Cj (Fnc 00) - Mitsubishi FX1S Series Programming Manual

FX Series Programmable Controlers
5.1.1

CJ (FNC 00)

Mnemonic
CJ
FNC 00
(Conditional
Jump)
16 BIT OPERATION
Points to note:
a) Many CJ statements can reference a single pointer.
b) Each pointer must have a unique number. Using
pointer P63 is equivalent to jumping to the END
instruction.
c) Any program area which is skipped, will not update
output statuses even if the input devices change.
For example, the program opposite shows a
situation which loads X1 to drive Y1. Assuming X1
is ON and the CJ instruction is activated the load
X1, out Y1 is skipped. Now even if X1 is turned
OFF Y1 will remain ON while the CJ instruction
forces the program to skip to the pointer P0. The
reverse situation will also apply, i.e. if X1 is OFF to
begin with and the CJ instruction is driven, Y1 will
not be turned ON if X1 is turned ON. Once the CJ
instruction is deactivated X1 will drive Y1 in the
normal manner. This situation applies to all types of
outputs, e.g. SET, RST, OUT, Y, M & S devices etc.
d) The CJ instruction can jump to any point within the main program body or after an FEND
instruction
Function
Jumps to the Valid pointers from the range 0 to 63
identified pointer
position
32 BIT OPERATION
Operands
D
PULSE-P
Operation:
When the CJ instruction is active it forces the program
to jump to an identified program marker. While the
jump takes place the intervening pro-gram steps are
skipped. This means they are not processed in any
way. The resulting effect is to speed up the programs
operational scan time.
Applied Instructions 5
FX FX FX
1S 1N 2N
Program steps
CJ, CJP:3steps
Jump pointer
P22: 1 step
5-5
FX
2NC