Environdata MB40, Handbook

Page: 10 / 21

MB40 & MB45 MODBUS TCP/IP Gateway Page 9 of 21
Weather Station Data
The gateway operates as a Modbus slave. To access the holding registers in the gateway, the PLC or
RTU must be configured as a Modbus Master. Using Modbus Function 3, the PLC can read the
Holding Registers.
Current Weather Data
Table 11: R3 Modbus Register Listing
Holding Register
Address 40,000+ No. of
Registers Type Description
1 1 Time Year in format YYYY
2 1 Time Month and day in format MMDD
3 1 Time Hour in format HH
4 1 Time Minute and second in format MMSS
5 to 59 1 Data Unpacked weather data. Up to 54 “pieces” of comma separated
data is sequentially unpacked and placed into holding registers.
60 1 Status Comms status for the R3 command. 0 = bad, 1 = good.
Daily Weather Data
Table 12: MEM 1 LAST Modbus Register Listing
Holding Register
Address 40,000+ No. of
Registers Type Description
61 1 Time Year in format YYYY
62 1 Time Month and day in format MMDD
63 1 Time Hour in format HH
64 1 Time Minute and second in format MMSS
65 to 119 1 Data
Unpacked weather data. Up to 54 “pieces” of comma separated
data is sequentially unpacked and placed into holding registers.
120 1 Status Comms status for the MEM 1 LAST command. 0 = bad, 1 = good.
Last Hourly Data
Table 13: MEM 2 LAST Modbus Register Listing
Holding Register
Address 40,000+ No. of
Registers Type Description
121 1 Time Year in format YYYY
122 1 Time Month and day in format MMDD
123 1 Time Hour in format HH
124 1 Time Minute and second in format MMSS
125 to 179 1 Data
Unpacked weather data. Up to 54 “pieces” of comma separated
data is sequentially unpacked and placed into holding registers.
180 1 Status Comms status for the MEM 2 LAST command. 0 = bad, 1 = good.