IBM 5280 Manual page 240

COMMUNICATIONS MAP
MAP 3015-2
COMM PROBLEMS
PAGE 2 OF 4
(Step 001 continued)
Have the customer maintain a record of the communications error log
and the internal data trap by calling 'TCOMLOG' after his program
ends in an abnormal termination.
Use the program 'TCOMEREP' to display and print the error logs
recorded by 'TCOMLOG'.
Work with the customer to verify that the communications
configuration record is correct. This may require knowing what the
DCR name is and using the program 'SYSCCU' to look at the
configuration record.
Verify that all jumpers, strapping, and cable hook ups are correct
for the communications feature and modems being used.
(See MIM for strapping information.)
Verify that all lines from the coupler have continuity through the
cables, the communications MPU card, the logic board, and to the
feature card (38LS, EIA, or DDSA).
(See MIM for cable routing and pin information.)
For line problems:
*
Use the TRAP or PT-2 to make recordings of activity for later
analysis.
*
Use the internal trap save program 'TCOMLOG'
and received at the communications. MPU card.
to save data sent
For BSC communications access method:
*
Use the BSC on line test to verify BSC operation of the line.
For SDLC communications access method:
*
Have a host system run an
SNA SDLe
test on your system (thlS test
is transparrent to your system and may be run when SNA is active).
If there is an external IBM modem, use the tests provided by that modem.
Marginal voltages cause intermittent problems. Check all voltages
for nominal values. Check for excessive ripple in the DC supplies.
Check common ground continuity between the machine and the telephone
company interface.
Vibrate the machine to show up loose connections.
Heat and cool the machine to show up temperature sensitivity.
Is the
diagnostic
condition?
Y N
3 3
A B
communications
routine in a
MDI
hang
EC840874 PEC839787
MAP 3015-2