3. Instructions
784
CS/CJ/NSJ Series Instructions Reference Manual (W474)
SNXT/STEP
Applicable Program Areas
Operands
z Operand Specifications
Flags
Function
z SNXT(009)
SNXT(009) is used in the following three ways:
1.To start step programming execution.
2. To proceed to the next step control bit.
3. To end step programming execution.
The step program area is from the first STEP(008) instruction (which always takes a control bit) to the
last STEP(008) instruction (which never takes a control bit).
Starting Step Execution
SNXT(009) is placed at the beginning of the step program area to start step execution. It turns ON
the control bit specified for B for the next STEP(008) and proceeds to step B (all instructions after
STEP(008) B). A differentiated execution condition must be used for the SNXT(009) instruction that
starts step programming area execution, or step execution will last for only one cycle.
Instruction Mnemonic Variations
Function
code
Function
STEP START SNXT --- 009
SNXT(009) is used to control progression of step
execution in the step program area.
STEP DEFINE STEP --- 008
STEP(008) is used to define the beginning and
the end of the step program area.
Symbol
SNXT STEP
When defining the beginning of a step, a control bit is specified as
follows:
When defining the end of a step, a control bit is not specified as
follows:
Area
Function block
definitions
Block program areas Step program areas Subroutines Interrupt tasks
SFC action or
transition programs
Usage Not allowed Not allowed OK Not allowed Not allowed Not allowed
Operand Description Data type Size
BBit --- 1
Area
Word addresses
Indirect DM/EM
addresses
Con-
stants
Registers Flags
Pulse
bits
TR
bits
CIO WR HR AR T C DM EM
@DM
@EM
*DM
*EM
DR IR
Indirect
using IR
TK CF
B --- OK --- --- --- --- --- --- --- ---
---
--- --- OK --- --- --- ---
Name Label
Operation
SNXT STEP
Error Flag ER • ON when the specified bit B is not in the WR
area.
• ON when SNXT(009) is used in an interrupt pro-
gram.
• OFF in all other cases.
• ON when the specified bit B is not in the WR
area.
• ON when STEP(008) is used in an interrupt pro-
gram.
• OFF in all other cases.
B: Bit
SNXT(009)
B
B: Bit
STEP(008)
B
STEP(008)
To Next Page
Loading...
Need help?
General
