wiki:Z80Laptop

Dreaming of a CP/M Z80 laptop!

Evolving Design

  • Z80 CPU, DART, PIO
  • AT28C256 32Kx8 EEPROM
  • AS6C4008 512Kx8 SRAM
  • Clocks: 8MHz osc /2 => 4MHz CPU clock
  • Clocks: 1.8432MHz / 12 => 16X 9600 clock
  • MAX232 or equiv; DB-25 for RS-232

Other

  • Cherry G84 keyboard?
    • 11 x 5.2 x 1 in USB
  • NEC NL6448AC33-18 display (9.6 x 7.3 in 640x480 VGA timing) data
    • Mating connector Hirose H123172-ND (IDC)
    • Cable AE34A-5-ND
    • Other end WM14334-ND mated to WM6581-ND

Lots of NVRAM / flash and RAM disk

Parts:

  • 128Kx8 flash: GLS29EE010-70-4C-PHE
  • 32Kx8 flash: AT28C256-15PU
  • 512Kx8 SRAM: AS6C4008-55PCN
  • 128Kx8 SRAM: AS6C1008-55PCN
  • Z80 8MHz CPU: Z84C0008PEG
  • Serial I/O:
    • SCN2661 / SCN 68661 EPCI (single port w/ baud rate gen)
    • XR886681 or SCC2681 (progr. baud rate but hard to find)
    • Z80 DART: Z8470 (needs baud rate) or SIO same deal

Floppy controllers:

  • FD1797 (needs data separator) sample schem
  • WD2797 (on-chip PLL data separator)
  • WD37C65C (NEC 765 clone?)
  • FDC9266
  • WD1770/1771/1772 (5-1/4 inch drives only?)

Thinking about making an Osh Park test board with WD2797 and 8" and 5" floppy connectors. Could have an ATMega or Xilix eval board interface. Possibly RC2014 compliant, need to study their bus.

Software:

  • FDU disk utility supports amongst other things formatting of 8" floppies

Emulators:

Design ideas:

  • In 13x9 inch box, keyboard and PCB ~ 12 x 2.8 would fit.
  • Need a terminal emulator to generate VGA timing and deal with USB/PS-2 keyboard.
Last modified 3 weeks ago Last modified on Oct 31, 2019, 11:19:05 AM