0] of transmit register to emulate the serial port transmit function. ==== Compact Flash Registers ==== Compact flash registers are 0x10 to 0x17 ==== Bank Select Register ==== Bank select register is write only located at 0x1F