Z100 Lifeline - IDE Controller Board
This board was an answer to the wide verity of IDE hard disks that became cheap
and abundant in year 2000 and beyond.
The board was designed an put together by a group of
guys that have worked together as a user group with the Heath/Zenith
Z-100 system that go under the
name Z100-Lifeline. They are still active and can be contacted
The Z100 IDE Interface is a multifunction S-100
board designed for the Heath/Zenith Z-100 Series computer but in reality could
be used with most S-100 systems. It provides the following features:-
An interface from the Z-100 S-100 computer bus to the industry standard IDE hard
drive interface. This allows you to connect up to four standard IDE drives which
are much more available than the old MFM hard drives originally supported S-100
HD Controller boards. DMA capabilities, however, are not supported. Solid state
memory devices, such as compact flash cards, that use the IDE interface can also
The circuit design utilizes a complex programmable logic device (CPLD) from
Altera for all of the control circuitry. This programmable device was chosen
because it made development easier and hopefully more reliable. It also required
less power. Altera was chosen because the development tools were readily
available from their web site.
Non-Volatile Static RAM
A bootable Non-Volatile Static RAM (NVsRAM) device is also present. This
nonvolatile memory storage device, based on the Texas Instruments bq4850
programmable NVsRAM, can be programmed at any time without removing it from the
board. The NVsRAM device is fully bootable and can contain up to 512k of user
selectable programs or files, making it an excellent choice for holding the CPM
or DOS boot up files. The bq4850 has an onboard real time clock and an internal
battery for memory retention. There are no special programming voltage required
so programming is greatly simplified with no special timing routines required.
A breakout switch to enable program analysis using the Z-100's enhanced Monitor
ROM utilities from the hand prompt or the DEBUG utility.
A prototype area for adding your own options. One idea is to add a second NVsRAM
chip selected by means of a toggle switch.
The board has two IDE 40 pin connectors allowing up to 4 IDE drives to be
connected. The S-100 bus (pre -IEEE-696) is an 8 bit data bus. The IDE is
16 bits wide. The onboard Aktera converts the odd/even data to 16
bits for transfer to the IDE drive.
There is a large amount of documentation for this board at the Lifelines Web
site. See here.
A description of the board can be obtained
The schematic for this board can be obtained
A description of how the Altera CPLD was programmed can be obtained
An example of a BIOS for PC-DOC can be obtained
I intend to write a CPM driver for this very useful board in the future. If
anybody is interested please see
the following useful pieces of information.
Connecting to IDE Drives and
Basics of an IDE Interface
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