Main Storage Ripple Test - IBM System/360 2050 Maintenance Manual

Processing unit
Table of Contents

Advertisement

Bypass tests unti I this
net is not
listed
as an entry.
If no failures like this appear,
return to original stop and
refer to logic for repair.
(Scan-in foilure--hardcore
QY310)
No
Yes
Yes
No
If this is error reg or if these
triggers hove lotch-bock
paths, ignore this entry and
scope other
G/F
entries.
Refer to logic and repair or
bypass test (s) unti I output
point is not en entry.
Fig 34
~
If much trouble is encountered on a particulor failure, make note of it
and continue
on
to the following tests in on attempt to find on easier
failure to troubleshoot.
FIGURE 35.
CYCLE TEST REPAIR PROCEDURE
Main Storage Ripple Test
Following is the procedure for running the main stor-
age ripple test:
1.
Set the storage test rotary switch to the zeros
position.
2. Press the write lever switch.
3. Press the start key. IAR and SAR indicators
15 *through 29 should blink and SDR should contain ones.
4. Return the write lever switch to the neutral
position.
56
(3/71)
Model SO FF.MM
Yes
Suspect:
input
or
o clock
pulse is gated
during I agout
The foi lure is
between the good
ne
15
and the bod
net
Determine nets
feeding the bod
G/F
net
No
Suspect:
logout or
compare and
branch
No
Determine nets
feeding the
AA
net
Detemiine nets
J
feeding this bod
~net
- ·
5. Press stop on check. IAR and SAR indicators
15* through 29 should blink and SDR should contain
zeros. Return stop on check switch to normal.
6. Repeat steps 2-5 with the rotary switch set
to the ones position. Indications should be the same
except SDR should contain all ones at step 5.
~
While running the ones test, set the storage
test switch to the process position. This gates the
storage parity bits to the FLT op reg (2-5) thus
turning the binary trigger on and off.
7. Repair any failures before continuing.
8. Return the main storage test controls to normal.
*
Depends on storage size; 15 equ:i.ls 128K.

Advertisement

Table of Contents
loading

Table of Contents