28 Aug
2002
28 Aug
'02
9:31 p.m.
Thanks Jeff,
Yes, these are the switches in the upper left. But knowing that they
are address selection switches does not help much. I presumed they
were. But there appear to be 4 banks of 4K RAM. That should only
require about 4 switches for selection. There are 16 switches
however.
So, if you have the manual, can you say what the specific switch
assignements are?
Also, what is the analog circuitry in the lower right, with the delay
module?
Thanks,
I have a
Processor Tech. 16KRA (16K RAM) board. There are three
components missing on the board.
U40 14 pin DIP
74LS136
U42 16 pin DIP
74LS157
U58 16 pin DIP
74LS157
Anyone know what they are? There are also 2 8-pin
dip switches that
control addressing and who knows what else. Anyone have the switch
description?
Is this in the upper left corner of the board? If so it
controls the page and address line assignments for the address
selection switches.
All of this info came out of the '16KRA Users Manual', forth
printing, April 1978.
Jeff
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