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- Date: 8 Jul 82 1:00:01-PDT (Thu)
- To: info-micro at mit-ai
- From: decvax!harpo!duke!ucf-cs!goldfarb at Berkeley
- Subject: H-8 Upgrades
-
- I have an H-8 with 128K of memory, a Z80A, an S-100 disk controller,
- and some other goodies. It runs CP/M on normal, 8" floppies (Shugart
- 851's). D-G Electronic Developments Co., 1827 S. Armstrong St.,
- Garland, TX. 75020, supplied the CPU, replacement front-panel EPROM,
- and the dynamic RAM. Their prices were quite reasonable, as were their
- designs, enabling the old H-8 to use the Z80A and all 64K of address
- space at 4Mhz. The disk controller is an S-100 type, a Jade Double D
- purchased from Jade Computer Products in California for $60 for the
- bare board. It has an on-board Z80A and uses a WD 179X FDC chip. I
- made an adapter card to create an S-100 bus slot for the H-8. This
- required only two bus buffers and five other IC's, plus a slight mod
- to the memory cards to handle the S-100 PHANTOM* signal. Since the
- Jade controller does not use DMA, no fancy interfacing was necessary.
- With the above configuration plus a Heath 4-port serial card, the old
- H-8 is a reasonable CP/M machine. But don't count on Heath (or anyone
- else's) support for too long: the H-8 is dead!
- Ben Goldfarb
- USENET: ...!duke!ucf-cs!goldfarb
- ARPANET: Goldfarb.ucf-cs @ UDel-Relay
-