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Description: efi68k
============
CPU: MC68HC000 @16MHz
RAM: 256k
ROM: 256k

   Based upon a 16MHz 68HC000, efi332 is a minimally configured 4x6
inch single board computer. It includes the following major
components: (a) 256k SRAM (km681000l), (b) 256 EPROM (27C010), 
(c) DP8570A (clock/timer/calendar), (d) MAX791 (cpu supervisory chip
with battery backup switch-over and watch dog timer), and 
(e) NS16550DN (UART). The following interrupt functions have also been
incorporated: UART, TIMER, Watch Dog, and Low Line voltage (trips at
4.85V; enough time to save the cpu reg before reset is asserted on
power down).
   The schematic for efi68k is freely available via e-mail. Send
"index diy_efi" to majordomo@coulomb.eng.ohio-state.edu. Retrieve the
files related to 68hc000-1.00 with the "get diy_efi <filename>"
command. efi68k does not have an available printed circuit board, but
can be wire-wrapped in about four days. Cost is about $100US.

TODO:
=====
- add the "tm27 vector" ... can we use a trap instruction?
- generate include/coverhd.c to perform the tmtest.
- the interrupt drive I/O should be integrated into the RTEMS.
- finish the ROM memory model.
- add separate interrupt stack (low priority).

                                       John S Gwynne
                                          Gwynne.1@osu.edu
_______________________________________________________________________________
               T h e   O h i o - S t a t e   U n i v e r s i t y
    ElectroScience Laboratory, 1320 Kinnear Road, Columbus, Ohio 43212, USA
                Telephone: (614) 292-7981 * Fax: (614) 292-7297
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