IBM System/360 2050

Maintenance
Operation
Error Logout
Normal Syst.-n / 360
Operation
ROS Mode
l.
2.
l.
2.
3.
l,
' 2.
Maintenance Operation
Normal Systf!m/360 Op .. rotion
Sequence Counter Mode
FLT load
Logout:
a.
Error
b. Logout Pushbutton
Main Store Mode
Main Store Mode FL T's
..,p.,.__~4';;.. Logout
-
L·""'t
Main Store Ripple Test
ROS Mode
ROS Kernels (Maintenance
l.
AH System/ 360 Instructions
Routines)·
2.
I - Fetch of Diagnm.e Instruction
a. ROS Mode F LT's
b. AH Logouts or Scan-Ou~
c, Execution of Diagnose
Instruction
Diagnostics
FIGURE 6. BASIC OPERATIONS AND CPU CONTROL MODES
Sequence
Counter
Mode
Entered via: Obiectives Control or Instruction Source
f---·--------------------+-------------"-----·-------+--· __ " _____ " ______ __,
I
I. FLT mode sw on "Sturt-Lood" 1 or 2. Read FLT mode tapes or disks into Controlled directly by sequence stats and
and Load PB storage: "OR 's
11
each pair sequence counter.
2. Coll for FLT load: (odd/even) of consecutive words on
a. MS mode -- op code A tape or disk including parity bit
b. ROS mode -- scan*E, 00 generation, into each storage
and Em;t 1010 location used.
3. Logout PB 3 or 4. Logout into storage:
4. Initiation of error log a. SOR to location 80
b, SAR on;J byte stats to location 84
c. I AR to locoti on 88
f-.---------~-r-- Entered._v_;o_._·_ ------------~~-~-~--~~-'-~~~~~~~o __ b_i_e __ c_ti_v_e_s~~~~~~~-~~~~-C_o_n_r_ro_l_o_r~ln_s_tr_u_c_ti_o_n~So_u_r_c_e~~~~~~-i
l. Call for MS mode while in Seq lo. MS hardcore tests end ROS bit tests 1. FLT op register: Decodes pority bits of
Ctr mode: or ROS ripple test. word in SDR.
Main
Store
Mode
ROS
Mode
o. During FLT lood lb. Logout into storage:
b. Logout (o) ROSDR (groups 1 -4). This is
2, Main store ripple test: one ROS word (0-89) which is
Storage test sw off Process, sent to storage locations SC,
and Start PB. 90, 94, and 98.
NOTE: The MS ripple test must run
correctly before trying FLT's.
Entered via:
1. Call for ROS mode while in
MS mode:
a. Performing Fl T's
b. Logout
2.
Start PB, then system reset PB.
2.
lo.
lb.
2.
(b) ROAR to location 9C.
Test main storage via ripple
( l 1s, 0
1
s, worst, and reverse worst)
Objectives
ROS hardcore tests and zero and
ane cycle tests.
Logout into storage:
CPU and/or channel status.
Progressive scan of channels,
Special maintenance routines
(kernels) in ROS.
FIGURE 7. CPU CONTROL MODES FOR MAINTENANCE OPERATIONS
2. Storage test switch: Setting determines test.
Control or Instruction Source
1. FLT Op register: Decodes emit field bits
(under microprogram control).
2. Microprogram control and linkage control
words (LCW's).
Maintenance Features (3/71) 19