Z-One

http://www.nomad.ee/micros/z-one/

• Z80 running at up to 4.6Mhz, changeable in MCU firmware
• Memory address space filled with 64K RAM
• CP/M running, with maxed out storage on SD card (16x8MB drives). You need at least 256MB card.
• ATMega1284P as system controller:
  • Provides system clock for Z80
  • Contains and serves bootloader, monitor, and CP/M binaries
  • At startup, patches Z80 bootloader into first 128 bytes of RAM
  • SD card interface and initialization
  • Console port for Z80-ChibiTerm connection, using UART at 115200
  • Heathkit H19 terminal emulation, with special keymappings for WordStar
  • Software implemented auxiliary serial port connected to FTDI based USB-Serial converter, up to 19200
  • Interval timer with 10ms resolution
• Integrated ChibiTerm
  • 80×30 character text with analog VGA connector
  • Inverse text and line drawing characters
  • PS/2 keyboard, US layout only
• Boots into system monitor if no SD card, that has
  • Commands to examine and change memory
  • Built in Z80 disassembler
  • SD card read/write sector commands
  • Can read/write I/O ports
  • Can run code, examine registers
  • Download Intel Hex file from auxiliary port
• Wait logic for adding 2nd MCU
• Runs from 5V, with modern CMOS Z80 and HCT series logic chips uses less than 70mA

Z-Two

http://www.nomad.ee/micros/z-two/

Like Z-One, but without physical Z80.

• ATMega1284P, running at 18.432MHz is the brains of the operation
• Emulates Z80
  • All documented Z80 instruction set, at about 110000 instructions/sec at 18.482MHz ATMega clock
  • Enough undocumented ones to pass all Frank Cringle's yaze tests
  • Does not emulate undocumented flags 5 and 3
  • No external interrupt capabilities
• Can physically address all 512K of memory, although currently only uses 64K for Z80 emulator
• Contains and provides boot loader, monitor, and CP/M binaries
• SD card interface and initialization
• Console port for Z80-ChibiTerm connection, using UART at 115200
• Heathkit H19 terminal emulation, with special key mappings for WordStar
• Auxiliary serial port connected to FTDI based USB-Serial converter
• SD card interface and initialization
• Provides interval timer with 10ms resolution
• CP/M 2.2 running, with maxed out storage on SD card (16x8MB drives). You need at least 256MB card.
• Integrated ChibiTerm
• The whole system runs from 3.3V, regulated down from 5V supply voltage. Uses less than 10mA

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