TM
Tech note: Instructions for updating ATMOS 41 firmware

Tech note: Instructions for updating ATMOS 41 firmware

These instructions are for the ATMOS 41 weather sensor suite, updating to firmware versions > 4.60.

NOTE: If you are updating from versions > 4.60, then re-zeroing is not required.

A new wind speed algorithm was implemented, which requires a re-zeroing of the wind speed (FW versions < 4.60). First, update the firmware (FW), and then re-zero the instrument. Detailed instructions are shown below. To perform the following actions, you will need access to a ProCheck, terminal application (e.g. TeraTerm), wind shield (such as paper, cardboard, and fleece blanket), and computer with a Windows platform.

  1. Update the ATMOS 41 firmware. Instructions hereNOTE: FW versions > 4.60 don’t require re-zeroing the wind speed.
  2. Steps 2-8 are for re-zeroing the wind speed. After updating the firmware, close the updater utility but keep your ATMOS 41 connected to the ProCheck and computer. Open TeraTerm (or other terminal application), and connect to the ProCheck by selecting Serial and then “METER USB Adapter” in the dropdown menu. Select OK.

In Setup, select Terminal…

  • Under “New-line” “Receive”, select CR+LF.
  • Put a checkmark next to “Local echo”.
  • Press OK.

3. Type [ to enter the direct communication mode on the ProCheck. After entering direct communication mode, if your sensor is address 0 the DDI string will look like a random string of characters (e.g.{&Q^Jy=). Type ?I! to view sensor information.

4. Type ?Xa!0 -0.099 -0.132 0.044 0.079 11.5 12.0 11.0 10.9

The command is shown in blue text, and the output example is shown in red text. If any of the last 4 values are 0, then perform step 5, otherwise skip to step 6.

5. Type ?Xb 0.0 0.0 0.0 0.0 10.0 10.0 10.0 10.0!0OK

Make sure the sensor returns OK. If there is an error, repeat step 5.

The next steps need to be done with the sonic anemometer sensor covered so that there is no air movement! In the field, you will need something better than paper or cardboard when re-zeroing the wind speed. We have found it effective to use paper or cardboard first, then cover the sensor suite in a fleece blanket. This ensures no sound will enter the sensor during the re-zeroing step.

Figure 1. First, use paper or cardboard
Figure 2. Second, cover the sensor suite in a fleece blanket

6. With the sonic anemometer covered, type ?X1!0OK

This will set the phase to zero. Make sure the sensor returns OK. If there is an error, repeat step 6.

7. Type ?X6!0 0.000 -0.000 -0.000 0.000 360 361 360 360 0.00 -0.00 0.00 500

The command is shown in blue text, and the output example is shown in red text. This command returns the SDI-12 sensor address, four phase values, four time of flight values, two wind velocity components, wind speed, and lightning sensor frequency respectively. The phase values should be 0.000 +/- 0.002 when they are set. The time of flight values should be 360 +/- 2 when they are set. The wind velocity and windspeed values should be 0.00 +/- 0.02. The final number is the lightning sensor frequency which can be ignored. Repeat step 6 if the values are outside of the tolerance (see the example below).

8. Exit the terminal program. Remove the wind shield. Reconnect the sensor suite to the data acquisition setup.

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