added data logger

ESP32/.settings/language.settings.xml

@@ -5,7 +5,7 @@
 			<provider copy-of="extension" id="org.eclipse.cdt.ui.UserLanguageSettingsProvider"/>
 			<provider-reference id="org.eclipse.cdt.core.ReferencedProjectsLanguageSettingsProvider" ref="shared-provider"/>
 			<provider-reference id="org.eclipse.cdt.managedbuilder.core.MBSLanguageSettingsProvider" ref="shared-provider"/>
-			<provider class="org.eclipse.cdt.internal.build.crossgcc.CrossGCCBuiltinSpecsDetector" console="false" env-hash="-387635951242037682" id="org.eclipse.cdt.build.crossgcc.CrossGCCBuiltinSpecsDetector" keep-relative-paths="false" name="CDT Cross GCC Built-in Compiler Settings" parameter="${HOME}/.platformio/packages/toolchain-xtensa32/bin/xtensa-esp32-elf-g++ ${FLAGS} -std=gnu++11 -E -P -v -dD &quot;${INPUTS}&quot;" prefer-non-shared="true">
+			<provider class="org.eclipse.cdt.internal.build.crossgcc.CrossGCCBuiltinSpecsDetector" console="false" env-hash="1001601878207211985" id="org.eclipse.cdt.build.crossgcc.CrossGCCBuiltinSpecsDetector" keep-relative-paths="false" name="CDT Cross GCC Built-in Compiler Settings" parameter="${HOME}/.platformio/packages/toolchain-xtensa32/bin/xtensa-esp32-elf-g++ ${FLAGS} -std=gnu++11 -E -P -v -dD &quot;${INPUTS}&quot;" prefer-non-shared="true">
 				<language-scope id="org.eclipse.cdt.core.gcc"/>
 				<language-scope id="org.eclipse.cdt.core.g++"/>
 			</provider>
@@ -16,7 +16,7 @@
 			<provider copy-of="extension" id="org.eclipse.cdt.ui.UserLanguageSettingsProvider"/>
 			<provider-reference id="org.eclipse.cdt.core.ReferencedProjectsLanguageSettingsProvider" ref="shared-provider"/>
 			<provider-reference id="org.eclipse.cdt.managedbuilder.core.MBSLanguageSettingsProvider" ref="shared-provider"/>
-			<provider class="org.eclipse.cdt.internal.build.crossgcc.CrossGCCBuiltinSpecsDetector" console="false" env-hash="-387635951242037682" id="org.eclipse.cdt.build.crossgcc.CrossGCCBuiltinSpecsDetector" keep-relative-paths="false" name="CDT Cross GCC Built-in Compiler Settings" parameter="${HOME}/.platformio/packages/toolchain-xtensa32/bin/xtensa-esp32-elf-g++ ${FLAGS} -std=gnu++11 -E -P -v -dD &quot;${INPUTS}&quot;" prefer-non-shared="true">
+			<provider class="org.eclipse.cdt.internal.build.crossgcc.CrossGCCBuiltinSpecsDetector" console="false" env-hash="1001601878207211985" id="org.eclipse.cdt.build.crossgcc.CrossGCCBuiltinSpecsDetector" keep-relative-paths="false" name="CDT Cross GCC Built-in Compiler Settings" parameter="${HOME}/.platformio/packages/toolchain-xtensa32/bin/xtensa-esp32-elf-g++ ${FLAGS} -std=gnu++11 -E -P -v -dD &quot;${INPUTS}&quot;" prefer-non-shared="true">
 				<language-scope id="org.eclipse.cdt.core.gcc"/>
 				<language-scope id="org.eclipse.cdt.core.g++"/>
 			</provider>

