26 Aug
2014
26 Aug
'14
4:52 p.m.
On 2014-Aug-26, at 3:14 PM, Eric Smith wrote:
On Tue, Aug 26, 2014 at 3:38 PM, Brent Hilpert
<hilpert at cs.ubc.ca> wrote:
I've been using the "Schematics accompanying Theory Of Operation Manual"
from Dunfield's site:
http://www.classiccmp.org/dunfield/altair/altair6.htm
http://www.classiccmp.org/dunfield/altair/d/88schema.pdf
The CPU / 1K mem / front panel / power supply are all in there.
(I was mistaken, it's the 1K board not 4K.)
While the title suggests it might be simplified schematics, it doesn't appear to be
so, they seem to be complete and as fully detailed as could be expected, perhaps just
presented in some different manner or order than whatever the 'masters' may have
been.
It appears we may be rediscovering what was probably a commonly known issue amongst Altair
owners in 1977.
If this pans out as it appears, one possibility for dr may be to modify a mem board to
ignore DBIN, but I'm getting a little ahead of things.
The Altair 4K mem board schematic indicates it
puts data on the bus when the board is addressed and MEMR asserted. It appears to ignore
DBIN.
Is that schematic online? My cursory search turned up only a copy of
the manual without schematic.