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2.1
T
ypes of
Instr
uctions
CHAPTER 2
INSTRUCTION TABLES
2.1
Types of Instructions
The major types of CPU module instructions consist of sequence instructions, basic instructions, application instructions, data
link instructions, QCPU instructions and redundant system instructions. These types of instructions are listed in the following
Table.
Types of Instruction
Meaning
Reference
Chapter
Sequence
instruction
Contact instruction
Operation start, series connection, parallel connection
Association instruction
Ladder block connection, store/read operation results, creation of pulses from
operation results
Output instruction
Bit device output, pulse output, output reversal
Shift instruction
Bit device shift
Master control instruction
Master control
Termination instruction
Program termination
Other instruction
Program stop, instructions such as no operation which do not fit in the above
categories
Basic
instruction
Comparison operation
instruction
Comparisons such as , ,
Arithmetic operation
instruction
Addition, subtraction, multiplication or division of BIN or BCD
BCD BIN conversion
instruction
Conversion from BCD to BIN and from BIN to BCD
Data transfer instruction
Transmits designated data
Program branch instruction
Program jumps
Program run control
instruction
Enables or inhibits interrupt programs
I/O refresh
Executes partial refresh
Other convenient instruction
Instructions for: Counter increment/decrement, teaching timer, special
function timer, rotary table shortest direction control, etc.
Application
instruction
Logical operation instruction
Logical operations such as logical sum, logical product, etc.
Rotation instruction
Rotation of designated data
Shift instruction
Shift of designated data
Bit processing instruction
Bit set and reset, bit test, batch reset of bit devices
Data processing instruction
16-bit data searches, data processing such as decoding and encoding
Structure creation instruction Repeated operation, subroutine program calls, indexing in ladder units
Table operation instruction
Data table read/write
Buffer memory access
instruction
Data read/write from/to an intelligent function module
Display instruction
Print ASCII code, LED character display, etc.
Debugging and failure
diagnosis instruction
Check, status latch, sampling trace
Character string processing
instruction
Conversion between BIN/BCD and ASCII;conversion between BIN and
character string; conversion between floating decimal point data and
character strings, character string processing, etc.
Special function instruction
Trigonometric functions, conversion between angles and radians, exponential
operations, automatic logarithms, square roots
Data control instruction
Upper and lower limit controls, dead band controls, zone controls
Switching instruction
File register block No. switches, designation of file registers and comment files