added adc example

include/uart.h

@@ -14,7 +14,7 @@ void uart_init(uint16_t baud);
 
 uint8_t uart_read();
 
-void uart_read(uint8_t* buffer, size_t size);
+void uart_read_bytes(uint8_t* buffer, size_t size);
 
 void uart_write(uint8_t frame);
 

platformio.ini

@@ -14,6 +14,7 @@ board = nanoatmega328
 framework = arduino
 build_src_filter =
     +<*>
+    +*.c
     -<.git/>
     -<.svn/>
     -<blink/>
@@ -22,4 +23,5 @@ build_src_filter =
     -<trafficlight/>
     -<summer/>
     -<summer_controlled/>
-    +<uart/>
+    -<uart/>
+    +<adc/>

src/adc/adc.cpp

@@ -0,0 +1,50 @@
+//
+// Created by servostar on 09.12.23.
+//
+
+#include "adc.h"
+#include <stdlib.h>
+
+void adc_init() {
+    DDRC = 0x0;
+    SET_BIT(ADCSRA, ADEN); // enable ADC
+
+    // set prescaler / precision for conversion
+    SET_BIT(ADCSRA, ADPS0);
+    SET_BIT(ADCSRA, ADPS1);
+    SET_BIT(ADCSRA, ADPS2);
+
+    // set reference voltage
+    SET_BIT(ADMUX, REFS0);
+}
+
+uint16_t adc_read(uint8_t channel) {
+    ADMUX &= 0xF0;
+    ADMUX |= (channel & 0xF0);
+    // trigger adc conversion
+    ADCSRA |= (1 << ADSC);
+    // wait until converted
+    while((ADCSRA & (1 << ADIF)) == 0);
+    return ADCL + (ADCH << 8);
+}
+
+static uint16_t recent_adc = 0;
+
+void init() {
+    uart_init(9600);
+    adc_init();
+}
+
+void loop() {
+    uint16_t adc_val = adc_read(0);
+    char buf[10] = { 0 };
+    itoa(adc_val, buf, 10);
+
+    if (recent_adc != adc_val) {
+        recent_adc = adc_val;
+
+        uart_write_string("Channel 0: ");
+        uart_write_string(buf);
+        uart_write_string("\n");
+    }
+}

src/adc/adc.h

@@ -0,0 +1,13 @@
+//
+// Created by servostar on 09.12.23.
+//
+
+#ifndef ARDUINO_ADC_H
+#define ARDUINO_ADC_H
+
+#include "prelude.h"
+
+void init();
+void loop();
+
+#endif //ARDUINO_ADC_H

src/main.cpp

@@ -8,7 +8,8 @@ extern void loop();
 //#include "trafficlight/trafficlight.h"
 //#include "summer/summer.h"
 //#include "summer_controlled/summer.h"
-#include "uart/uart_read_write.h"
+//#include "uart/uart_read_write.h"
+#include "adc/adc.h"
 
 int main() {
     init();