
3 Basics | IL•1F CANopen DS301 |
3.3.4Reading and writing data
Writing data The client starts a write request by sending index, subindex, data length and value.
The server sends a confirmation indicating whether the data was cor- rectly processed. The confirmation contains the same index and subindex, but no data.
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write request |
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| ccd | Idx2 Idx1 Sidx |
| data |
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| ccd= 23h |
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| ccd= 27h |
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| ccd= 2Bh |
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| ccd= 2Fh |
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| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
| write response |
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ccd Idx2 Idx1 Sidx |
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ccd= 60h |
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Figure 3.13 Writing parameter values
Unused bytes in the data field are shown with a slash in the graphic. The content of these data fields is not defined.
ccd coding The table below shows the command code for writing parameter values. It depends on the message type and the transmitted data length.
Message type | Data length used |
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| 4 bytes | 3 bytes | 2 bytes | 1 byte |
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Write request | 23h | 27h | 2Bh | 2Fh | Transmitting param- |
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Write response | 60h | 60h | 60h | 60h | Confirmation |
Error response | 80h | 80h | 80h | 80h | Error |
Table 3.5 Command code for writing parameter values
0198441113586, V2.01, 11.2008
28 | Fieldbus interface |