Example CAN Project integrated

esp32/include/ControllerConfiguration.h

@@ -82,6 +82,9 @@
 #endif
 #ifdef ANALOG_WATER
 #define SENSOR_TANK_ANALOG     ANALOG_WATER /**< GPIO 34 - analog water sensor (GPIO_NUM_34) */ 
+/* Define CAN communication via I2C Connector */
+#define CAN_TX		GPIO_NUM_17 /**< GPIO 17 - water sensor SDA */ 
+#define CAN_RX		GPIO_NUM_16 /**< GPIO 16 - water sensor SCL */
 #else
 #ifdef HWREVISION07
 

esp32/include/can.h

@@ -0,0 +1,14 @@
+/**
+ * @file can.h
+ * 
+ */
+
+#include "ControllerConfiguration.h"
+
+#ifndef PLANTCTRL_CAN_H
+#define PLANTCTRL_CAN_H
+
+void can_setup(void);
+void can_loop(void);
+
+#endif

esp32/platformio.ini

@@ -22,18 +22,11 @@ build_flags = -DPIO_FRAMEWORK_ARDUINO_LWIP2_LOW_MEMORY
 	-DPLANT6_SENSORTYPE=FREQUENCY_MOD_RESISTANCE_PROBE
 	-DTIMED_LIGHT_PIN=CUSTOM1_PIN5
 	-DANALOG_WATER=GPIO_NUM_34
-    ; Optional: Compatibilitymode for hardware revision 0.7
-    ;-DHWREVISION07=1
-
 board_build.partitions = defaultWithSmallerSpiffs.csv
-
+lib_deps = 
-;#https://docs.espressif.com/projects/esp-idf/en/latest/esp32/api-guides/partition-tables.html
+	bblanchon/ArduinoJson@^6.20.1
-
-
-; the latest development brankitchen-lightch (convention V3.0.x) 
-lib_deps = bblanchon/ArduinoJson@^6.20.1
 	paulstoffregen/OneWire@^2.3.6
 	milesburton/DallasTemperature@^3.11.0
 	pololu/VL53L0X@^1.3.1
 	https://github.com/homieiot/homie-esp8266.git#develop
-
+	handmade0octopus/ESP32-TWAI-CAN@^1.0.1

esp32/src/can.cpp

@@ -0,0 +1,83 @@
+/**
+ * @file can.cpp
+ * 
+ * Based on ESP32-TWAI-CAN example
+ */
+
+#include <ESP32-TWAI-CAN.hpp>
+#include "can.h"
+
+#ifndef CAN_TX
+#error CAN Interface not declared
+#else
+
+CanFrame rxFrame;
+
+void sendObdFrame(uint8_t obdId) {
+	CanFrame obdFrame = { 0 };
+	obdFrame.identifier = 0x7DF; // Default OBD2 address;
+	obdFrame.extd = 0;
+	obdFrame.data_length_code = 8;
+	obdFrame.data[0] = 2;
+	obdFrame.data[1] = 1;
+	obdFrame.data[2] = obdId;
+	obdFrame.data[3] = 0xAA;    // Best to use 0xAA (0b10101010) instead of 0
+	obdFrame.data[4] = 0xAA;    // CAN works better this way as it needs
+	obdFrame.data[5] = 0xAA;    // to avoid bit-stuffing
+	obdFrame.data[6] = 0xAA;
+	obdFrame.data[7] = 0xAA;
+    // Accepts both pointers and references 
+    ESP32Can.writeFrame(obdFrame);  // timeout defaults to 1 ms
+}
+
+void can_setup() {
+    // Setup serial for debbuging.
+    Serial.begin(115200);
+
+    // Set pins
+	ESP32Can.setPins(CAN_TX, CAN_RX);
+	
+    // You can set custom size for the queues - those are default
+    ESP32Can.setRxQueueSize(5);
+	ESP32Can.setTxQueueSize(5);
+
+    // .setSpeed() and .begin() functions require to use TwaiSpeed enum,
+    // but you can easily convert it from numerical value using .convertSpeed()
+    ESP32Can.setSpeed(ESP32Can.convertSpeed(500));
+
+    // You can also just use .begin()..
+    if(ESP32Can.begin()) {
+        Serial.println("CAN bus started!");
+    } else {
+        Serial.println("CAN bus failed!");
+    }
+
+    // or override everything in one command;
+    // It is also safe to use .begin() without .end() as it calls it internally
+    if(ESP32Can.begin(ESP32Can.convertSpeed(500), CAN_TX, CAN_RX, 10, 10)) {
+        Serial.println("CAN bus started!");
+    } else {
+        Serial.println("CAN bus failed!");
+    }
+}
+
+void can_loop() {
+    static uint32_t lastStamp = 0;
+    uint32_t currentStamp = millis();
+    
+    if(currentStamp - lastStamp > 1000) {   // sends OBD2 request every second
+        lastStamp = currentStamp;
+        sendObdFrame(5); // For coolant temperature
+    }
+
+    // You can set custom timeout, default is 1000
+    if(ESP32Can.readFrame(rxFrame, 1000)) {
+        // Comment out if too many frames
+        Serial.printf("Received frame: %03X  \r\n", rxFrame.identifier);
+        if(rxFrame.identifier == 0x7E8) {   // Standard OBD2 frame responce ID
+            Serial.printf("Collant temp: %3d°C \r\n", rxFrame.data[3] - 40); // Convert to °C
+        }
+    }
+}
+
+#endif

esp32/src/main.cpp

@@ -38,6 +38,7 @@
 #include "MQTTUtils.h"
 #include "esp_ota_ops.h"
 #include "Arduino.h"
+#include "can.h"
 
 extern "C" bool verifyRollbackLater(){
     return true;
@@ -964,6 +965,7 @@ void safeSetup()
     Serial.println("Initial Setup. Start Accesspoint...");
     vmDownloadMode = true;
   }
+  can_setup();
   stayAlive.advertise("alive").setName("Alive").setDatatype(NUMBER_TYPE).settable(aliveHandler);
   setupFinishedTimestamp = millis();
 }
@@ -1078,6 +1080,8 @@ void loop()
   {
     pumpActiveLoop();
   }
+
+  can_loop();
 }
 
 /***