OEM Environmental Monitor (EMO433, EMO868, EMO915) User Manual v 1.6 December 2021 © Advanced Sensor Research Ltd. https://www.asr-web.
Features • • • • • • • Integrated MCU Corrected atmospheric pressure readings Derived elevations with customizable datum Temperature, humidity and gas readings Mesh networking Simple serial interface Metric or Imperial output units Application Examples • • • • Indoor elevations Building pressurization monitoring Multi-node telemetry networks Altitude reference for UAVs Overview The EMOxxx series differential barometer/altimeter (patent pending) environmental monitor OEM module provides atmospheric press
C) Multi-node telemetry. In this application the rover receives remote uncorrected pressure, temperature, humidity and gas readings from multiple bases using a mesh network topology. The pressure data is absolute and not differentially corrected. Specifications Differential Pressure Accuracy: +/- 0.039 mbar (+/- 0.35cm) RMS Absolute Pressure Accuracy: +/- 0.6 mbar Temperature Accuracy: +/- 0.
1 145 289 433 577 721 865 1009 1153 1297 1441 1585 1729 1873 2017 2161 2305 2449 2593 2737 2881 3025 3169 3313 3457 3601 3745 3889 4033 4177 4321 4465 4609 4753 4897 5041 -1 -0.2 -0.4 1 149 297 445 593 741 889 1037 1185 1333 1481 1629 1777 1925 2073 2221 2369 2517 2665 2813 2961 3109 3257 3405 3553 3701 3849 3997 4145 4293 4441 4589 4737 4885 5033 Typical Characteristics Modules were stationary for testing at a set fixed datum elevation of 0m.
Commands The general command syntax is command,{x{,y}} followed by an exclamation mark (!). Command 1,x! 2,x! 3,x! 4,x,y! 5! 6! 7! 8, x! 9, x! Description Set NetID, both base and rover must match. Valid range is x=1 to 999. Set NodeID, every NodeID on NetID must be unique. Valid range is x=1 to 999. Set Units. Metric x=0 (mb,m, C), Imperial x=1 (inHg,ft, F)). Average Elevation Datum and Base NodeID (differential mode preset, rover only). Valid Elevation Datum range is x=-9999.99 to 9999.99.
Rover output (differential mode) format is as follows, output will be ,A, (preset) until set: NetID,NodeID,D,BaseNodeID,Units, Differential Pressure,Pressure Residual, Local Elevation Datum, Differential Elevation, Elevation Residual*Checksum Checksum is a hex value calculated by applying XOR on each character in the string up to but not including the asterix (*). Base NodeID must be an available node in the rover telemetry stream output for commands 4! and 5! to output differential results.
Demo Software The Differential Barometer Demo software is available for download on our website at https://www.asr-web.com/support and allows users to evaluate the capabilities of the system. Note that a user must be a local administrator on a system in order to install and run this program. After installation edit the settings.txt file in the program installation directory to set the parameters.
When connected to the base, pressure and elevation graphs are absolute readings. The range corresponding to 0 on the graphs is shown in brackets in each title. The buttons on the bottom top row will be labeled NetID (x) where x is the current NetID and NodeID (y) where y is the current NodeID . To set a new NetID or NodeID enter it into the corresponding text box and click the button. In this mode the Ping button is disabled. The current Units can be changed on the bottom.
When connected to the rover, pressure and elevation graphs are absolute readings until a datum is set. The range corresponding to 0 on the graphs is shown in brackets in each title. The buttons on the bottom top row will be labeled NetID (x) where x is the current NetID and NodeID (y) where y is the current NodeID. To set a new NetID or NodeID enter it into the corresponding text box and click the button. In this mode the Ping button is enabled.
Absolute readings for available base telemetry can be viewed by choosing the Base NodeID using the NodeID combo box. To set the Elevation Datum enter it into the text box and click the Datum button. After the Datum button is clicked it will change to Adjust (x) where x is the current Elevation Residual as an average deviation from the preset datum, do not move the units during the calibration.
A log.txt file in the application directory stores the output with a date/time stamp.
Firmware Updates Firmware updates are available for download on our website at https://www.asrweb.com/support. The following is the firmware update procedure: 1. 2. 3. 4. 5. 6. Connect the OEM module to a USB-serial converter, the DSR/DTR line must be used. Connect USB-serial converter to a port on your local machine. Unzip the package. Launch a command window. Change the directory to the location of the package. Invoke update.bat with a single parameter which specifies the serial port number to use.
