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ATIM_ACW-D_UG_EN_V1.5
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3: Frames parameters: You can configure a maximum of 6 modbus frames. For each of the frames,
you must specify the Modbus address of the slave '@Device' you wish to interrogate, the register
(word 16bits) from which you want to read '@Registers' as well as the number of words 'Length'
(max 4 words).
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3: Statement period: This is the time between sending each Modbus frame, and therefore also
Sigfox frames if there is no Modbus error.
Modbus Master Mode
Supported Modbus Functions:
Function
Type
0x03 (3)
Read Holding Registers
0x04 (4)
Read Input Registers
Operating mode:
Every 'Statement period', a Modbus frame is sent on the RS232 / 485 serial link. Then, if there are no errors,
the read registers are sent to Sigfox as described in the next section. The following 'Statement period', the
next Modbus frame will be sent (if the last frame corresponds to the 6th the 1st will be sent), even if an error
occurred on the last frame.
Sigfox frame format:
Data of the frame sent to Sigfox are defined in the table below:
Octet :
1
2
3
4
5
6
Donnée :
0x02
@Device
@Registers
MSB
@Registers
LSB
Register1
MSB
Register1
LSB
Octet :
7
8
9
10
11
12
Donnée :
Register2
MSB
Register2
LSB
Register3
MSB
Register3
LSB
Register4
MSB
Register4
LSB
Note:
Only registers read in Modbus will be transmitted to the Sigfox network.