ESP32/src/DataLogger.cpp

@@ -0,0 +1,84 @@
+#include "DataLogger.h"
+
+#include "utils.h"
+
+#include <Preferences.h>
+
+DataLogger DataLogger::mainLogger;
+
+DataLogger::DataLogger()
+{
+}
+
+DataLogger::~DataLogger()
+{
+}
+
+void DataLogger::open()
+{
+	if(isOpen()) return;
+
+	lastLogTime = -std::numeric_limits<float>::max();
+	currentTime = 0.0f;
+
+	Preferences preferences;
+	preferences.begin("vm-log", false);
+	uint16_t logFileIndex = preferences.getUShort("next", 1);
+	preferences.putUShort("next", logFileIndex + 1);
+	preferences.end();
+
+	// clear existing files until we have enough free space
+	const size_t requiredSpace = 300000; // in bytes
+	size_t totalSpace = SPIFFS.totalBytes();
+	auto logFolder = SPIFFS.open("/log");
+	auto file = logFolder.openNextFile();
+	while(file && SPIFFS.usedBytes() + requiredSpace > totalSpace)
+	{
+		Serial.print("Deleting old log file: ");
+		Serial.println(file.name());
+
+		SPIFFS.remove(file.name());
+		file = logFolder.openNextFile();
+	}
+
+	char fileName[32];
+	sprintf(fileName, "/log/L%05d.csv", logFileIndex);
+
+	file = SPIFFS.open(fileName, FILE_WRITE);
+	if(!file) Serial.println("DataLogger: failed to open file");
+
+	if(!file.print("time,speed,battery voltage,battery output current\n")) Serial.println("DataLogger: failed to write to file");
+}
+
+void DataLogger::close()
+{
+	if(!isOpen()) return;
+	file.close();
+}
+
+void DataLogger::log(unsigned long timeMilliseconds, const Entry& entry)
+{
+	if(lastLogTime == -std::numeric_limits<float>::max()) lastTimeMilliseconds = timeMilliseconds;
+	currentTime += (float)utils::elapsed(lastTimeMilliseconds, timeMilliseconds) / 1000.0f;
+	lastTimeMilliseconds = timeMilliseconds;
+
+	if((lastEntry.isDifferent(entry) || currentTime >= lastLogTime + 20.0f) && currentTime >= lastLogTime + 0.2f)
+	{
+		char line[128];
+		sprintf(line, "%.3f,%.3f,%.3f,%.3f\n", currentTime, entry.speed, entry.batteryVoltage, entry.batteryOutputCurrent);
+		file.print(line);
+
+		lastEntry = entry;
+		lastLogTime = currentTime;
+	}
+}
+
+bool DataLogger::isOpen()
+{
+	return file;
+}
+
+const char* DataLogger::currentLogFileName()
+{
+	return isOpen() ? file.name() : "";
+}

ESP32/src/DataLogger.h

@@ -0,0 +1,45 @@
+#include <cmath>
+#include <SPIFFS.h>
+
+class DataLogger
+{
+public:
+	struct Entry
+	{
+		float batteryVoltage = 0.0f; // V
+		float batteryOutputCurrent = 0.0f; // A
+		float speed = 0.0f; // m/s
+
+		bool isDifferent(const Entry& other)
+		{
+			const float scale = speed > 0.0f ? 1.0f : 5.0f;
+			return
+				   std::abs(batteryVoltage - other.batteryVoltage) > 0.1f * scale
+				&& std::abs(batteryOutputCurrent - other.batteryOutputCurrent) > 0.1f * scale
+				&& std::abs(speed - other.speed) > 0.1f;
+		}
+	};
+
+public:
+	DataLogger();
+	~DataLogger();
+
+	static DataLogger& get() { return mainLogger; }
+
+	void open();
+	void close();
+	void log(unsigned long timeMilliseconds, const Entry& entry);
+
+	bool isOpen();
+	const char* currentLogFileName();
+
+private:
+	static DataLogger mainLogger;
+
+	Entry lastEntry;
+	unsigned long lastTimeMilliseconds = -1;
+	float currentTime = 0.0f;
+	float lastLogTime = 0.0f;
+
+	File file; // @suppress("Abstract class cannot be instantiated")
+};

ESP32/src/utils.cpp

@@ -0,0 +1,19 @@
+#include "utils.h"
+
+namespace utils
+{
+	unsigned long elapsed(unsigned long from, unsigned long to)
+	{
+		if(to >= from)
+		{
+			return to - from;
+		}
+		else
+		{
+			// if the counter overflowed, this computes the real duration
+			// of course it won't work if the counter made a "full turn" or more
+			const unsigned long biggestValue = (unsigned long)-1;
+			return (biggestValue - from) + to + 1;
+		}
+	}
+}

ESP32/src/utils.h

@@ -0,0 +1,4 @@
+namespace utils
+{
+	unsigned long elapsed(unsigned long from, unsigned long to);
+}

