mirror of https://github.com/ArduPilot/ardupilot
83 lines
2.4 KiB
C++
83 lines
2.4 KiB
C++
|
/*
|
||
|
|
This program is free software: you can redistribute it and/or modify
|
||
|
|
it under the terms of the GNU General Public License as published by
|
||
|
|
the Free Software Foundation, either version 3 of the License, or
|
||
|
|
(at your option) any later version.
|
||
|
|
|
||
|
|
This program is distributed in the hope that it will be useful,
|
||
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
|
|
GNU General Public License for more details.
|
||
|
|
|
||
|
|
You should have received a copy of the GNU General Public License
|
||
|
|
along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||
|
|
*/
|
||
|
|
/*
|
||
|
|
driver for Lanbao PSK-CM8JL65-CC5 Lidar
|
||
|
|
*/
|
||
|
|
#include <AP_HAL/AP_HAL.h>
|
||
|
|
#include "AP_RangeFinder_Lanbao.h"
|
||
|
|
#include <AP_Math/crc.h>
|
||
|
|
#include <stdio.h>
|
||
|
|
|
||
|
|
extern const AP_HAL::HAL& hal;
|
||
|
|
|
||
|
|
/*
|
||
|
|
this sensor has no way of reporting "out of range", it will keep
|
||
|
|
reporting distances at of around 7 to 8 meters even when pointed at
|
||
|
|
the sky. For this reason we limit the max range to 6 meters as
|
||
|
|
otherwise we may be giving false data
|
||
|
|
*/
|
||
|
|
#define LANBAO_MAX_RANGE_CM 600
|
||
|
|
|
||
|
|
// read - return last value measured by sensor
|
||
|
|
bool AP_RangeFinder_Lanbao::get_reading(uint16_t &reading_cm)
|
||
|
|
{
|
||
|
|
if (uart == nullptr) {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
|
||
|
|
float sum_range = 0;
|
||
|
|
uint32_t count = 0;
|
||
|
|
|
||
|
|
// format is: [ 0xA5 | 0x5A | distance-MSB-mm | distance-LSB-mm | crc16 ]
|
||
|
|
|
||
|
|
// read any available lines from the lidar
|
||
|
|
int16_t nbytes = uart->available();
|
||
|
|
while (nbytes-- > 0) {
|
||
|
|
int16_t b = uart->read();
|
||
|
|
if (b == -1) {
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
if (buf_len == 0 && b != 0xA5) {
|
||
|
|
// discard
|
||
|
|
continue;
|
||
|
|
}
|
||
|
|
if (buf_len == 1 && b != 0x5A) {
|
||
|
|
// discard
|
||
|
|
if (b == 0xA5) {
|
||
|
|
buf[0] = b;
|
||
|
|
} else {
|
||
|
|
buf_len = 0;
|
||
|
|
}
|
||
|
|
continue;
|
||
|
|
}
|
||
|
|
buf[buf_len++] = b;
|
||
|
|
if (buf_len == sizeof(buf)) {
|
||
|
|
buf_len = 0;
|
||
|
|
uint16_t crc = (buf[5]<<8) | buf[4];
|
||
|
|
if (crc != calc_crc_modbus(buf, 4)) {
|
||
|
|
// bad CRC, discard
|
||
|
|
continue;
|
||
|
|
}
|
||
|
|
sum_range += float((buf[2]<<8) | buf[3]) * 0.001;
|
||
|
|
count++;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
if (count > 0) {
|
||
|
|
reading_cm = (sum_range / count) * 100;
|
||
|
|
return reading_cm <= LANBAO_MAX_RANGE_CM?true:false;
|
||
|
|
}
|
||
|
|
return false;
|
||
|
|
}
|