0198441113843, V1.01, 01.2012
LXM32M | 3 Basics |
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PV The double word "PV" contains the parameter value.
In the case of a read request, the value in the transmit data has no significance. The receive data contains the parameter value.
In the case of a write request, the transmit data contains the value to be written to the parameter. The receive data contains the parameter value.
If a read request or a write request were not successful, the double word "PV" contains the error number of the error.
Example: Reading a parameter In the example, the program number of the product is read from the parameter _prgNoDEV. The parameter _prgNoDEV has the parame- ter address 258 (01h 02h).
The parameter value read has the decimal value 91200 which corre- sponds to 01h 64h 40h.
Transmit data:
Ctrl | Subindex | Index | PV |
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12h | 00h | 01h 02h | 00h 00h 00h 00h |
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Receive data:
Ctrl | Subindex | Index | PV |
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22h | 00 h | 01h 02h | 00h 01h 64h 40h |
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Example: Writing of an invalid In this example, the value of a
The value of the parameters is to be changed to 222 (DEh).
Before the slave can accept a new request, the value 02h must first be transmitted in byte "Ctrl".
Since the slave cannot address the parameter, a synchronous error message is transmitted with the receive data. Byte "Ctrl" is set to 72h. Double word "PV" is set to the error number (error number 1101h: Parameter does not exist).
Transmit data:
Ctrl | Subindex | Index | PV |
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32h | 00h | 00h 65h | 00h 00h 00h DEh |
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Receive data:
Ctrl | Subindex | Index | PV |
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72h | 00h | 00h 65h | 00h 00h 11h 01h |
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See the product manual for information on the error numbers.
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