FastIO library

FastIO support for SR class SR Example Small adaptions to make things work with eclipse too
2012-01-21 01:49:42 +01:00
parent e7526e7a34
commit 7b2a7290c6
12 changed files with 337 additions and 41 deletions
@@ -0,0 +1,127 @@
+#if (ARDUINO <  100)
+#include <WProgram.h>
+#else
+#include <Arduino.h>
+#endif
+#include "FastIO.h"
+#include <util/delay.h>
+
+fio_register fio_pinToOutputRegister(uint8_t pin){
+	pinMode(pin, OUTPUT);
+	digitalWrite(pin, LOW); // also turns off pwm timer
+#ifdef FIO_FALLBACK
+	//  just wasting memory if not using fast io...
+	return 0;
+#else
+	return portOutputRegister(digitalPinToPort(pin));
+#endif
+}
+
+fio_register fio_pinToInputRegister(uint8_t pin){
+	pinMode(pin, INPUT);
+	digitalWrite(pin, LOW); // also turns off pwm timer and pullup
+#ifdef FIO_FALLBACK
+	//  just wasting memory if not using fast io...
+	return 0;
+#else
+	return portInputRegister(digitalPinToPort(pin));
+#endif
+}
+
+uint8_t fio_pinToBit(uint8_t pin){
+#ifdef FIO_FALLBACK
+	// (ab)use the bit variable to store the pin
+	return pin;
+#else
+	return digitalPinToBitMask(pin);
+#endif
+}
+
+void fio_digitalWrite(fio_register pinRegister, uint8_t pinBit, uint8_t value) {
+#ifdef FIO_FALLBACK
+	digitalWrite(pinBit, value);
+#else
+	if(value == LOW){
+		fio_digitalWrite_LOW(pinRegister,pinBit);
+	}else{
+		fio_digitalWrite_HIGH(pinRegister,pinBit);
+	}
+#endif
+}
+
+int fio_digitalRead(fio_register pinRegister, uint8_t pinBit){
+#ifdef FIO_FALLBACK
+	return digitalRead(pinBit);
+#else
+	if (*pinRegister & pinBit) return HIGH;
+	return LOW;
+#endif
+}
+
+void fio_shiftOut(fio_register dataRegister, fio_bit dataBit, fio_register clockRegister, fio_bit clockBit, uint8_t value){
+	// # disable interrupts
+	// uint8_t oldSREG = SREG;
+	// cli();
+
+	for(int8_t i = 7; i>-1; --i){
+		fio_digitalWrite(dataRegister, dataBit, !!(value & (1 << i)));
+		fio_digitalWrite_HIGH(clockRegister, clockBit);
+		fio_digitalWrite_LOW(clockRegister, clockBit);
+	}
+
+	// # enable interrupts
+	// SREG = oldSREG;
+}
+
+void fio_shiftOut(fio_register dataRegister, uint8_t dataBit, fio_register clockRegister, uint8_t clockBit){
+	fio_digitalWrite_LOW(dataRegister, dataBit);
+	for(uint8_t i = 0; i<8; ++i){
+			fio_digitalWrite_HIGH(clockRegister, clockBit);
+			fio_digitalWrite_LOW(clockRegister, clockBit);
+	}
+}
+
+void fio_shiftOut1_init(fio_register shift1Register, fio_bit shift1Bit){
+	// Make sure that capacitors are charged
+	fio_digitalWrite(shift1Register,shift1Bit,HIGH);
+	delayMicroseconds(300);
+}
+void fio_shiftOut1(fio_register shift1Register, fio_bit shift1Bit, uint8_t value){
+
+	// disable interrupts since timing is going to be critical
+	uint8_t oldSREG;
+	oldSREG = SREG;
+	cli();
+
+
+	// note: profiling showed that shift out takes 18us longer than the sum of needed delays
+
+	// iterate but ignore last byte (must be LOW)
+	for(int8_t i = 7; i>0; --i){
+		fio_digitalWrite_LOW(shift1Register,shift1Bit);
+		if(LOW==!!(value & (1 << i))){
+			// LOW = 0 Bit
+			// hold pin LOW for 15us
+			delayMicroseconds(14);
+			fio_digitalWrite_HIGH(shift1Register,shift1Bit);
+			// hold pin HIGH for 30us
+			delayMicroseconds(29);
+		}else{
+			// HIGH = 1 Bit
+			//hold pin LOW for 1us - did that already
+			fio_digitalWrite_HIGH(shift1Register,shift1Bit);
+			//hold pin HIGH for 15us
+			delayMicroseconds(14);
+		}
+	}
+	// send last bit (=LOW) and Latch command
+	fio_digitalWrite_LOW(shift1Register,shift1Bit);
+	delayMicroseconds(199); // Hold pin low for 200us
+	fio_digitalWrite_HIGH(shift1Register,shift1Bit);
+	delayMicroseconds(299); // Hold pin high for 300us
+
+	// enable interrupts
+	SREG = oldSREG;
+
+}
+