Mitsubishi Electronics FX3G Manuale Utente

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FX
3S
/FX
3G
/FX
3GC
/FX
3U
/FX
3UC
 Series
Programming Manual - Basic & Applied Instruction Edition
15 External FX I/O Device – FNC 70 to FNC 79
15.5 FNC 74 – SEGL / Seven Segment With Latch
Cautions
1. Time to update the 4-digit seven-segment display
The scan time (operation cycle) multiplied by 12 is required to update (one or two sets of) the 4-digit display.
2. Operation when the command input turns OFF
While the command input is ON, the operation is repeated.
When the command contact is set to OFF in the middle of an operation, the operation is paused. When the command
contact is set to ON again, the operation is started from the beginning.
3. Number of occupied devices
When one set of 4 digits is used:
1 device is occupied from the head device specified in 
.
8 devices are occupied from the head device specified in 
. Even if the
number of digits is smaller than 4, unused devices cannot be used for any
other purpose.
When two sets of 4 digits are used:
2 devices are occupied from the head device specified in 
.
Twelve devices are occupied from the head device specified in 
. Even
if the number of digits is smaller than 4, unused devices cannot be used for
any other purpose.
4. Scan time (operation cycle) and the display timing
SEGL 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.
5. Caution on use in timer interrupt programs
When the SEGL instruction is used in a timer interrupt program, it turns ON M8029 in the interrupt program.
→ For details, refer to Subsection 36.5.2.
6. Output type of the PLC
Use a transistor output type PLC.
   
S
   
D
   
S
   
D