Benewake (Beijing) Co. Ltd.
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5.4 Basic data output
TF-Luna normally provide these data below:
Distance (Dist): Default in centimeters.
Signal strength (Amp): Distance value is unreliable when receiving signal is overexposure (Amp =
0xFFFF) or too low (Amp < 100 as 14).
Chip Temperature (Temp): Celsius degree = Temp/8 - 256℃
TF-Luna supports various serial format, please check Appendix I Serial port output format for more
information, and the default setting is 9-bytes/centimeter. Format setting is in “Output format setting
ID_OUTPUT_FORMAT=0x05” section.
5.5 Continuous ranging mode
TF-Luna will keep tracking the distance 500 time per second, but as the customized output frequency
is lower, the output may take the average. For instance, if the output frequency is 100Hz as default, then
the output values are the average (arithmetic mean) of 5 previous range data. Therefore, lower output
frequency gives less time of the averaging process as well as less fluctuation of the output. The highest
output frequency that TF-Luna supports is 250Hz (output_frequency ≤ 250Hz), and it must be 500/n Hz (n
is an integer that in the range [2, 500]). Thus, all supported values of output frequency are: 250Hz, 166Hz,
125Hz, 100Hz, …, 2Hz, 1Hz. User can change the output frequency using “Output frequency
ID_SAMPLE_FREQ=0x03”.
5.6 Trigger mode
TF-Luna enters trigger mode if the output frequency is set to be 0 with “Output frequency
ID_SAMPLE_FREQ=0x03”. In this mode, TF-Luna stops measuring and outputting unless it is triggered by
“Trigger mode ID_SAMPLE_TRIG=0x04” — in other words, TF-Luna measures and output once as soon as
it receive the hexadecimal byte string 5A 04 04 00.