More work on PWM and added utility function to map values.

ard/pins.c

@@ -34,7 +34,7 @@ void pin_mode(unsigned char pin, unsigned char mode){
 			DDRD |= _BV(pin);
 		}
 	}
-	else if(pin < 14){
+	else if(pin < A0){
 		// digital pin 8-13
 		pin -= 8;
 
@@ -47,7 +47,7 @@ void pin_mode(unsigned char pin, unsigned char mode){
 	}
 	else{
 		// analog pin 0-7
-		pin -= 14;
+		pin -= A0;
 
 		if(mode == INPUT){
 			DDRC &= ~_BV(pin);
@@ -59,27 +59,31 @@ void pin_mode(unsigned char pin, unsigned char mode){
 }
 
 int digital_read(unsigned char pin){
-	if(pin > 13){
+	if(pin > A7){
 		return 0;
 	}
 
 	if(pin < 8){
-		// pin 0-7
+		// digital pin 0-7
 		return PIND&_BV(pin) ? 1 : 0;
 	}
+	else if(pin < A0){
+		// digital pin 8-13
+		pin -= 8;
+		return PINB&_BV(pin) ? 1 : 0;
+	}
 
-	// pin 8-13
-	pin -= 8;
-	return PINB&_BV(pin) ? 1 : 0;
+	// analog pin 0-7
+	return analog_read(pin) > 512 ? 1 : 0;
 }
 
 void digital_write(unsigned char pin, unsigned char value){
-	if(pin > 13){
+	if(pin > A7){
 		return;
 	}
 
 	if(pin < 8){
-		// pin 0-7
+		// digital pin 0-7
 		if(value == HIGH){
 			PORTD |= _BV(pin);
 		}
@@ -87,8 +91,8 @@ void digital_write(unsigned char pin, unsigned char value){
 			PORTD &= ~_BV(pin);
 		}
 	}
-	else{
-		// pin 8-13
+	else if(pin < A0){
+		// digital pin 8-13
 		pin -= 8;
 
 		if(value == HIGH){
@@ -98,6 +102,17 @@ void digital_write(unsigned char pin, unsigned char value){
 			PORTB &= ~_BV(pin);
 		}
 	}
+	else{
+		// analog pin 0-7
+		pin -= A0;
+
+		if(value == HIGH){
+			PORTC |= _BV(pin);
+		}
+		else{
+			PORTC &= ~_BV(pin);
+		}
+	}
 }
 
 unsigned int analog_read(unsigned char pin){
@@ -121,19 +136,22 @@ unsigned int analog_read(unsigned char pin){
 	return ADC;
 }
 
+// TODO: write PWM to digital pins which allow it
 void analog_write(unsigned char pin, unsigned int value){
-	pin = map_analog_pin(pin);
-
-	if(pin > 7){
+	if(pin > 11){
 		return;
 	}
 
-	if(value == HIGH){
+	if(value > 255){
+		value = 255;
+	}
+
+	/*if(value == HIGH){
 		PORTC |= _BV(pin);
 	}
 	else{
 		PORTC &= ~_BV(pin);
-	}
+	}*/
 }
 
 // maps A0-A7 to 0-7

ard/pins.h

@@ -1,5 +1,5 @@
-#ifndef PINS_H_
-#define PINS_H_
+#ifndef ARD_PINS_H_
+#define ARD_PINS_H_
 
 extern const unsigned char LOW;
 extern const unsigned char HIGH;

ard/serial.h

@@ -1,5 +1,5 @@
-#ifndef SERIAL_H_
-#define SERIAL_H_
+#ifndef ARD_SERIAL_H_
+#define ARD_SERIAL_H_
 
 void serial_init(unsigned int);
 void serial_write(char*, unsigned int);

ard/util.c

@@ -0,0 +1,5 @@
+#include "util.h"
+
+float map(float value, float fromLow, float fromHigh, float toLow, float toHigh){
+	return fromLow+((toHigh-toLow)/(fromHigh-fromLow))*(value-fromLow);
+}

ard/util.h

@@ -0,0 +1,6 @@
+#ifndef ARD_UTIL_H_
+#define ARD_UTIL_H_
+
+float map(float, float, float, float, float);
+
+#endif

compile

@@ -1,6 +1,7 @@
 #!/bin/bash
 
 mkdir build
+avr-gcc -Os -DF_CPU=16000000UL -mmcu=atmega328p -c -o build/util.o -Wall ard/util.c
 avr-gcc -Os -DF_CPU=16000000UL -mmcu=atmega328p -c -o build/serial.o -Wall ard/serial.c
 avr-gcc -Os -DF_CPU=16000000UL -mmcu=atmega328p -c -o build/pins.o -Wall ard/pins.c
 avr-gcc -Os -DF_CPU=16000000UL -mmcu=atmega328p -c -o build/main.o -Wall main.c

main.c

@@ -4,6 +4,7 @@
 #include <stdio.h>
 #include "ard/serial.h"
 #include "ard/pins.h"
+#include "ard/util.h"
 
 void prepare();
 void loop();
@@ -31,6 +32,7 @@ void prepare(){
 	pin_mode(A2, INPUT);*/
 
 	// PWM example
+	pin_mode(A1, INPUT);
 	pin_mode(3, OUTPUT);
 }
 
@@ -51,7 +53,12 @@ void loop(){
 	serial_write(out, 15);*/
 
 	// PWM example
-	digital_write(3, HIGH);
+	int analog = map(analog_read(A1), 0, 1023, 0, 255);
+	analog_write(3, analog);
+
+	char out[15];
+	sprintf(out, "%d", analog);
+	serial_write(out, 15);
 
 	_delay_ms(25);
 }