ECargosens: Difference between revisions
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- '''RSSI''' as calculated by the central unit for every Sensor in particular; | - '''RSSI''' as calculated by the central unit for every Sensor in particular; | ||
==== '''<big>Note for developers:</big>''' ==== | |||
The central unit retransmits the parameters as per the LLS protocol in response to the request for level and temperature (because the LLS protocol was initially designed for the transmission of fuel level sensor) | |||
31$XX$06$CRC-8 Maxim (XX stands for the network address from 00 to FF in HEX (0…255 in DEC)); | |||
The data output is transmitted as 3E$XX$06$TT$LVLV$CRC-8 Maxim, where | |||
XX -network address, | |||
TT - temperature parameter (1 byte, HEX value), | |||
LVLV - level value (2 bytes, little endian); | |||
Thus, one network address is used to transmit one pair of parameters sent by the Sensor(s) and retransmitted by the central unit. | |||
The Pressure readings is transmitted after it is divided by 100. F.e. the Pressure reading is 700345 Pa but the value transmitted via the RS-485 interface will be 7003. | |||
{| class="wikitable" | |||
|+Table 1. Parameter table | |||
!Pair of parameters (as indicated in the RS-485 settings of the central unit) | |||
!Temperature parameter | |||
!Level parameter | |||
|- | |||
| | |||
|RSSI | |||
|Weight | |||
|- | |||
| | |||
|RSSI | |||
|Pressure | |||
|- | |||
| | |||
|Vbat | |||
|Weight | |||
|- | |||
| | |||
|Vbat | |||
|Pressure | |||
|- | |||
| | |||
|RSSI | |||
|Vbat | |||
|} | |||
'''ATTENTION!''' The tracker/gateway you plan to connect the central unit to must have the RS-485 interface, the LLS protocol and support as many network addresses as you need for the transmission of all relevant Sensor’s parameters. | |||
= '''<big>Installation and configuration</big>''' = | = '''<big>Installation and configuration</big>''' = | ||