Table 4-1. Controls and Indicators (Cont'd)

T.O. 31S5-4-308-1

TM 11-5805-663-14-13

NAVELEX 0967-464-0010

FUNCTION

TYPE

NAME

can appear to be on simultaneously when the run

run

and halt conditions are interlaced at a high repetition

(Cont'd)

rate. When this occurs the halt indicator could

be less intense than the runindicator because the

halt has a minimum delay time of 0.1 second.

The indicator is on when the CPU is waiting for

Indicator

idle

an external interrupt.

Touching the switch forces the CPU to stop executing

Touch response

halt

instructions, as long as the done indicator remains

indicator switch

on. After the CPU has halted program execution,

the indicator is on.

When indicator is on, and when the address on the

Touch response

adh

INFIBUS compares exactly to the address switch in-

indicator switch

dicators, the CPU is halted as long as the done

indicator remains on. When the indicator is on,

the switch is ineffective during the time the Program

Maintenance Panel is the master accesssing the

INFIBUS. The switch-indicator has toggle action.

Touching the switch turns on its indicator and causes

Touch response

step

the CPU to execute the next instruction. At the

indicator switch

completion of this instruction the contents of the CPU

indicators. The done indicator must remain on fol-

l o w i n g this action.

Touch response

This switch differs from all the others because it

atten

indicator switch

does not actuate until the touch is released. The

indicator appears to remain off if the CPU imme-

diately service the attention interrupt. However,

if the CPU was not interrupted upon the release

of the switch, then the indicator is on and the

Program Maintenance Panel is locked up until the

interrupt occurs. This condition occurs:

a . If the CPU was halted.

b. If the inh indicator has been on prior

to releasing the switch.

C. If the CPU is operating with all interrupts

inhibited.

The switch can always be toggled off by touching

and releasing it for a second time, thereby unlocking

the Program Maintenance Panel.

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