146

1945 28 Dec 67
In chasing the elusive "parity
error in core 3 only when disk
is runnning" bug & discovered that
when the 6684 + 10B margins on core 3
are 1½ V low it causes parity
errors for the 167 at 40500 and
other such. -- In core 0! ??
SRR

2000 28 Dec 67
System back to users. The "Disk
causes parity error in another part of core 3"
(+1 ereinafter refered to as the DCPEIAPOC3) bug
but is independent of the +10B margins
on core 3 and of the balun board in
1 K5 in core three. This balun board
could have had open resettors
to cause the good old percolate bug to
reappear. (Maybe). When the clock
service routine has a lot of SKIP 533's
in it, it reduces the probability of
533 getting clobbered. Without those instructions
the probability of 533 getting clobbered
is much higher.
SRR

Order of Mem Reffs by CP is
all res

Core 133R/W 0123 03R/W the list core 0
is the SKIPL and the last 3 is
the parity error
SRR