DL205 User Manual, 4th Edition, Rev. B
5–48
Chapter 5: Standard RLL Instructions - Timer, Counter and Shift Register
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Stage Counter (SGCNT)
The Stage Counter is a single-input counter that
increments when the input logic transitions from off to
on. This counter differs from other counters since it will
hold its current value until reset using the RST
instruction. The Stage Counter is designed for use in
RLL
PLUS
programs but can be used in relay ladder logic
programs. When the current value equals the preset
value, the counter status bit turns on and the counter
continues to count up to a maximum count of 9999. The
maximum value will be held until the counter is reset.
Instruction Specifications
Counter Reference
(CTaaa): Specifies the counter number.
Preset Value
(Bbbb): Constant value (K) or a V-memory location.(Pointer (P) for DL240,
DL250-1 and DL260.)
Current Values:
Counter current values are accessed by referencing the associated V or CT
memory locations*. The V-memory location is the counter lo 1000. For example, the
counter current value for CT3 resides in V-memory location V1003.
Discrete Status Bit
: The discrete status bit is accessed by referencing the associated CT
memory location. It will be on if the value is equal to or greater than the preset value. For
example, the discrete status bit for Counter 2 would be CT2.
NOTE:
When using a counter inside a stage, the stage must be active for one scan before the input to the
counter makes a 0-1 transition. Otherwise, there is no real transition and the counter will not count.
NOTE:
A V-memory preset is required only if the ladder program or an OIT must used to change the preset.
NOTE: *
Both the Counter discrete status bits and the current value are accessed with the same data
reference with the HPP.
Direct
SOFT uses separate references, such as “CT2” for discrete status bit for
Counter CT2, and “CTA2” for the current value of Counter CT2.
CT aaa
SGCNT
B bbb
Preset
Counter #
Operand Data
Type
DL230 Range
DL240 Range
DL250-1 Range
DL260 Range
B
aaa
bbb
aaa
bbb
aaa
bbb
aaa
bbb
Counters CT
0-77
0-177
0-177
0-377
V-memory for
preset values V
–
2000-2377
–
2000-3777
–
1400-7377
10000-17777
–
1400-7377
10000-37777
Pointers
(presets only) P
2000-3777
1400-7377
10000-17777
1400-7377
10000-37777
Constants
(presets only) K
–
0-9999
–
0-9999
–
0-9999
–
0-9999
Counter discrete
status bits CT/V
0-77 or V41140-41143
0-177 or V41140-41147
0-177 or V41140-41147
0-377 or V41140-41157
Counter current
values V/CT
1000-1077
1000-1177
1000-1177
1000-1377
The counter discrete status bit and the
current value are not specified in the
counter instruction.
þ
þ
þ
þ
230
240
250-1
260
DS
Used
HPP Used