586 Rockwell Automation Publication 1756-RM003N-EN-P - October 2011
Chapter 17 ASCII Serial Port Instructions (ABL, ACB, ACL, AHL, ARD, ARL, AWA, AWT)
Structured Text
The operands are the same as those for the relay ladder AHL instruction.
However, you specify the Channel Status value by accessing the .POS member of
the SERIAL_PORT_CONTROL structure, rather than by including the value
in the operand list.
SERIAL_PORT_CONTROL Structure
AHL(Channel,ANDMask,ORMask,
SerialPortControl);
Mnemonic Data Type Description
.EN BOOL The enable bit indicates that the instruction is enabled.
.EU BOOL The queue bit indicates that the instruction entered the ASCII queue.
.DN BOOL The done bit indicates when the instruction is done, but it is asynchronous to the logic scan.
.RN BOOL The run bit indicates that the instruction is executing.
.EM BOOL The empty bit indicates that the instruction is done, but it is synchronous to the logic scan.
.ER BOOL The error bit indicates when the instruction fails (errors).
.FD BOOL The found bit does not apply to this instruction.
.POS DINT The position stores the status of the control lines.
.ERROR DINT The error contains a hexadecimal value that identifies the cause of an error.
To Next Page
Loading...
Need help?
General
