sigfox MODBUS MASTER - Guide utilisateur / User guide version V2.0.0
2.1.4 Application operation
2.1.5 Periodic transmission
The product allows the measurement and the periodic transmission of the VALUE s of the sensors according to the following diagram:
Product in standby
No
Period
reached?
Yes
Read slave register (s)
Send periodic frame
Example:
Register
S301
S322
S330
S331
The product can send up to 6 different periodic frames with different transmission period
configurable :
•
Frame 0x44 being frame 1
•
Frame 0x5F being frame 2
•
Frame 0x60 being frame 3
•
Frame 0x61 being frame 4
•
Frame 0x62 being frame 5
•
Frame 0x63 being frame 6
The parameters associated with this mode of operation are:
•
Transmission period (register S301 or S323, S324, S325, S326, S327 depending on the
concerned frame)
•
External load supply time before the Modbus request (register S322)
•
Definition of periodic data (registers S330 to S349)
VALUE encoding
VALUE
Decimal
360
Decimal
200
Hexadecimal
0x01151812
Hexadecimal
0x570ED814
Result
Periodic mode with a period of 360x10s = 3600 seconds =
1 hour
The supply time of the external load (slave) before the
Modbus request is 200 x 100 = 20 000ms ie 20s
Periodic data 1 configuration:
•
Slave address = 0x01
•
First register address = 0x1518
•
Periodic frame chosen = Periodic frame 1
•
Modbus registers type : holding registers
•
Number of registers = 2
Periodic data 1 configuration:
•
Slave address = 0x57
•
First register address = 0x0ED8
•
Periodic frame chosen = Periodic frame 1
•
Modbus registers type : input registers
•
Number of registers = 4
FR
EN
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