Omron CQM1H - PROGRAM Programming Manual page 224

Basic Ladder Diagrams
00000
00001
00002
Diagram B: Corrected with a Jump
Jumps are created using the JUMP (JMP(04)) and JUMP END (JME(05))
instructions. If the execution condition for a JUMP instruction is ON, the pro-
gram is executed normally as if the jump did not exist. If the execution condi-
tion for the JUMP instruction is OFF, program execution moves immediately to
a JUMP END instruction without changing the status of anything between the
JUMP and JUMP END instruction.
All JUMP and JUMP END instructions are assigned jump numbers ranging
between 00 and 99. There are two types of jumps. The jump number used
determines the type of jump.
A jump can be defined using jump numbers 01 through 99 only once, i.e.,
each of these numbers can be used once in a JUMP instruction and once in a
JUMP END instruction. When a JUMP instruction assigned one of these num-
bers is executed, execution moves immediately to the JUMP END instruction
that has the same number as if all of the instruction between them did not
exist. Diagram B from the TR bit and interlock example could be redrawn as
shown below using a jump. Although 01 has been used as the jump number,
any number between 01 and 99 could be used as long as it has not already
been used in a different part of the program. JUMP and JUMP END require
no other operand and JUMP END never has conditions on the instruction line
leading to it.
JMP(04) 01
Instruction 1
Instruction 2
JME(05) 01
This version of diagram B would have a shorter execution time when IR 00000
was OFF than any of the other versions.
The other type of jump is created with a jump number of 00. As many jumps
as desired can be created using jump number 00 and JUMP instructions
using 00 can be used consecutively without a JUMP END using 00 between
them. It is even possible for all JUMP 00 instructions to move program execu-
tion to the same JUMP END 00, i.e., only one JUMP END 00 instruction is
required for all JUMP 00 instruction in the program. When 00 is used as the
jump number for a JUMP instruction, program execution moves to the instruc-
tion following the next JUMP END instruction with a jump number of 00.
Although, as in all jumps, no status is changed and no instructions are exe-
cuted between the JUMP 00 and JUMP END 00 instructions, the program
must search for the next JUMP END 00 instruction, producing a slightly longer
execution time.
Execution of programs containing multiple JUMP 00 instructions for one
JUMP END 00 instruction is similar to that of interlocked sections. The follow-
ing diagram is the same as that used for the interlock example above, except
redrawn with jumps. The execution of this diagram would differ from that of the
diagram described above (e.g., in the previous diagram interlocks would reset
certain parts of the interlocked section, however, jumps do not affect the sta-
tus of any bit between the JUMP and JUMP END instructions).
Section 4-3
Address Instruction
00000 LD
00001 JMP(04)
00002 LD
00003 Instruction 1
00004 LD
00005 Instruction 2
00006 JME(05)
Operands
00000
01
00001
00002
01
199