User manual

Publication 1768-UM001C-EN-P - November 2007
Communicate over Networks 39
Each controller supports several ladder diagram (LD) and structured text (ST)
instructions to manipulate ASCII characters.
Read and Write ASCII Characters
Instruction Command
ABL Determine when the buffer contains termination characters.
ACB Count the characters in the buffer.
ACL Clear the buffer.
Clear out ASCII serial port instructions that are currently executing or are
in the queue.
AHL Obtain the status of the serial port control lines.
Turn the DTR signal on or off.
Turn the RTS signal on or off.
ARD Read a fixed number of characters.
ARL Read a varying number of characters, up to and including the first set of
termination characters.
AWA Send characters and automatically append one or two additional
characters to mark the end of the data.
AWT Send characters.
Create and Modify Strings of ASCII Characters
Instruction Command
CONCAT Add characters to the end of a string.
DELETE Delete characters from a string.
FIND Determine the starting character of a sub-string.
INSERT Insert characters into a string.
MID Extract characters from a string.
Convert Data To or From ASCII Characters
Instruction Command
STOD Convert the ASCII representation of an integer value to a SINT, INT, DINT,
or REAL value.
STOR Convert the ASCII representation of a floating-point value to a REAL
value.
DTOS Convert a SINT, INT, DINT, or REAL value to a string of ASCII characters.
RTOS Convert a REAL value to a string of ASCII characters.
UPPER Convert the letters in a string of ASCII characters to upper case.
LOWER Convert the letters in a string of ASCII characters to lower case.