From 50f8e1f2bb62b21a307e43f40005c365d315f0f9 Mon Sep 17 00:00:00 2001
From: Matthew Kennedy <matthewkennedy@outlook.com>
Date: Wed, 15 Nov 2023 20:28:51 -0800
Subject: [PATCH] auto-heat after 5 seconds of no CAN command #194

---
 firmware/sampling.cpp        | 14 ++++++++++++++
 firmware/sampling.h          |  5 +++++
 firmware/sampling_thread.cpp |  5 +++++
 firmware/util/timer.h        |  2 ++
 4 files changed, 26 insertions(+)

diff --git a/firmware/sampling.cpp b/firmware/sampling.cpp
index b055efa..c58887f 100644
--- a/firmware/sampling.cpp
+++ b/firmware/sampling.cpp
@@ -15,6 +15,11 @@ static const float lsu42TempValues[] = { 1199, 961, 857, 806, 775, 750, 730, 715
 static const float lsuAdvTempBins[]   = {   53,  96, 130, 162, 184, 206, 239, 278, 300, 330, 390, 462, 573, 730, 950, 1200, 1500, 1900, 2500, 3500, 5000, 6000 };
 static const float lsuAdvTempValues[] = { 1198, 982, 914, 875, 855, 838, 816, 794, 785, 771, 751, 732, 711, 691, 671,  653,  635,  614,  588,  562,  537,  528 };
 
+void Sampler::Init()
+{
+    m_startupTimer.reset();
+}
+
 float Sampler::GetNernstDc() const
 {
     return nernstDc;
@@ -36,10 +41,19 @@ float Sampler::GetPumpNominalCurrent() const
 
 float Sampler::GetInternalBatteryVoltage() const
 {
+#ifdef BATTERY_INPUT_DIVIDER
     // Dual HW can measure heater voltage for each channel
     // by measuring voltage on Heater- while FET is off
     // TODO: rename function?
     return internalBatteryVoltage;
+#else
+    // After 5 seconds, pretend that we get battery voltage.
+    // This makes the controller usable without CAN control
+    // enabling the heater - CAN message will be able to keep
+    // it disabled, but if no message ever arrives, this will
+    // start heating.
+    return m_startupTimer.hasElapsedSec(5) ? 13 : 0;
+#endif
 }
 
 float Sampler::GetSensorTemperature() const
diff --git a/firmware/sampling.h b/firmware/sampling.h
index 4bc7ddc..1b4c06e 100644
--- a/firmware/sampling.h
+++ b/firmware/sampling.h
@@ -1,5 +1,7 @@
 #pragma once
 
+#include "timer.h"
+
 struct ISampler
 {
     virtual float GetNernstDc() const = 0;
@@ -16,6 +18,7 @@ class Sampler : public ISampler
 {
 public:
     void ApplySample(AnalogChannelResult& result, float virtualGroundVoltageInt);
+    void Init();
 
     float GetNernstDc() const override;
     float GetNernstAc() const override;
@@ -32,6 +35,8 @@ private:
     float nernstDc = 0;
     float pumpCurrentSenseVoltage = 0;
     float internalBatteryVoltage = 0;
+
+    Timer m_startupTimer;
 };
 
 // Get the sampler for a particular channel
diff --git a/firmware/sampling_thread.cpp b/firmware/sampling_thread.cpp
index ca3458f..a4c7afe 100644
--- a/firmware/sampling_thread.cpp
+++ b/firmware/sampling_thread.cpp
@@ -46,6 +46,11 @@ static void SamplingThread(void*)
 
 void StartSampling()
 {
+    for (int i = 0; i < AFR_CHANNELS; i++)
+    {
+        samplers[i].Init();
+    }
+
     adcStart(&ADCD1, nullptr);
     chThdCreateStatic(waSamplingThread, sizeof(waSamplingThread), NORMALPRIO + 5, SamplingThread, nullptr);
 }
diff --git a/firmware/util/timer.h b/firmware/util/timer.h
index 2aeb258..0fa473a 100644
--- a/firmware/util/timer.h
+++ b/firmware/util/timer.h
@@ -1,5 +1,7 @@
 #pragma once
 
+#include <cstdint>
+
 /**
  * Helper class with "has X amount of time elapsed since most recent reset" methods
  * Brand new instances have most recent reset time far in the past, i.e. "hasElapsed" is true for any reasonable range