ardupilot/libraries/AP_HAL_AVR/GPIO.cpp

161 lines
3.9 KiB
C++

#include <avr/interrupt.h>
#include <avr/io.h>
#include "pins_arduino_mega.h"
#include "GPIO.h"
using namespace AP_HAL_AVR;
AP_HAL::Proc AVRGPIO::_interrupt_6 = NULL;
SIGNAL(INT6_vect) {
if (AVRGPIO::_interrupt_6) {
AVRGPIO::_interrupt_6();
}
}
// Get the bit location within the hardware port of the given virtual pin.
// This comes from the pins_*.c file for the active board configuration.
#define analogInPinToBit(P) (P)
// Get the bit location within the hardware port of the given virtual pin.
// This comes from the pins_*.c file for the active board configuration.
//
// These perform slightly better as macros compared to inline functions
//
#define digitalPinToPort(P) ( pgm_read_byte( digital_pin_to_port_PGM + (P) ) )
#define digitalPinToBitMask(P) ( pgm_read_byte( digital_pin_to_bit_mask_PGM + (P) ) )
#define digitalPinToTimer(P) ( pgm_read_byte( digital_pin_to_timer_PGM + (P) ) )
#define analogInPinToBit(P) (P)
#define portOutputRegister(P) ( (volatile uint8_t *)( pgm_read_word( port_to_output_PGM + (P))) )
#define portInputRegister(P) ( (volatile uint8_t *)( pgm_read_word( port_to_input_PGM + (P))) )
#define portModeRegister(P) ( (volatile uint8_t *)( pgm_read_word( port_to_mode_PGM + (P))) )
void AVRGPIO::pinMode(uint8_t pin, uint8_t mode) {
uint8_t bit = digitalPinToBitMask(pin);
uint8_t port = digitalPinToPort(pin);
volatile uint8_t *reg;
if (port == NOT_A_PIN) return;
// JWS: can I let the optimizer do this?
reg = portModeRegister(port);
if (mode == GPIO_INPUT) {
uint8_t oldSREG = SREG;
cli();
*reg &= ~bit;
SREG = oldSREG;
} else {
uint8_t oldSREG = SREG;
cli();
*reg |= bit;
SREG = oldSREG;
}
}
uint8_t AVRGPIO::read(uint8_t pin) {
uint8_t bit = digitalPinToBitMask(pin);
uint8_t port = digitalPinToPort(pin);
if (port == NOT_A_PIN) return 0;
if (*portInputRegister(port) & bit) return 1;
return 0;
}
void AVRGPIO::write(uint8_t pin, uint8_t value) {
uint8_t bit = digitalPinToBitMask(pin);
uint8_t port = digitalPinToPort(pin);
volatile uint8_t *out;
if (port == NOT_A_PIN) return;
out = portOutputRegister(port);
uint8_t oldSREG = SREG;
cli();
if (value == 0) {
*out &= ~bit;
} else {
*out |= bit;
}
SREG = oldSREG;
}
/* Implement GPIO Interrupt 6, used for MPU6000 data ready on APM2. */
bool AVRGPIO::attach_interrupt(
uint8_t interrupt_num, AP_HAL::Proc proc, uint8_t mode) {
if (!((mode == 0)||(mode == 1))) return false;
if (interrupt_num == 6) {
_interrupt_6 = proc;
EICRB = (EICRB & ~((1 << ISC60) | (1 << ISC61))) | (mode << ISC60);
EIMSK |= (1 << INT6);
return true;
} else {
return false;
}
}
AP_HAL::DigitalSource* AVRGPIO::channel(uint16_t pin) {
uint8_t bit = digitalPinToBitMask(pin);
uint8_t port = digitalPinToPort(pin);
if (port == NOT_A_PIN) return NULL;
return new AVRDigitalSource(bit, port);
}
void AVRDigitalSource::mode(uint8_t output) {
const uint8_t bit = _bit;
const uint8_t port = _port;
volatile uint8_t* reg;
reg = portModeRegister(port);
if (output == GPIO_INPUT) {
uint8_t oldSREG = SREG;
cli();
*reg &= ~bit;
SREG = oldSREG;
} else {
uint8_t oldSREG = SREG;
cli();
*reg |= bit;
SREG = oldSREG;
}
}
uint8_t AVRDigitalSource::read() {
const uint8_t bit = _bit;
const uint8_t port = _port;
if (*portInputRegister(port) & bit) return 1;
return 0;
}
void AVRDigitalSource::write(uint8_t value) {
const uint8_t bit = _bit;
const uint8_t port = _port;
volatile uint8_t* out;
out = portOutputRegister(port);
uint8_t oldSREG = SREG;
cli();
if (value == 0) {
*out &= ~bit;
} else {
*out |= bit;
}
SREG = oldSREG;
}