A
PPENDIX
A-4
FT1A S
MART
A
XIS
U
SER
’
S
M
ANUAL
FT9Y-B1382
Processing in One Scan
While the SmartAxis is running, the SmartAXIS performs operations repeatedly such as input refreshing, ladder program
processing, and error checking.
A
scan
is the execution of all instructions from address zero to the END instruction. The time required for this execution is referred
to as one
scan time
. The scan time varies with respect to program length.
The current value of the scan time is stored to special data register D8023 (scan time current value), and the maximum value of
the scan time is stored to special data register D8024 (scan time maximum value). These values can be viewed on the PLC status
screen of WindLDR while monitoring on a PC.
Executing Program Instructions
During the scan time, program instructions are processed sequentially starting with the first line of the ladder program, except for
interrupt program execution. The one scan time of a ladder program is approximately equal to the total of execution time of each
instruction shown on preceding pages.
Watchdog Timer
The watchdog timer monitors the time required for one program cycle (scan time) to prevent hardware malfunction. When the
processing time for one scan exceeds the allowed time, a watchdog timer error occurs and the system is reset. If this is the case,
place NOP instructions in the ladder diagram. The NOP instruction resets the watchdog timer. For details on the watchdog timer,
see Chapter 5 "Special Functions" – "Watchdog Timer" in the FT1A Series Pro/Lite User's Manual.
EXP
F
F
POW
F
F
FIFOF
—
FIEX
—
FOEX
—
NDSRC (W, I)
D, D, D
D
NDSRC (D, L)
D, D, D
D
NDSRC (F)
D, D, D
D
TADD
—
TSUB
—
HOUR
D
D, Y, D
HTOS
—
STOH
D
D
TXD
—
RXD
—
ETXD
—
ERXD
—
DLOG
—
TRACE
—
SCRPT
—
Instruction
Device and Condition
Execution Time (
μ
s)
SmartAXIS Pro / Lite
SmartAXIS Touch
Summary of Contents for microsmart pentra
Page 1: ...FT1A SERIES FC9Y B1382 Ladder Programming Manual ...
Page 6: ...Preface 5 FT1A SMARTAXIS USER S MANUAL FT9Y B1382 ...
Page 104: ...7 DATA COMPARISON INSTRUCTIONS 7 10 FT1A SMARTAXIS USER S MANUAL FT9Y B1382 ...
Page 122: ...8 BINARY ARITHMETIC INSTRUCTIONS 8 18 FT1A SMARTAXIS USER S MANUAL FT9Y B1382 ...
Page 138: ...10 SHIFT ROTATE INSTRUCTIONS 10 12 FT1A SMARTAXIS USER S MANUAL FT9Y B1382 ...
Page 162: ...11 DATA CONVERSION INSTRUCTIONS 11 24 FT1A SMARTAXIS USER S MANUAL FT9Y B1382 ...
Page 188: ...12 CALENDAR COMPARISON INSTRUCTIONS 12 26 FT1A SMARTAXIS USER S MANUAL FT9Y B1382 ...
Page 198: ...15 REFRESH INSTRUCTIONS 15 4 FT1A SMARTAXIS USER S MANUAL FT9Y B1382 ...
Page 202: ...16 INTERRUPT CONTROL INSTRUCTIONS 16 4 FT1A SMARTAXIS USER S MANUAL FT9Y B1382 ...
Page 266: ...20 DUAL TEACHING TIMER INSTRUCTIONS 20 4 FC5A MICROSMART USER S MANUAL FC9Y B1273 ...
Page 318: ...25 USER COMMUNICATION INSTRUCTIONS 25 22 FT1A SMARTAXIS USER S MANUAL FT9Y B1382 ...