ESP32/src/vehicle-monitor.cpp

@@ -9,9 +9,13 @@
 
 #include "ADC.h"
 #include "OTA.h"
+#include "DataLogger.h"
+#include "utils.h"
 
 #include "wifi-credentials.h"
 
+#define DUMMY_DATA 0
+
 AsyncWebServer server(80);
 
 ADC currentSensor(36);
@@ -24,13 +28,15 @@ const int numImpulsesPerTurn = 2;
 const float wheelCircumferenceMeters = wheelDiameterInches * 0.0254f * 3.1415f / (float)numImpulsesPerTurn;
 
 uint16_t batteryVoltage = 0; // in mV
-uint16_t batteryCurrent = 0; // in mV
+uint16_t batteryOutputCurrent = 0; // in mV
 
 WiFiMulti wifiMulti;
 wl_status_t wifi_STA_status = WL_NO_SHIELD;
 unsigned long wifiConnexionBegin = 0;
 const unsigned long retryWifiConnexionDelay = 60000; // in milliseconds
 
+unsigned long stoppedSince = -1;
+
 volatile bool debugLedState = true;
 
 volatile bool speedSensorState = false;
@@ -51,13 +57,13 @@ void IRAM_ATTR onSpeedSensorChange(bool newState)
 	}
 	else
 	{
-		unsigned long impulseDuration = now > speedSensorRiseTime ? now - speedSensorRiseTime : (4294967295 - speedSensorRiseTime) + now; // if now is lower than speedSensorRiseTime, it means millis() has overflowed (happens every 50 days)
+		unsigned long impulseDuration = utils::elapsed(speedSensorRiseTime, now);
 		if(impulseDuration > 1000) return; // impulse was too long, ignore it (maybe magnet stopped near the sensor)
 
 		debugLedState = !debugLedState;
 		digitalWrite(debugLedPin, debugLedState ? HIGH : LOW);
 
-		unsigned long timeSinceLastImpulse = now > speedSensorLastImpulseTime ? now - speedSensorLastImpulseTime : (4294967295 - speedSensorLastImpulseTime) + now;
+		unsigned long timeSinceLastImpulse = utils::elapsed(speedSensorLastImpulseTime, now);
 		speedSensorLastImpulseTime = now;
 		if(timeSinceLastImpulse > 30 && timeSinceLastImpulse < 4000)
 		{
@@ -74,11 +80,21 @@ void IRAM_ATTR onSpeedSensorChange() { onSpeedSensorChange(digitalRead(speedSens
 
 float getSpeed()
 {
+	#if DUMMY_DATA
+	{
+		float result = max(0.0f, sinf((float)millis()/30000.0f)) * 7.0f;
+		return result < 0.25f ? 0.0f : result;
+	}
+	#endif
+
 	unsigned long now = millis();
 
+	noInterrupts();
 	unsigned long lastImpulseInterval = speedSensorLastImpulseInterval;
 	unsigned long lastImpulseTime = speedSensorLastImpulseTime;
-	unsigned long timeSinceLastImpulse = now > lastImpulseTime ? now - lastImpulseTime : (4294967295 - lastImpulseTime) + now;
+	interrupts();
+
+	unsigned long timeSinceLastImpulse = utils::elapsed(lastImpulseTime, now);
 
 	unsigned long interval = timeSinceLastImpulse > lastImpulseInterval * 10 / 9 ? timeSinceLastImpulse : lastImpulseInterval;
 
@@ -144,18 +160,52 @@ void setup()
 
 	server.on("/api/status", HTTP_GET, [](AsyncWebServerRequest *request){
 		int v = batteryVoltage;
-		int c = batteryCurrent;
+		int c = batteryOutputCurrent;
 		int s = (int)(getSpeed() * 1000.0f + 0.5f);
 
+		const char* logFileName = DataLogger::get().currentLogFileName();
+		if(String(logFileName).startsWith("/log/")) logFileName += 5;
+
+		int totalSize = (int)(SPIFFS.totalBytes() / 1000);
+		int usedSize = (int)(SPIFFS.usedBytes() / 1000);
+
 		char json[128];
-		sprintf(json, "{\"v\":%d,\"c\":%d,\"s\":%d}", v, c, s);
+		sprintf(json, "{\"v\":%d,\"c\":%d,\"s\":%d,\"log\":\"%s\",\"tot\":%d,\"used\":%d}", v, c, s, logFileName, totalSize, usedSize);
 		request->send(200, "text/json", json);
 	});
 
