User Manual

SJ-PM-TFmini-T-01 A03
Benewake (Beijing) Co. Ltd.
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Byte1
0x59, frame header, same for each frame
Byte2
Dist_L distance value lower by 8 bits
Byte3
Dist_L distance value higher by 8 bits
Byte4
Strength_L low 8 bits
Byte5
Strength_L high 8 bits
Byte6
Mode, distance mode, represented respectively by 02 (short distance) and 07 (long distance),
automatically switchable by default.
Byte7
Spare byte, 00 by default
Byte8
CheckSum is the low 8 bits of the cumulative sum of the numbers of the first 8 bytes.
 Serial port Pixhawk data format
The data output is in the format of character string and its unit is m(meter). For example, if the measurement
distance is 1.21m, the string 1.21 will be output, followed by the escape character \r\n.
5.4 Descriptions of default Output Data
Dist: Represents the output of the distance value detected by TFmini, with the unit in cm by default. This
value is interpreted into the decimal value in the range of 0-1200.In the practice, if the signal strength value-
Strength<20 (which is settable), the value of Dist will be deemed as unreliable and FFFF will be output by
default (-1 in case of Pixhawk data format). If Strength≥20 and actual distance >12m, the default output
value of Dist will be 1,200(cm).
Strength：Represents the signal strength with the default value in the range of 0-3,000. After the distance
mode is set, the longer the distance measurement distance is, the lower the signal strength will be; the lower
the reflectivity is, the lower the signal strength will be. It is recommended that the value of Dist be deemed
reliable if Strength is within the range of 20-2,000, which is adjustable by the user at his/her own discretion
depending upon the scenarios of application.
Mode: The parameter used to indicate distance mode of the product. For this parameter, there will be some
differences between different firmware versions, for 15X version of the firmware there are two modes,
namely, 02 and 07, which is short-distance and long-distance operating mode respectively. The default
automatic switchover logic is as the follows: if the value of signal strength is less than a certain value
(generally being 70-120) under 02 distance mode, then the distance mode is switched to 07 automatically,
in which case the value of Strength will be significantly increased; if the value of signal strength is more
than a certain value (generally being 1,200-1,600) under 07 distance mode, the distance mode is switched
to 02, in which case the value of Strength will be significantly decreased. For the 16X version, there are 3
modes 00, 03, and 07. 00 is a short distance mode, 03 is a middle distance mode, and 07 is a long distance
mode. The switchover conditions for the 3 modes are similar to the 2 modes conditions described above.