ardupilot/APMrover2/failsafe.cpp
Caio Marcelo de Oliveira Filho ee073787c8 Rover: use millis/micros/panic functions
Instead of going through 'hal' then 'scheduler', use directly the AP_HAL
functions. Besides removing indirection that is not necessary for such
functions, this patch ends up reducing the code size in the call sites.

For example, building ArduCopter for PX4 with this change (compared to
before introduction of the functions) yields almost 3k bytes of code
size.

    # ArduCopter build before the functions (1b29a1af46)
       text	   data	    bss	    dec	    hex	filename
     895264	   2812	  62732	 960808	  ea928	/.../px4fmu-v2_APM.build/firmware.elf

    # ArduCopter build after this patch
       text	   data	    bss	    dec	    hex	filename
     892264	   2812	  62732	 957808	  e9d70	/.../px4fmu-v2_APM.build/firmware.elf

A later patch will remove the unused functions in the Schedulers.
2015-11-20 12:26:14 +09:00

54 lines
1.5 KiB
C++

// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
/*
failsafe support
Andrew Tridgell, December 2011
*/
#include "Rover.h"
/*
our failsafe strategy is to detect main loop lockup and switch to
passing inputs straight from the RC inputs to RC outputs.
*/
/*
this failsafe_check function is called from the core timer interrupt
at 1kHz.
*/
void Rover::failsafe_check()
{
static uint16_t last_mainLoop_count;
static uint32_t last_timestamp;
static bool in_failsafe;
uint32_t tnow = AP_HAL::micros();
if (mainLoop_count != last_mainLoop_count) {
// the main loop is running, all is OK
last_mainLoop_count = mainLoop_count;
last_timestamp = tnow;
in_failsafe = false;
return;
}
if (tnow - last_timestamp > 200000) {
// we have gone at least 0.2 seconds since the main loop
// ran. That means we're in trouble, or perhaps are in
// an initialisation routine or log erase. Start passing RC
// inputs through to outputs
in_failsafe = true;
}
if (in_failsafe && tnow - last_timestamp > 20000 &&
channel_throttle->read() >= (uint16_t)g.fs_throttle_value) {
// pass RC inputs to outputs every 20ms
last_timestamp = tnow;
hal.rcin->clear_overrides();
uint8_t start_ch = 0;
for (uint8_t ch=start_ch; ch<4; ch++) {
hal.rcout->write(ch, hal.rcin->read(ch));
}
RC_Channel_aux::copy_radio_in_out(RC_Channel_aux::k_manual, true);
}
}