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Additional Information CLV61x Dual Port (PROFINET IO)

5.1.6 Send data

The PLC can also send data, such as commands, to the CLV61x Dual Port. This is optional and only

required if actions such as triggering by SOPAS ETcommand must be carried out. In the CLV61x Dual Port,

only commands that produce an echo or response, e.g., SOPAS ET commands, are permitted.

Data can be sent and received independently. It is recommended to first implement data receipt in the PLC

and then to start creating the send routine.

To send data, it must be copied to the output range of the CLV61x Dual Port. The send data is entered

without the STX/ETX frame.

Example:

PLC output range: 4 bytes with content: s R I 0

 Sent as SOPAS command to ID sensor and answered with "sRA ...".

The Send begins by incrementing the TransmitCount-value by 1. The value must run from 1 to 255 and

then start again at 1. The 0 must be omitted.

By copying the TransmitCount to TransmitCountBack, the CLV61x Dual Port confirms that the data has been

sent. Before the next data block can be sent, the PLC must wait until these values are again identical.

If the CLV61x Dual Port has set the TransmitCountBack to 0, it indicates that an error has occurred and the

count must start again. The PLC also has to set the TransmitCount to 0 for approx. 1 second to confirm that

the error was detected. Data can then be sent again.

The cause of an error may be:

• Invalid length > 4000 bytes

• A transmission started with the first block, but subsequent blocks could not be sent or were faulty.

• TransmitCount was not incremented in the correct order.

The counting must be 1, 2, 3, … 255, 1, 2, 3, etc.

Longer send data must be divided into blocks (fragmentation):

If a longer data telegram needs to be sent, it can be transmitted to the CLV61x Dual Port in blocks.

Therefore, start with the first block and always set the length to the data length to be sent. If the block was

answered by the CLV61x Dual Port with TransmitCountBack as a byte handshake, the next block can be

sent and the length decremented. The next block must follow within 10 seconds. Otherwise, a timeout

occurs.

Example:

Transmission of 100 bytes with a block size of 32-byte output (may contain up to 27 bytes in one block)

TransmitCount TransmitLength

TransmitData

100 first 27 data bytes

2 73 next 27 data bytes

46 next 27 data bytes

19 last 19 data bytes

1 2 ... 17 18 19 20 21 22 23 24 25 26 27 ... 51 52

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Siemens ET8 Series Instrucciones de operaciones Pagina 22