Table of Contents
System Verification and Troubleshooting
Table 3-2. Maintenance Panel Switches and Lamps (Continued)
-----r---------------r-----------------------------------------
Panel I Panel Marking I
Use
Row I
I
----,-----------_._---,-----------------------------------------
3
3
ENABLE 0
through 4
( lamps)
CBI4, CB 15
( lamps)
Display the module enable lines.
Each
line is associated with a like numbered
module and, when true, indicates a mod-
ule is transferring data.
The enable
lines are monitored by the modules to
resol ve pr ior it ies.
Display MSBs of address ,on CTL-Bus.
3
I/O LORQ
(lamp)
3
I/O HIRQ
( lamp)
3
I/O SELECT
( lamp)
Ind ica tes the lOP is issuing a low pri-
,
ority request for use of the CTL-Bus.
I
I
Indica tes the lOP is issuing a high pri-I
or i ty request for use of the CTL -Bus.
I
I
Indica tes the lOP is selected to use the
CTL -Bus.
4
4
4
4
4
4
4
FLAG 1, FLAG 2
FLAG 3 (lamps)
TNAME 0, TNAME
I (lamp s)
SKIP (lamp)
NOP 2 (lamp)
REPEAT (lamp)
ALU CARRY
(lamp)
ALU OVFL
(lamp)
Indicate the states of the three Flag
flip-flops controlled primarily by the
Special Field microinstructions.
Ind ica te the s ta tes of the TOS name r
bits.
These bits specify the mapping
between the TOS registers RA, RB, RC,
RD, and the associated physical regist-
ers.
Indicates a skip condition is met during
the current clock cycle.
Indicates the state of the NOP 2 bit.
When tr ue, causes a "no operation
II
by
Rank 2 of the ROM Output Register.
Indicates the Repeat bit is true, caus-
ing the microporcessor to repea t the
current microinstruction until the skip
condition is met.
Indicates the carry signal from the
microprocessor ALU is true.
Indicates the overflow signal from the
microprocessor is true.
3-8
Chapters
Table of Contents
Troubleshooting
