User guide

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CABLE ORIENTATION The ribbon cable used for the disk drives and our hard disk unit must be
plugged into the controller card in the proper direction. For the H89 systems, pin 1 is always up.
For the H8 pin 1 is always to the left. The pin 1 position of the drive cables can b e identified by a
stripe along the ribbon cable edge and/or a dot or mark on the connector.
4MHZ OPERATION The Trionyx H8 CPU board supports both 2 and 4 MHz operation with a simple
jumper change or via software. If you use the jumper method, you will boo t at either 2 or 4 MHz
depending on the jumper. I placed a switch on my H8's left side which is connected to the Trionyx CPU
speed selector whereby throwing the switch up will cause the H8 to boot at 2 MHz, and throwing the
switch down will cause the H8 to boot at 4 MHz. The software provided with your hard disk
system will operate and boot at both 2 and 4 MHz with the proper systems.
For the H89, if you wish to BOOT at 4 MHz, you will require a monitor ROM such as the
UltiMeth MTR-4K or the Kres equivalent. In addition, the CPU board must have been modified to support
4MHz operation. The easiest 4MHz modification to use is booting at 2MHz and switching to 4MHz
after boot. This can easily be accomplished by the Kres 2/4 MHz H89 modification. Prese ntly, the
only technically sound modification on the market as of this writing is the Kres 2/4 MHz board.