mirror of
https://github.com/ArduPilot/ardupilot
synced 2025-01-03 22:48:29 -04:00
490841a814
By opening with O_CLOEXEC we make sure we don't leak the file descriptor when we are exec'ing or calling out subprograms. Right now we currently don't do it so there's no harm, but it's good practice in Linux to have it.
69 lines
2.0 KiB
C++
69 lines
2.0 KiB
C++
#include <AP_HAL/AP_HAL.h>
|
|
|
|
#if CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_PXF || \
|
|
CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_ERLEBOARD || \
|
|
CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_BBBMINI
|
|
#include "RCInput_PRU.h"
|
|
|
|
#include <errno.h>
|
|
#include <fcntl.h>
|
|
#include <poll.h>
|
|
#include <stdint.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <sys/mman.h>
|
|
#include <sys/stat.h>
|
|
#include <sys/time.h>
|
|
#include <unistd.h>
|
|
|
|
#include "GPIO.h"
|
|
|
|
#define RCIN_PRUSS_SHAREDRAM_BASE 0x4a312000
|
|
|
|
extern const AP_HAL::HAL& hal;
|
|
|
|
using namespace Linux;
|
|
|
|
void RCInput_PRU::init()
|
|
{
|
|
int mem_fd = open("/dev/mem", O_RDWR|O_SYNC|O_CLOEXEC);
|
|
if (mem_fd == -1) {
|
|
AP_HAL::panic("Unable to open /dev/mem");
|
|
}
|
|
ring_buffer = (volatile struct ring_buffer*) mmap(0, 0x1000, PROT_READ|PROT_WRITE,
|
|
MAP_SHARED, mem_fd, RCIN_PRUSS_SHAREDRAM_BASE);
|
|
close(mem_fd);
|
|
ring_buffer->ring_head = 0;
|
|
_s0_time = 0;
|
|
|
|
// enable the spektrum RC input power
|
|
hal.gpio->pinMode(BBB_P8_17, HAL_GPIO_OUTPUT);
|
|
hal.gpio->write(BBB_P8_17, 1);
|
|
}
|
|
|
|
/*
|
|
called at 1kHz to check for new pulse capture data from the PRU
|
|
*/
|
|
void RCInput_PRU::_timer_tick()
|
|
{
|
|
while (ring_buffer->ring_head != ring_buffer->ring_tail) {
|
|
if (ring_buffer->ring_tail >= NUM_RING_ENTRIES) {
|
|
// invalid ring_tail from PRU - ignore RC input
|
|
return;
|
|
}
|
|
if (ring_buffer->buffer[ring_buffer->ring_head].pin_value == 1) {
|
|
// remember the time we spent in the low state
|
|
_s0_time = ring_buffer->buffer[ring_buffer->ring_head].delta_t;
|
|
} else {
|
|
// the pulse value is the sum of the time spent in the low
|
|
// and high states
|
|
_process_rc_pulse(_s0_time, ring_buffer->buffer[ring_buffer->ring_head].delta_t);
|
|
}
|
|
// move to the next ring buffer entry
|
|
ring_buffer->ring_head = (ring_buffer->ring_head + 1) % NUM_RING_ENTRIES;
|
|
}
|
|
}
|
|
|
|
#endif // CONFIG_HAL_BOARD_SUBTYPE
|