AP_TemperatureSensor: add driver MCP9600

libraries/AP_TemperatureSensor/AP_TemperatureSensor.cpp

@@ -17,6 +17,7 @@
 
 #if AP_TEMPERATURE_SENSOR_ENABLED
 #include "AP_TemperatureSensor_TSYS01.h"
+#include "AP_TemperatureSensor_MCP9600.h"
 
 #include <AP_Logger/AP_Logger.h>
 #include <AP_Vehicle/AP_Vehicle_Type.h>
@@ -122,6 +123,11 @@ void AP_TemperatureSensor::init()
             case AP_TemperatureSensor::Type::TSYS01:
                 drivers[instance] = new AP_TemperatureSensor_TSYS01(*this, _state[instance], _params[instance]);
                 break;
+#endif
+#if AP_TEMPERATURE_SENSOR_MCP9600_ENABLED
+            case AP_TemperatureSensor::Type::MCP9600:
+                drivers[instance] = new AP_TemperatureSensor_MCP9600(*this, _state[instance], _params[instance]);
+                break;
 #endif
             case AP_TemperatureSensor::Type::NONE:
             default:

libraries/AP_TemperatureSensor/AP_TemperatureSensor.h

@@ -36,11 +36,13 @@
 // declare backend class
 class AP_TemperatureSensor_Backend;
 class AP_TemperatureSensor_TSYS01;
+class AP_TemperatureSensor_MCP9600;
 
 class AP_TemperatureSensor
 {
     friend class AP_TemperatureSensor_Backend;
     friend class AP_TemperatureSensor_TSYS01;
+    friend class AP_TemperatureSensor_MCP9600;
 
 public:
 
@@ -55,6 +57,7 @@ public:
     enum class Type : uint8_t {
         NONE                        = 0,
         TSYS01                      = 1,
+        MCP9600                     = 2,
     };
 
