5 Nov
2016
5 Nov
'16
8:09 a.m.
It appears that there's a DIP shunt block on
the CPU board where each shunt
corespond to a row of DRAMs. You should check all 4 positions are shorted.
According to the technical manual:
www.bitsavers.org/pdf/sage/sageandstride/Technical_Manual-1983.pdf
they should all be open. I think that
the power-on test checks the first 128K RAM, then sees if the top
location (? first location) of the next 128K works if so, it tests that RAM, and
repeats 128K at a time to work out how much RAM it has. So you may have
defective RAMs in the second 128K.
Also, the manual write it would tell me, if the test fails with the
location of the bad Address. But it say 128K, and just boots ...