Z180 Mark IV


The Z180 Mark IV is a single board computer, meaning it may run stand-alone. It also has an interface to the RetroBrew bus (ECB) for access to additional peripheral boards.



  1. A Z180 cpu up to 33Mhz. Using an 18.432Mhz oscillator, the newest Z180 processors are easily overclocked 2X to 36.864Mhz.
  2. 512k of static RAM memory. Up to 1Mb of EPROM, or up to 512k FLASH memory.
  3. Date/time clock with battery backed NVRAM (DS1302). Backup power is usually provided by a 0.22F super-capacitor.
  4. Terminal connection through an RS-232 port using an IBM-PC serial port 10-pin header.
  5. Twisted pair FDX communication through an RJ-12 (6P4C) modular jack.
  6. A Secure Digital (SD) card slot. Standard, HC, and XC cards are supported by ROM firmware.
  7. A 40-pin IDE connector which supports 8-bit transfers, and is usually used with a Compact Flash card Master/Slave adapter.

Power is supplied to the Mark IV SBC through the ECB bus, or through a 4-pin Molex connector (PC/AT disk drive power connection). The board operates using +5V power only.

Board Archive pages here.


Schematic: :boards:sbc:z180_mark_iv:markiv-sch-2.0-008-rev.pdf

PCB Layout: :boards:sbc:z180_mark_iv:markiv-brd-2.0-008.pdf

Parts List: :boards:sbc:z180_mark_iv:mark_iv-parts_list-2.0-008-rev.txt

Gerber (MFG)::boards:sbc:z180_mark_iv:markiv-2.0-008a-mfg.zip

OBSOLETE: Gerber :boards:sbc:z180_mark_iv:markiv-2.0-008-mfg.zip (out of date Silkscreen layer)

The circuit layers of the two Gerber ZIPs are identical. The “008a” Gerbers correct information on the Silkscreen layer)

Note: For board manufacture at JLPCB rename the PCB_Edges, Inner2, Inner3 file from .gbr to .gm1, .gp1 and .gp2 respectively.


Install SD card socket before installing RR2 so solder pads are more accessible.

Note C40 is installed inside of the socket. Ensure socket has appropriate clearance or install C40 on rear of board.

ROM images

The UNA BIOS was developed on the Mark IV, and was updated to version 2.1 in January 2017. The distributed images contain Will's port of CP/M 2.2.

See: software/ firmwareos / una / binaries for the binary (.tgz and .zip) and source files.

Wayne's RomWBW is also distributed for this board.

boards/sbc/z180_mark_iv/z180_mark_iv.txt · Last modified: 2019/03/16 00:47 by b1ackmai1er
Driven by DokuWiki Recent changes RSS feed Valid CSS Valid XHTML 1.0