Files
2024-07-20 22:09:06 +08:00

113 lines
2.6 KiB
C

#include "pins_arduino.h"
volatile uint8_t *port_to_pcmask[] = { &PCMSK0, &PCMSK1, &PCMSK2 };
static int PCintMode[24];
typedef void (*voidFuncPtr)(void);
volatile static voidFuncPtr PCintFunc[24] = { NULL };
volatile static uint8_t PCintLast[3];
/*
* attach an interrupt to a specific pin using pin change interrupts.
*/
void PCattachInterrupt(uint8_t pin, void (*userFunc)(void), int mode) {
uint8_t bit = digitalPinToBitMask(pin);
uint8_t port = digitalPinToPort(pin);
uint8_t slot;
volatile uint8_t *pcmask;
// map pin to PCIR register
if (port == NOT_A_PORT) {
return;
} else {
port -= 2;
pcmask = port_to_pcmask[port];
}
// -- Fix by Baziki. In the original sources it was a little bug, which cause analog ports to work incorrectly.
if (port == 1) {
slot = port * 8 + (pin - 14);
} else {
slot = port * 8 + (pin % 8);
}
// --Fix end
PCintMode[slot] = mode;
PCintFunc[slot] = userFunc;
// set the mask
*pcmask |= bit;
// enable the interrupt
PCICR |= 0x01 << port;
// Fix init by SkyWodd
PCintLast[0] = *portInputRegister(2);
PCintLast[1] = *portInputRegister(3);
PCintLast[2] = *portInputRegister(4);
}
void PCdetachInterrupt(uint8_t pin) {
uint8_t bit = digitalPinToBitMask(pin);
uint8_t port = digitalPinToPort(pin);
volatile uint8_t *pcmask;
// map pin to PCIR register
if (port == NOT_A_PORT) {
return;
} else {
port -= 2;
pcmask = port_to_pcmask[port];
}
// disable the mask.
*pcmask &= ~bit;
// if that's the last one, disable the interrupt.
if (*pcmask == 0) {
PCICR &= ~(0x01 << port);
}
}
// common code for isr handler. "port" is the PCINT number.
// there isn't really a good way to back-map ports and masks to pins.
static void PCint(uint8_t port) {
uint8_t bit;
uint8_t curr;
uint8_t mask;
uint8_t pin;
// get the pin states for the indicated port.
curr = *portInputRegister(port + 2);
mask = curr ^ PCintLast[port];
PCintLast[port] = curr;
// mask is pins that have changed. screen out non pcint pins.
if ((mask &= *port_to_pcmask[port]) == 0) {
return;
}
// mask is pcint pins that have changed.
for (uint8_t i = 0; i < 8; i++) {
bit = 0x01 << i;
if (bit & mask) {
pin = port * 8 + i;
// Trigger interrupt if mode is CHANGE, or if mode is RISING and
// the bit is currently high, or if mode is FALLING and bit is low.
if ((PCintMode[pin] == CHANGE
|| ((PCintMode[pin] == RISING) && (curr & bit))
|| ((PCintMode[pin] == FALLING) && !(curr & bit)))
&& (PCintFunc[pin] != NULL)) {
PCintFunc[pin]();
}
}
}
}
SIGNAL(PCINT0_vect) {
PCint(0);
}
SIGNAL(PCINT1_vect) {
PCint(1);
}
SIGNAL(PCINT2_vect) {
PCint(2);
}