From 985484179bf8a520dc934d47154df00df1f34663 Mon Sep 17 00:00:00 2001
From: David Lenfesty <6893214+davidlenfesty@users.noreply.github.com>
Date: Fri, 25 Oct 2019 13:26:23 -0600
Subject: [PATCH] Added diode calibration

---
 lab_3/main.c | 10 +++++-----
 lab_3/main.h |  4 ++--
 2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/lab_3/main.c b/lab_3/main.c
index e1cbb56..4ca0c2d 100755
--- a/lab_3/main.c
+++ b/lab_3/main.c
@@ -66,16 +66,16 @@ uint16_t adc_run_conversion(uint8_t adc_selection) {
 /** @brief Converts an ADC value from a measurement on an LM35 into a temperature.
  */
 int8_t lm35_convert(uint16_t adc_reading) {
-    return (float) (adc_reading * ADC_VREF / ADC_RESOLUTION) / LM35_SENSITIVITY;
+    return (adc_reading * ADC_VREF / ADC_RESOLUTION) / LM35_SENSITIVITY;
 }
 
 /** @brief Converts and ADC value from a measurement on a diode into a temperature.
- * TODO
  */
 int8_t diode_convert(uint16_t adc_reading) {
-    // Do some funky math here
-	
-    return 0;
+	// This could be collapsed but it doesn't really matter
+	int16_t value_diff = adc_reading - DIODE_VALUE_25C;
+	int16_t temp_diff = value_diff / DIODE_SENSITIVITY;
+    return temp_diff + 25;
 }
 
 int main() {
diff --git a/lab_3/main.h b/lab_3/main.h
index d7a5c87..a1e001a 100644
--- a/lab_3/main.h
+++ b/lab_3/main.h
@@ -13,8 +13,8 @@
 #define ADC_VREF            1.1
 #define ADC_RESOLUTION      1023 // (2^ 10 - 1, 10 bits resolution)
 
-#define DIODE_VALUE_0C		 // ADC value for diode at 0C
-#define DIODE_SENSITIVITY	0.0025 // V / degree C, tuneable
+#define DIODE_VALUE_25C		436 // ADC value for diode at 0C
+#define DIODE_SENSITIVITY	-1.85 // ADC value / degree C, tuneable
 
 #define LM35_SENSITIVITY    0.01 // V / degree C, see LM35 datasheet