Rockwell Automation 1785-Lxxx Enhanced and Ethernet PLC-5 Programmable Controllers - Manual (Page 304)

Publication 1785-UM012D-EN-P - July 2005
D-4 Instruction Set Quick Reference
Counter Instructions
Instruction Description
Retentive Timer On
RTO
Status Bits:
EN - Enable
TT - Timer Timing
DN - Done
Timer Reset
RES If the input conditions go true, timer T4:1 is reset. This
instruction resets timers and counters, as well as control
blocks. This is necessary to reset the RTO accumulated value.
RTO
RETENTIVE TIMER ON
Timer
Preset
T4:10
10
1.0
0
Time Base
Accum
If the input conditions go true, timer T4:10 starts incrementing i
1-second intervals as long as the rung remains true. When the
rung goes false, the timer stops. If the rung goes true again, th
timer continues. When the accumulated value is greater than o
equal to the preset (10), the timer stops and sets the timer don
bit.
Rung
Condition
EN
15
TT
14
DN
13
ACC
Value
RTO
Status
False
True
False
0
1
0
0
1
0
0
0
0
0
increase
maintains
Disabled
Timing
Disabled
True 1 0 1 >= preset Done
T4:1
( ) RES
Instruction Description
Count Up
CTU
Status Bits:
CU-Count Up
CD-Count Down
DN-Count Up done
OV-Overflow
UN-Underflow
CTU
COUNT UP
Counter
Preset
C5:1
10
0 Accum
If the input conditions go true, counter C5:1 starts counting,
incrementing by 1 every time the rung goes from
false-to-true. When the accumulated value is greater than or
equal to the preset value (10), the counter sets the counter
Rung
Condition
CU
15
DN
13
OV
12
ACC
Value
CTU
Status
False
Toggle True
True
0
1
1
0
0
1
0
0
0
0
incr by 1
>= preset
Disabled
Counting
Done
True 1 1 1 >32767 Overflow
See page F-8 for a description of prescan operation for
this instruction.