+	server.on("/api/log/list", HTTP_GET, [](AsyncWebServerRequest *request){
+		String json;
+
+		json = "{\"files\":[";
+
+		auto logFolder = SPIFFS.open("/log");
+		auto file = logFolder.openNextFile();
+		bool first = true;
+		while(file)
+		{
+			if(!first) json += ",";
+			json += "{\"n\":\"/api";
+			json += file.name();
+			json += "\",\"s\":";
+			json += file.size();
+			json += "}";
+
+			first = false;
+			file = logFolder.openNextFile();
+		}
+
+		json += "]}";
+		request->send(200, "text/json", json.c_str());
+	});
+
 	// Special case to send index.html without caching
 	server.on("/", HTTP_GET, [](AsyncWebServerRequest *request){ request->send(SPIFFS, "/www/index.html", "text/html"); });
 	server.serveStatic("/index.html", SPIFFS, "/www/index.html");
 
+	// Log files (not cached)
+	server.serveStatic("/api/log", SPIFFS, "/log/");
+
 	// Other static files are cached (index.html knows whether to ignore caching or not for each file)
 	server.serveStatic("/", SPIFFS, "/www/").setCacheControl("max-age=5184000");
 
@@ -163,10 +213,8 @@ void setup()
 	Serial.println("HTTP server started");
 }
 
-void loop()
+void handle_wifi_connection()
 {
-	OTA.handle();
-
 	wl_status_t newWifiStatus = WiFi.status();
 	if(newWifiStatus != wifi_STA_status)
 	{
@@ -201,11 +249,14 @@ void loop()
 	if(wifi_STA_status != WL_CONNECTED)
 	{
 		unsigned long now = millis();
-		unsigned long elapsed = now > wifiConnexionBegin ? now - wifiConnexionBegin : (4294967295 - wifiConnexionBegin) + now;
+		unsigned long elapsed = utils::elapsed(wifiConnexionBegin, now);
 		if(elapsed > retryWifiConnexionDelay)
 			connectWifi();
 	}
+}
 
+void handle_ADC_measures()
+{
 	const int numSamples = 100;
 
 	float averageV = 0.0f;
@@ -228,9 +279,49 @@ void loop()
 	averageV *= 27.000f; // account for voltage divider to retrieve the input voltage
 	averageC = max(0.0f, averageC - 2.5f) / 0.0238f; // convert voltage to current, according to the sensor linear relation
 
-	// TODO: mutex ?
 	batteryVoltage = (uint16_t)(averageV * 1000.0f + 0.5f);
-	batteryCurrent = (uint16_t)(averageC * 1000.0f + 0.5f);
+	batteryOutputCurrent = (uint16_t)(averageC * 1000.0f + 0.5f);
+
+	#if DUMMY_DATA
+	batteryVoltage = (uint16_t)((float)random(4000, 4020) / 100.0f * 1000.0f + 0.5f);
+	batteryOutputCurrent = (uint16_t)(max(0.0f, sinf((float)millis()/30000.0f)) * 25.0f * 1000.0f + 0.5f);
+	#endif
+}
+
+void loop()
+{
+	OTA.handle();
+	handle_wifi_connection();
+	handle_ADC_measures();
+
+	unsigned long now = millis();
+	static DataLogger::Entry entry;
+	entry.batteryVoltage = (float)batteryVoltage / 1000.0f;
+	entry.batteryOutputCurrent = (float)batteryOutputCurrent / 1000.0f;
+	entry.speed = getSpeed();
+
+	if(entry.speed > 0.0f)
+	{
+		stoppedSince = -1;
+		if(!DataLogger::get().isOpen())
+		{
+			Serial.println("Starting DataLogger");
+			DataLogger::get().open();
+		}
+	}
+	else
+	{
+		if(stoppedSince == -1)
+		{
+			stoppedSince = now;
+		}
+		else if(utils::elapsed(stoppedSince, now) > 5 * 60 * 1000)
+		{
+			Serial.println("Stopping DataLogger");
+			DataLogger::get().close();
+		}
+	}
+	DataLogger::get().log(now, entry);
 
 	delay(10);
 }