418
FX
3U
/FX
3UC
Series Programmable Controllers
Programming Manual - Basic & Applied Instruction Edition
15 External FX I/O Device – FNC 70 to FNC 79
15.6 FNC 75 – ARWS / Arrow Switch
4) Operation of the switches for changing data in each digit (
and
+1)
In a digit specified by a digit selection switch described above, data is changed as follows:
- When the increment input turns ON
Every time the increment switch is pressed, the contents of
change in the way "0
→
1
→
2
→ ...
→
8
→
9
→
0
→
1".
- When the decrement input turns ON
Every time the decrement switch is pressed, the contents of
change in the way "0
→
9
→
8
→
7
... 1
→
0
→
9".
The contents can be displayed in the seven-segment display unit.
As described above, a target numeric value can be written to
using a series of operation while
looking at the seven-segment display unit.
Cautions
1. Setting of the parameter "n"
Refer to the explanation of parameter setting in SEGL (FNC 74) instruction. The setting range is from 0 to 3
for ARWS instruction.
→
For the parameter setting, refer to Subsection 15.5.2.
2. Output type of the PLC
Use a transistor output type PLC.
3. Scan time (operation cycle) and the display timing
ARWS instruction is executed in synchronization with the scan time (operation cycle) of the PLC.
For achieving a series of display, the scan time of the PLC should be 10 ms or more.
If the scan time is less than 10 ms, use the constant scan mode so that the scan time exceeds 10 ms.
4. Number of occupied devices
1) Four input devices are occupied starting from
.
2) Eight output devices are occupied starting from
.
5. Limitation in the number of the instruction
ARWS instruction can be used only once in a program.
When ARWS instruction should be used twice or more, use the indexing (V, Z) function.
S
S
D
1
D
1
D
1
S
D
2
