Festo CECX-X-C1 Series, Руководство пользователя

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The Festo_EasyIP.lib library
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1.5.2 Sending telegrams
In the following example, a flag (operand type 1) is increased by 1 during each cycle and sent to the
remote station with the short address 0 (IP = 192.168.0.2). The flag is located at the address %MW500
and is written to the address %MW520 of the remote station. The communication status is written to flag
word %MW600.
Example: Sending a telegram - EasySend (PRG-ST)
PROGRAM EasySend
VAR
Flag AT %MW500: WORD; (*flag variable *)
CommStatus AT %MW600: WORD; (*communication status *)
FunctionStatus: WORD; (*return value from Easy_SR function*)
END_VAR
Flag:= Flag +1; (*increase flag by 1 *)
FunctionStatus := Easy_S(0,1,1,500,520,600),
(*send 1 flag word from the address %MW500 to the address %MW520 of the remote
station *)
1.5.3 Requesting telegrams
When requesting values that will be written to the input area, a pointer is always required because writing
to inputs from the application is not permitted. In the example, an input value from the address %IW2 of
the remote station is requested and written to the input word %IW10. Make sure that an I/O module does
not occupy the input word %IW10 in the control configuration.
Example: Requesting a telegram - EasyRecv (PRG-ST)
PROGRAM EasyRecv
VAR
pInput: POINTER TO WORD; (*pointer variable*)
CommStatus AT %MW600: WORD; (*communication status*)
FunctionStatus: WORD; (*return value from Easy_SR function *)
END_VAR
pInput := 20; (*add offset of 20 bytes in the input area =
IW10*)
pInput^ := pInput^ +1; (* increase the content of pInput by 1 *)
FunctionStatus := Easy_R(0,2,1,10,2,600);
(*request 1 input word from address %IW2 of the remote station and write it to
the local address %IW10 *)
Sending and requesting in a single telegram
This function allows you to send data to a remote station and request data from a remote station at the
same time. When requesting values that will be written to the input area, a pointer is always required
because the IEC does not allow writing to inputs from the application. In the example, an input value from
the address %IW2 of the remote station is requested and written to the input word %IW10. Make sure that
an I/O module does not occupy the input word %IW10 in the control configuration. At the same time, the
output word %QW3 is written to the output word %QW10 of the remote station. The communication status
is written to the flag word %MW600.
Example: Sending and requesting a telegram - EasySendRecv (PRG-ST)
PROGRAM EasySendRecv
VAR
pInput: POINTER TO WORD; (*pointer variable*)
Output AT %QW3: WORD; (* analogue output defined in control
configuration *)
CommStatus AT %MW600: WORD; (*communication status*)
FunctionStatus: WORD; (*return value from Easy_SR function *)
END_VAR
pInput := 20; (*add offset of 20 bytes in the input area =
IW10*)
pInput^ := pInput^ +1; (* increase the content of pInput by 1 *)
FunctionStatus := Easy_SR(0,3,1,3,10,2,1,10,2,600);