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en:software:devices:modbus [2016/12/21 17:40] – [Read Input Register] qem103 | en:software:devices:modbus [2016/12/21 17:46] – [5.4. Richieste di scrittura] qem103 | ||
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=== Read Holding Register === | === Read Holding Register === | ||
- | Word read function. | + | Word read function. |
You must to set addr to indicate the address of the word in the slave from which to start reading. The num parameter indicates the number of word to be read. You must set tabreg to indicate the index of the word in the “read data table” of the master from which you want are writes the read words. The read values will be saved in the “read data table”. It is recommended to always meet the following two conditions: | You must to set addr to indicate the address of the word in the slave from which to start reading. The num parameter indicates the number of word to be read. You must set tabreg to indicate the index of the word in the “read data table” of the master from which you want are writes the read words. The read values will be saved in the “read data table”. It is recommended to always meet the following two conditions: | ||
(addr + num - 1) <= 32 e (tabreg + num - 1) <= 32 otherwise the request will fail (reporting by wcmd). | (addr + num - 1) <= 32 e (tabreg + num - 1) <= 32 otherwise the request will fail (reporting by wcmd). | ||
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=== Read Input Register === | === Read Input Register === | ||
- | Word read function. | + | Word read function. |
- | ==== - Richieste di scrittura | + | ==== - Write request |
=== Force coil === | === Force coil === |