From ff979a918dad00eeb0f1f66034c347feedc2ec02 Mon Sep 17 00:00:00 2001
From: Daniel Friesel <derf@finalrewind.org>
Date: Sat, 18 Sep 2021 23:00:27 +0200
Subject: lora32u4ii: Add ADC driver

---
 include/arch/lora32u4ii/driver/adc.h  | 18 ++++++++++++++++++
 include/arch/lora32u4ii/driver/gpio.h | 11 ++++++++++-
 2 files changed, 28 insertions(+), 1 deletion(-)
 create mode 100644 include/arch/lora32u4ii/driver/adc.h

(limited to 'include/arch/lora32u4ii')

diff --git a/include/arch/lora32u4ii/driver/adc.h b/include/arch/lora32u4ii/driver/adc.h
new file mode 100644
index 0000000..5f9189a
--- /dev/null
+++ b/include/arch/lora32u4ii/driver/adc.h
@@ -0,0 +1,18 @@
+#ifndef ADC_H
+#define ADC_H
+
+class AVRADC {
+	private:
+		AVRADC(AVRADC const &copy);
+
+	public:
+		AVRADC() {}
+
+		int16_t getTemp_mdegC(int16_t offset = 205);
+		uint16_t getVCC_mV();
+		uint16_t getVBat_mV(bool controlCharger);
+};
+
+extern AVRADC adc;
+
+#endif
diff --git a/include/arch/lora32u4ii/driver/gpio.h b/include/arch/lora32u4ii/driver/gpio.h
index ba044d0..61dc867 100644
--- a/include/arch/lora32u4ii/driver/gpio.h
+++ b/include/arch/lora32u4ii/driver/gpio.h
@@ -3,6 +3,14 @@
 
 #include <avr/io.h>
 
+/*
+ * lora32u4ii v1.3 pin map:
+ *
+ * PB0 -> Charger and Vbat/2 measurement voltage divider enable
+ * PB5 -> User LED
+ * PB5 <- Vbat/2
+ */
+
 class GPIO {
 	private:
 		GPIO(const GPIO &copy);
@@ -40,7 +48,8 @@ class GPIO {
 		};
 
 		inline void setup() {
-			DDRB = _BV(PB5);
+			// PB5 is both output (user LED) and input (Vbat/2 to ADC).
+			// Leave it as input by default.
 		}
 		inline volatile uint8_t * pinToPort(uint8_t pin) {
 			if (pin <= pb7) {
-- 
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