From 293c09cffaf7fb988f6341cc6bb39a37fdd4b32d Mon Sep 17 00:00:00 2001
From: "Ben V. Brown" <Ralim@Ralimtek.com>
Date: Thu, 6 May 2021 21:35:43 +1000
Subject: [PATCH] Add slew rate to the PID output for MHP

---
 source/Core/Inc/configuration.h   |  2 +-
 source/Core/Threads/PIDThread.cpp | 22 +++++++++++++++++-----
 2 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/source/Core/Inc/configuration.h b/source/Core/Inc/configuration.h
index f70f83b4..66f3f828 100644
--- a/source/Core/Inc/configuration.h
+++ b/source/Core/Inc/configuration.h
@@ -220,7 +220,7 @@
 #define MIN_BOOST_TEMP_C        150                     // The min settable temp for boost mode °C
 #define MIN_BOOST_TEMP_F        300                     // The min settable temp for boost mode °F
 #define NO_DISPLAY_ROTATE                               // Disable OLED rotation by accel
-
+#define SLEW_LIMIT              50                      // Limit to 3.0 Watts per 64ms pid loop update rate slew rate
 #endif
 
 #ifdef MODEL_TS100
diff --git a/source/Core/Threads/PIDThread.cpp b/source/Core/Threads/PIDThread.cpp
index 278de3a3..e8a69073 100644
--- a/source/Core/Threads/PIDThread.cpp
+++ b/source/Core/Threads/PIDThread.cpp
@@ -34,6 +34,9 @@ void startPIDTask(void const *argument __unused) {
                                               // be over-ridden rapidly
   pidTaskNotification    = xTaskGetCurrentTaskHandle();
   uint32_t PIDTempTarget = 0;
+#ifdef SLEW_LIMIT
+  int32_t x10WattsOutLast = 0;
+#endif
   for (;;) {
 
     if (ulTaskNotifyTake(pdTRUE, 2000)) {
@@ -109,12 +112,21 @@ void startPIDTask(void const *argument __unused) {
         x10WattsOut = 0;
       }
       if (systemSettings.powerLimit && x10WattsOut > (systemSettings.powerLimit * 10)) {
-        setTipX10Watts(systemSettings.powerLimit * 10);
-      } else if (powerSupplyWattageLimit && x10WattsOut > powerSupplyWattageLimit * 10) {
-        setTipX10Watts(powerSupplyWattageLimit * 10);
-      } else {
-        setTipX10Watts(x10WattsOut);
+        x10WattsOut = systemSettings.powerLimit * 10;
       }
+      if (powerSupplyWattageLimit && x10WattsOut > powerSupplyWattageLimit * 10) {
+        x10WattsOut = powerSupplyWattageLimit * 10;
+      }
+#ifdef SLEW_LIMIT
+      if (x10WattsOut - x10WattsOutLast > SLEW_LIMIT) {
+        x10WattsOut = x10WattsOutLast + SLEW_LIMIT;
+      }
+      if (x10WattsOut < 0) {
+        x10WattsOut = 0;
+      }
+      x10WattsOutLast = x10WattsOut;
+#endif
+      setTipX10Watts(x10WattsOut);
 #ifdef DEBUG_UART_OUTPUT
       log_system_state(x10WattsOut);
 #endif