turck TBEN-S2-2COM-4DXP, Инструкция по эксплуатации

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141
2018/03
9.3.2 Receive Data
The following flow diagram describes the receive sequence.
Receive sequence
Initial state "Receive complete" is FALSE (1).

Set the process output value "Receive" to TRUE (starts the receiver) (2.).

Wait until the process input value "Receive complete" = TRUE or until an error is signaled (3.).

Perform an error handling. If no error is signaled continue with (5.).

Read and process the data received from the receive buffer (5.).

Set the process output value "Receive" to FALSE (stops the receiver) (6.).

Wait until the process input value "Receive complete" = FALSE.

Go back to 1 for the next receive sequence.
The following must be observed for receiving data:
 The receiver temporarily has to be deactivated between two transmit sequences (refer to steps
5…8). The duration for the deactivation depends on the update time set and the PLC cycle time.
During this time, no data can be received.
 The data reception is limited to 192 bytes per telegram.
Fig. 73: Receive sequence
IF Receive complete := FALSE
IF Receive complete := True
WHILE(Receive complete = FALSE
AND Frame error = FALSE
AND parity/format error = FALSE
AND Buffer overflow = FALSE
AND Timeout = FALSE
AND invalid RX length = FALSE
IF(Frame error = TRUE
OR parity/format error = TRUE
OR Buffer overflow = TRUE
OR Timeout = TRUE
OR invalid RX length = TRUE
1. Init
2. Start receiving
Receiver frame length := [expected frame length]1
Receive := TRUE
3. Wait for data
4. Error handling
5. Process received data
6. Reset receiver
Receive := FALSE