User guide

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H8 HARDWARE INSTALLATION
The only board presently available to support any hard disk on the H8 is the Heath WH8 -37 card.
This card contains both a 5" soft sector H37 compatible floppy controller interface, and a
standard SASI interface bus. Since this card has both interfaces built in, and CP/M only supports
two devices, I assume the majority of users will only have this card installed - not the H47 or H17.
To use this interface card with the H8 computer, a Z80 CPU must be used. Any Z80 should work - since
I have used the Trionyx Z80 card and the Heath Z80 card, and my H8 systems are up and running
with these cards, I am in the position to support the Heath and Trionyx Z80 CPU cards. We know
from past experience that the DG system also works, and I have some information on this if
needed. I will try to support all configurations, but since I do not have them, it may be difficult.
The only difference should be because of different monitor ROMs used. With the WH837 card you
also get the PAM-37 PAnel Monitor ROM set, which should be installed on the CPU you are using.
Disregard the CPU board manufacturer’s instructions for CPU status switch settings and follow the
PAM-37 documentation instead. NOTE: The Trionyx CPU card status switch SW3 is equivalent to
the Heath CPU port status switch with a few exceptions. 1) Heath labels their switch 0 through 7,
while Trionyx labels theirs 1 through 8. Thus Heath's 0 position correspond to Trionyx's 1
position, etc. Also Heath's switch ON (1) and OFF (0) is opposite Trionyx switch labeling.
Therefore if the PAM-37 documentation says set the Heath CPU positions 0 and 1 to 00, you
would set Trionyx 1 and 2 to 11, etc.
Follow all preparation and installation instructions in th e Heath instruction manual for the Z-67
interface, WH-8-37. For the H8 you must set all dip switch positions on the WH -8-37 card to the
left position in order to get the BOOT partition table when BOOTing your system. Follow the
included PAM-37 documentation for setting your switch settings for default ports and port
assignments. Also, if a Z80 CPU other than the Heath Z80 CPU is being used, check that it is
properly set up and configured according to the Z80 vendor's settings (except for the PAM -37
monitor ROM). If in doubt, call the vendor.
Since the H8 is capable of universal boot without worrying about the switch settings on the CPU,
you may want to use the universal boot routine to boot off the Winchester or any floppy drives
you are using. Refer to the ROM manual on how to accomplish this. For those interested in
having multiple controller cards in the H8 at one time (I have the H17, H37, H67 installed and can
switch them in and out without having to ever take the H8 cover off), refer to my article in
H-SCOOP issue #56 (November '84). It is possible, for example, to have one CP/M and/or HDOS
partition set up for H37/winnie and another for H17/winnie. All sorts of neat tricks are then
possible for file transfer and conversion.
Please note that if the H17 card is being used, it must be set to port 7C (174Q), and the SASI
(Z67) must be set to 78C (170Q). If you have the H37 card only, the Z67 interface (SW3 on the
CPU card) must be set at "1 0" on the CPU switch (port 174Q, 7CH), and the Z37 interface
portion must be set at "0 0" on the CPU switch (port 170Q, 78H), as outlined in the PAM -37
manual. You will also need to set the default BOOT device per PAM-37 instructions (SW3 on CPU