background image

 

AN-000227

 

 

Document Number: AN-000227

 

Page 10 of 15

 

 

Revision: 1.0  

 

 

Reset the SmartSonic board using the board’s reset button (next to the Programming EDBG connector).  

 

Status messages from the application will appear on the terminal output, followed by summary data from 

the sensor initialization (device frequency, etc.) and configuration (maximum range, etc.).  

 

Measurement data from each sensor device will then be output in a continuous loop. During each 

measurement cycle, a line of output is generated for each sensor. Each line of output includes: 

o

 

Internal timestamp value 

o

 

Sensor number 

o

 

Boolean indicator of whether object presence was detected (0 = no presence, 1 = presence) 

o

 

Range measurement, expressed in millimeters 

o

 

Confidence level (expressed as a percentage). In the presence algorithm the detection of motion 

is based on a criterion passing a threshold. The confidence is derived from the following criterion 

value (the criterion value is defined in the algorithm and is not settable in the end application): 

 

If the criterion < threshold, confidence is 0 (or very low) 

 

If the criterion 

≥ 

10 x threshold, confidence is maximum (100%) 

 

In between the confidence is linearized.  

 

If more than one sensor is used, an additional line of output is generated during each measurement cycle, 

with a merged result based on combined data from all sensors. 

Summary of Contents for SmartSonic CH201

Page 1: ...specifications and information herein without notice Chirp Microsystems 2560 Ninth Street Ste 220 Berkeley CA 94710 U S A 1 510 640 8155 www chirpmicro com Document Number AN 000227 Revision 1 0 Relea...

Page 2: ...d on the presence detection algorithm In this example the application is built using Atmel Studio 7 for the Chirp SmartSonic evaluation board which features an Atmel SAMG55 microcontroller The SmartSo...

Page 3: ...Detection Application 9 Changing the Presence Detection Application Settings 13 6 1 MEASUREMENT_INTERVAL_MS 13 Reference Documents 14 Revision History 15 LIST OF FIGURES Figure 1 SmartSonic with CH20...

Page 4: ...e white arrows Optional Using flat flex cables attach additional off board sensor s to the connectors on the daughterboard If an offboard sensor is connected to the Sensor 0 connector J6 you must set...

Page 5: ...ort number assigned to the SmartSonic board There will be one port associated with the SmartSonic board called EDBG A second COM port will also be assigned but is not used in this application o The ED...

Page 6: ...ion about the operation of the application The application smartsonic presence example inc app_config h file specifies the overall measurement interval The default is 100 ms 10 Hz sample rate o board...

Page 7: ...gramming Screen Verify that the tool is EDBG device is ATSAMG55J19 and interface is SWD Select Apply o Note Atmel Studio 7 may require you to update the EDBG debug interface firmware on the SmartSonic...

Page 8: ...00227 Page 8 of 15 Revision 1 0 Figure 3 Device Signature and Target Voltage Select Memories on the Device Programming menu The Device Programming menu will prompt for the name of the file to program...

Page 9: ...the Atmel Studio 7 debugging features it does not matter which file you use Select Program Your SmartSonic board is successfully programmed when the Device Programming screen displays the OK messages...

Page 10: ...e o Sensor number o Boolean indicator of whether object presence was detected 0 no presence 1 presence o Range measurement expressed in millimeters o Confidence level expressed as a percentage In the...

Page 11: ...orithm detects changes in the ultrasound environment it is normal for the first few measurement cycles to report no presence detected Figure 6 shows the typical application output during initializatio...

Page 12: ...rements has been made the presence of objects can be detected Figure 7 shows typical application output during operation with two sensors The Merged output lines indicate the overall Presence Detectio...

Page 13: ...pplication s timing 6 1 MEASUREMENT_INTERVAL_MS Specifies how often a new measurement cycle will be initiated in milliseconds Default 100 ms 10Hz sample rate This value is used in main as a parameter...

Page 14: ...AN 000227 Document Number AN 000227 Page 14 of 15 Revision 1 0 REFERENCE DOCUMENTS AN 000214 Presence Detection AN 000226 CH201 Ultrasonic Presence Detection Reference Design User Guide...

Page 15: ...the infringement of patents copyrights mask work and or other intellectual property rights Certain intellectual property owned by Chirp Microsystems and described in this document is patent protected...

Reviews: