From 6f591ab2f7244db52a0403439053fc478e65aedf Mon Sep 17 00:00:00 2001
From: Thomas Kolb <thomas@tkolb.de>
Date: Thu, 3 Oct 2019 01:46:05 +0200
Subject: [PATCH] Added a thermal shutdown state

---
 src/main.c | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/src/main.c b/src/main.c
index 4b13f8c..b9d5d3b 100644
--- a/src/main.c
+++ b/src/main.c
@@ -34,6 +34,7 @@ enum OperState {
 	ConvFloat,
 	ConvConstCurrent,
 	ConvMPP,
+	ThermalShutdown,
 	Idle,
 };
 
@@ -614,6 +615,10 @@ int main(void)
 	fxp_t ADC2CURRENT_M = fxp_from_float( 0.00225f);
 	fxp_t ADC2CURRENT_T = fxp_from_float(-0.2255f);
 
+	// Thermal shutdown thresholds
+	fxp_t SHUTDOWN_TEMPERATURE = fxp_from_float(55.0f);
+	fxp_t RECOVER_TEMPERATURE = fxp_from_float(45.0f);
+
 	/* if power changes by more than this factor, MPP is tested again */
 	MPP_MAX_POWER_CHANGE_FACTOR = fxp_from_float(0.2f);
 
@@ -1041,6 +1046,16 @@ int main(void)
 
 					break;
 
+				case ThermalShutdown:
+					// shut down the converter
+					timer_set_oc_value(TIM1, TIM_CH_CONV, 0);
+
+					if(power_state.temp_avg < RECOVER_TEMPERATURE) {
+						nextState = ConvMPP;
+						operState = Bootstrap;
+					}
+					break;
+
 				default:
 					debug_send_string("Invalid state detected!");
 					sentSomething = 1;
@@ -1049,6 +1064,10 @@ int main(void)
 					break;
 			}
 
+			if(power_state.temp_avg > SHUTDOWN_TEMPERATURE) {
+				operState = ThermalShutdown;
+			}
+
 			if(operState != lastState) {
 				time_in_state = 0;
 				lastState = operState;
@@ -1073,6 +1092,9 @@ int main(void)
 					case ConvMPP:
 						lcd_send_string("MPP");
 						break;
+					case ThermalShutdown:
+						lcd_send_string("TRM");
+						break;
 					default:
 						lcd_send_string("???");
 						break;