From 4281e89e5d7505c079bf49070554a26643ffe186 Mon Sep 17 00:00:00 2001
From: Alex Voinea <voinea.dragos.alexandru@gmail.com>
Date: Mon, 12 Jul 2021 17:42:32 +0300
Subject: [PATCH] HAL adc

---
 src/hal/adc.cpp | 24 +++++++++++++++++++++++-
 src/hal/adc.h   |  3 ++-
 src/main.cpp    |  2 +-
 3 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/src/hal/adc.cpp b/src/hal/adc.cpp
index 5089d7d..731a486 100644
--- a/src/hal/adc.cpp
+++ b/src/hal/adc.cpp
@@ -1,9 +1,31 @@
 #include "adc.h"
+#include <avr/io.h>
 
 namespace hal {
 namespace adc {
 
-uint16_t ReadADC(uint8_t adc) { return 0; }
+void Init() {
+    ADCSRA |= (1 << ADPS2) | (1 << ADPS1) | (1 << ADPS0);
+	ADMUX |= (1 << REFS0);
+    ADCSRA |= (1 << ADEN);
+}
+
+uint16_t ReadADC(uint8_t channel) { 
+    uint8_t admux = ADMUX;
+    admux &= ~0x1F;
+    admux |= channel & 0x07;
+    ADMUX = admux;
+
+    uint8_t adcsrb = ADCSRB;
+    adcsrb &= ~(1 << MUX5);
+    adcsrb |= (channel & 0x08) << 1;
+    ADCSRB = adcsrb;
+
+    ADCSRA |= (1 << ADSC);
+    while (ADCSRA & (1 << ADSC));
+
+    return ADC;
+ }
 
 } // namespace adc
 } // namespace hal
diff --git a/src/hal/adc.h b/src/hal/adc.h
index 9116dff..26029d3 100644
--- a/src/hal/adc.h
+++ b/src/hal/adc.h
@@ -7,7 +7,8 @@ namespace hal {
 namespace adc {
 
 /// ADC access routines
-uint16_t ReadADC(uint8_t adc);
+void Init();
+uint16_t ReadADC(uint8_t channel);
 
 } // namespace adc
 } // namespace hal
diff --git a/src/main.cpp b/src/main.cpp
index 27c5d5b..d63635c 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -137,7 +137,7 @@ void setup() {
     ml::leds.SetMode(1, ml::Color::green, ml::Mode::on);
     ml::leds.Step();
 
-    // adc::Init();
+    adc::Init();
     ml::leds.SetMode(0, ml::Color::green, ml::Mode::on);
     ml::leds.Step();
 }