364
FX
3U
/FX
3UC
Series Programmable Controllers
Programming Manual - Basic & Applied Instruction Edition
14 Handy Instruction – FNC 60 to FNC 69
14.1 FNC 60 – IST / Initial State
14.1
FNC 60 – IST / Initial State
Outline
This instruction automatically controls the initial state and special auxiliary relays in a step ladder program.
→
For SFC programs and step ladder, refer to Chapter 34.
1. Instruction format
2. Set data
3. Applicable devices
S
1: "D
.b" cannot be indexed with index registers (V and Z).
S
2: S20 to S899 and S1000 to S4095
Explanation of function and operation
• Specify the head input in the operation mode in
.
Selector switches in the operation mode occupy eight devices from the head device
, and the switch
functions shown in the table below are assigned to each of them.
When X020 is assigned as shown below, it is necessary to set X020 to X024 as rotary switches so that
they do not turn ON at the same time.
It is not necessary to wire unused switches, but they cannot be used for any other purpose because they
are occupied by IST instruction.
• Specify the smallest device number of practical state relays in
(for the automatic mode).
• Specify the largest device number of practical state relays in
(for the automatic mode).
Operand type
Description
Data type
Head bit device number of the selector switch in the operation mode
Bit
Smallest state relay number of practical state relays in the automatic mode
(
<
)
Bit
Largest state relay number of practical state relays in the automatic mode
(
<
)
Bit
Oper-
and
Type
Bit Devices
Word Devices
Others
System User
Digit Specification
System User
Special
Unit
Index
Con-
stant
Real
Number
Charac-
ter String
Pointer
X Y M T C S D
.b KnX KnY KnM KnS
T
C
D
R U
\G
V
Z Modify K
H
E
"
"
P
3 3 3
S
1
3
S
2
3
S
2
3
Source
Device number (example)
Switch function
X020
Individual operation
+ 1
X021
Return to zero point
+ 2
X022
Stepping
+ 3
X023
Cycle operation
+ 4
X024
Continuous operation
+ 5
X025
Zero return start
+ 6
X026
Automatic start
+ 7
X027
Stop
FNC 60
IST
−
Mnemonic
Operation Condition
16-bit Instruction
7 steps
IST
Mnemonic
Operation Condition
Continuous
Operation
32-bit Instruction
S
1
S
D
1
D
1
D
2
D
2
D
1
D
2
S
1
S
S
2
D
1
D
2
Command
input
FNC 60
IST
S
D
1
D
2
S
S
S
S
S
S
S
S
S
S
D
1
D
2