Open main menu

Changes

31 bytes removed ,  22:22, 26 April 2020
<br />
== LIDAR Sensor ==
The angle of the data is not aligned with the natural axis of the device. It seems that the first sample of the first packet is in fact looking at a -10° angle, not 0°. Needs confirmation.
==== Data Format =format for firmware V2.4 ===(recent production units)
===== Data format for firmware V2.4 (recent production units) =====
A full revolution will yield 90 packets, containing 4 consecutive readings each.
*speed is a two-byte information, little-endian. It represents the speed, in 64th of RPM (aka value in RPM represented in fixed point, with 6 bits used for the decimal part).
*Data 0 to Data 3 are the 4 readings. Each one is 4 bytes long, and organized as follows :
 
<br />
byte 0 : Distance 7:0
Byte 2 and 3 are the LSB and MSB of the strength indication. This value can get very high when facing a retroreflector.
* checksum is a two-byte checksum of the packet.
The algorithm is as follows, provided that `data` is the list of the 20 first bytes, in the same order they arrived in.
return int( checksum )
==== Data format for firmware 2.1 ===(Sparkfun scans, pre-production units) ==== 
The periodicity of the data is 1446 bytes.