FX Series Programmable Controlers Applied Instructions 5
5-92
5.7.7 ALT (FNC 66)
Operation:
The status of the destination device (D) is
alternated on every operation of the ALT
instruction.
This means the status of each bit device will flip-
flop between ON and OFF. This will occur on every
program scan unless a pulse modifier or a program
interlock is used.
The ALT instruction is ideal for switching between
two modes of operation e.g. start and stop, on and
off etc.
Mnemonic Function
Operands
Program steps
D
ALT
FNC 66
(Alternate
state)
The status of the
assigned device
is inverted on
every operation of
the instruction
Y, M, S ALT, ALTP:
3steps
FX
1S
FX
1N
FX
2N
FX
2NC
PULSE-P
16 BIT OPERATION
32 BIT OPERATION
ALT M 0
X0
[ D ]
M0
X0