Tunnel – Periodic monitoring by 4G/3G/2G of 0-10V sensor activating the power supply of the sensor through a relay output of the modem. Sending to web server using HTTP GET.

Scenario details:

• It is intended to monitor a 0-10V sensor with a 4G/3G/2G modem
• The modem and the sensor will be powered by solar panels, so energy consumption is important
• For this reason, the sensor to be read will be powered through the internal relay with the MTX-IOT-S modem associated with its GPIO8 output. That is, the MTX-IOT-S modem, before reading the sensor, will activate the GPIO8 (internal relay) to supply said sensor 0-10V. After a 5 second wait for sensor stabilization, the MTX-IOT-S modem will read the sensor that will be connected to its AD0 input (which allows an input between 0 and 50V) and then deactivate the relay again to save consumption
• The monitoring must be at certain times (at 00:00 UTC, 06:00 UTC, 14:30 UTC and 18:30 UTC) the data will be stored in the flash memory of the modem (datalogger) and will be sent to a server web via HTTP GET as soon as there is 4G/3G/2G coverage

Solution: MTX-Tunnel firmware + MTX-IoT [4-S-N-N]-STD-N

Configuration example (config.txt file) for the indicated scenario:

Details:

• The frame sent to the server has the following JSON format
  31/01/2020 12:20:33 — {“IMEI”:354033091487838,”TYPE”:”IOS”,”TS”:”2020-01-05T06:00:33Z”,”P”:”12345678”,”IO0”:1,”IO1”:1,”IO2”:1,”IO3”:1,”IO4”:1,”IO5”:0,“IO6”:0,”IO7”:0,”IO8”:1,”AD0”:5935,”AD1”:0}
  Where:
  TYPE: IOS frame type
  IMEI: internal identification of the MTX
  Q: User field specified in the LOGGER_password parameter
  TS: TimeStamp of when data was collected
  IO0: It is the value of the GPIO0 of the modem (not used in this ex.)
  IO1: It is the value of the GPIO1 of the modem (not used in this ex.)
  IO2: It is the value of the GPIO2 of the modem (not used in this ex.)
  IO3: It is the value of the GPIO3 of the modem (not used in this ex.)
  IO4: It is the value of the GPIO4 of the modem (not used in this ex.)
  IO6: It is the value of the GPIO5 of the modem (not used in this ex.)
  IO7: It is the value of the GPIO6 of the modem (not used in this ex.)
  IO8: It is the value of the GPIO7 of the modem (not used in this ex.)
  IO9: It is the value of the GPIO8 of the modem (Internal relay of the modem)
  AD0: It is the value of the AD0 input of the modem (sensor reading 0-10V in millivolts, from 0 to 50000)
  AD1: Is the value of the AD1 input of the modem. Not used in this example
• This example makes use of the files “iologger_start.txt”, “iologger_end.txt”. These text files allow you to enter commands that will be executed automatically BEFORE reading the modem I/O data and AFTER reading. Both files must be placed in the /atscripts folder
  The content of “iologger_start.txt” for this example is as follows:
  EXECUTE AT^MTXTUNNEL=SETIO,8,1
  PAUSE 5
  Basically it executes an AT command that activates the internal relay of the MTX-IOT-S modem (which is associated with the GPIO8) and waits 5 seconds.
  The content of “iologger_end.txt” for this examplei is as follows:
  EXECUTE AT^MTXTUNNEL=SETIO,8,0
  Where the relay (GPIO8) is simply deactivated after reading the 0-10V sensor
• This example makes use of the file “schedule.txt”, whose documentation you will find in this manual, which allows you to enter the execution times of certain AT commands. The content of the file “schedule.txt” (which must be located in the root directory of the modem) for this application is as follows:
  1:-1;0;0;AT^MTXTUNNEL=IOEVENT
  2:-1;6;0;AT^MTXTUNNEL=IOEVENT
  3:-1;14;30;AT^MTXTUNNEL=IOEVENT
  4:-1;18;30;AT^MTXTUNNEL=IOEVENT
  4 times are entered in this file. Every day of the week, at 00:00, 06:00, 14:30 and 18:30 the command AT ^ MTXTUNNEL = IOEVENT will be executed. This AT command will launch the process of reading the modem’s I/O, storing it in the modem’s datalogger and sending it to the web server
• Remember that the modem always works with UTC time
• Properly configure the microswitches of the MTX-IOT-S modem to be able to read voltage in ADC0 (description of the microswitches in the Annexes of the manual)