DVP-ES2-EX2-SS2-SA2-SX2-Operation Manual

3. Instruction Set
API Mnemonic Operands Function
08 FOR Start of a FOR-NEXT Loop
Controllers
ES2/EX2 SS2 SA2
SE
SX2
Type
Bit Devices Word devices Program Steps
OP X Y M S K H KnX KnY KnM KnS T C D E F
S * * * * * * * * * * *
ES2/EX2 SS2 SA2
SE
FOR: 3 steps
PULSE 16-bit 32-bit
SA2
SX2 ES2/EX2 SS2 SX2 ES2/EX2 SS2
SE
SA2
SE
SX2
Operands:
S: The number of times for the loop to be repeated.
API Mnemonic Function
09 NEXT End of a FOR-NEXT Loop
Controllers
ES2/EX2 SS2 SA2
SE
SX2
OP Descriptions Program Steps
N/A No contact to drive the instruction is required. NEXT: 1 step
PULSE 16-bit 32-bit
SA2
SX2 ES2/EX2 SS2 SX2 ES2/EX2 SS2
SE
ES2/EX2 SS2 SA2
SE
SA2
SE
SX2
Explanations:
1. FOR and NEXT instructions are used when loops are needed. No contact to drive the
instruction is required.
2. “N” (number of times loop is repeated) may be within the range of K1 to K32767. If the range
N≦K1, N is regarded as K1.
3. An error will occur in the following conditions:
• NEXT instruction is before FOR instruction.
• FOR instruction exists but NEXT instruction does not exist..
• There is a NEXT instruction after the FEND or END instruction.
• Number of FOR instructions differs from that of NEXT instructinos.
4. FOR~NEXT loops can be nested for maximum five levels. Be careful that if there are too
many loops, the increased PLC scan time may cause timeout of watchdog timer and error.
Users can use WDT instruction to modify this problem.
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