26 Aug
2014
26 Aug
'14
12:43 p.m.
On 2014-Aug-26, at 11:59 AM, drlegendre . wrote:
On Tue, Aug 26, 2014 at 1:10 PM, Brent Hilpert
<hilpert at cs.ubc.ca> wrote:
.. this crossed over with a message I just sent which addresses some of this.
OK, what is the manufacturer/model of the DRAM board? Need to sort out the bank addressing
and the phantom function for the board, as well as the following issue.
A niggling question I have in the back of my head, is whether or not some/many memory
boards will work with the Altair front panel.
As stated in my previous message the front panel expects a memory board to be putting data
onto the DI bus to be observable on the LEDs when idle, the front panel does not latch the
data from a last memory cycle.
I suspect many memory boards don't do this, they may only put (strobe) data onto the
bus during the active portion of a memory cycle. The bus lines would then revert to the
high state and all you would see is ON LEDs.
Yes, arguably it's too bad you don't have a small static-RAM board as they tend to
be electronically simpler.
On the other hand such boards are also earlier and may be less reliable than a late model
DRAM board.
Do you mean to say you have a memory board
installed, or just that the
address lights are at times stable and will increment-by-one when
examine-next is pressed?
Both, actually. All I have for memory is this 64K DRAM card, and I've been
experimenting with it both in and out of the system. But since the data
LEDs are always solid on, I have no way of telling whether or not I can
actually deposit or examine a location.
Next I'll pull the power for the term. stuff and see how it acts. It's a
tough spot to be in, too many variables and unknowns.. not sure what I can
or can't trust. So I just have to keep pecking away one bit at a time.