     // option to map to another system component

libraries/AP_TemperatureSensor/AP_TemperatureSensor_MCP9600.cpp

@@ -0,0 +1,141 @@
+/*
+ * Copyright (C) 2022  Kraus Hamdani Aerospace Inc. All rights reserved.
+ *
+ * This file is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This file is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Code by Tom Pittenger
+ */
+/*
+    Implements I2C driver for Microchip MCP9600 digital thermocouple EMF to Temperature converter
+*/
+
+#include "AP_TemperatureSensor_MCP9600.h"
+
+#if AP_TEMPERATURE_SENSOR_MCP9600_ENABLED
+
+#include <stdio.h>
+#include <AP_HAL/I2CDevice.h>
+#include <AP_Math/AP_Math.h>
+#include <GCS_MAVLink/GCS.h>
+
+extern const AP_HAL::HAL &hal;
+
+static const uint8_t MCP9600_CMD_HOT_JUNCT_TEMP     = 0x00;     // thermocoupler temp
+//static const uint8_t MCP9600_CMD_JUNCT_TEMP_DELTA   = 0x01;
+//static const uint8_t MCP9600_CMD_COLD_JUNCT_TEMP    = 0x02;     // ambient temp
+//static const uint8_t MCP9600_CMD_RAW_DATA_ADC       = 0x03;
+//static const uint8_t MCP9600_CMD_STATUS             = 0x04;
+static const uint8_t MCP9600_CMD_SENSOR_CFG         = 0x05;
+//static const uint8_t MCP9600_CMD_DEVICE_CFG         = 0x06;
+static const uint8_t MCP9600_CMD_DEVICE_ID_REV      = 0x20;     // to fetch WHOAMI
+
+
+static const uint8_t MCP9600_WHOAMI                 = 0x40;
+
+
+#define MCP9600_ADDR_LOW        0x60    // ADDR pin pulled low
+#define MCP9600_ADDR_HIGH       0x66    // ADDR pin pulled high
+
+#define AP_TemperatureSensor_MCP9600_UPDATE_INTERVAL_MS     500
+#define AP_TemperatureSensor_MCP9600_SCALE_FACTOR           (0.0625f)
+
+#ifndef AP_TemperatureSensor_MCP9600_ADDR_DEFAULT
+    #define AP_TemperatureSensor_MCP9600_ADDR_DEFAULT    MCP9600_ADDR_LOW
+#endif
+
+#ifndef AP_TemperatureSensor_MCP9600_ENFORCE_KNOWN_VALID_I2C_ADDRESS
+#define AP_TemperatureSensor_MCP9600_ENFORCE_KNOWN_VALID_I2C_ADDRESS 1
+#endif
+
+#ifndef AP_TemperatureSensor_MCP9600_Filter
+    #define AP_TemperatureSensor_MCP9600_Filter         2   // can be values 0 through 7 where 0 is no filtering (fast) and 7 is lots of smoothing (very very slow)
+#endif
+
+void AP_TemperatureSensor_MCP9600::init()
+{
+    constexpr char name[] = "MCP9600";
+
+#if AP_TemperatureSensor_MCP9600_ENFORCE_KNOWN_VALID_I2C_ADDRESS
+    // I2C Address: Default to using MCP9600_ADDR_LOW if it's out of range
+    if ((_params.bus_address < MCP9600_ADDR_LOW) || ( _params.bus_address > MCP9600_ADDR_HIGH)) {
+        printf("%s wrong I2C addr of 0x%2X, setting to 0x%2X. Reboot needed.", name, (unsigned)_params.bus_address.get(), (unsigned)MCP9600_ADDR_LOW);
+        _params.bus_address.set(MCP9600_ADDR_LOW);
+    }
+#endif
+
+    _dev = std::move(hal.i2c_mgr->get_device(_params.bus, _params.bus_address));
+    if (!_dev) {
+        printf("%s device is null!", name);
+        return;
+    }
+
+    WITH_SEMAPHORE(_dev->get_semaphore());
+
+    _dev->set_retries(10);
+
+    uint8_t buf[2];
+    if (!_dev->read_registers(MCP9600_CMD_DEVICE_ID_REV, buf, 2)) {
+        printf("%s failed to get WHOAMI", name);
+        return;
+    }
+    if (buf[0] != MCP9600_WHOAMI) {
+        printf("%s Got wrong WHOAMI: detected 0x%2X but expected 0x%2X", name, (unsigned)buf[0], (unsigned)MCP9600_WHOAMI);
+        return;
+    }
+    if (!set_config(ThermocoupleType::K, AP_TemperatureSensor_MCP9600_Filter)) {
+        printf("%s unable to configure", name);
+        return;
+    }
+
+#if 0
+    printf("%s Detected! Rev %u.%u on bus: %u addr: 0x%2X", name, (unsigned)(buf[1] >> 4), (unsigned)(buf[1] & 0x0F), (unsigned)_params.bus, (unsigned)_params.bus_address);
+#endif
+
+    // lower retries for run
+    _dev->set_retries(3);
+
+    /* Request 10Hz update */
+    _dev->register_periodic_callback(100 * AP_USEC_PER_MSEC,
+                                     FUNCTOR_BIND_MEMBER(&AP_TemperatureSensor_MCP9600::_timer, void));
+}
+
+void AP_TemperatureSensor_MCP9600::_timer()
+{
+    float temperature;
+    if (read_temperature(temperature)) {
+        set_temperature(temperature);
+    }
+}
+
+bool AP_TemperatureSensor_MCP9600::set_config(const ThermocoupleType thermoType, const uint8_t filter)
+{
+    const uint8_t data = (uint8_t)thermoType << 4 | (filter & 0x7);
+    if (!_dev->write_register(MCP9600_CMD_SENSOR_CFG, data)) {
+        return false;
+    }
+    return true;
+}
+
+bool AP_TemperatureSensor_MCP9600::read_temperature(float &temperature)
+{
+    uint8_t data[2];
+    if (!_dev->read_registers(MCP9600_CMD_HOT_JUNCT_TEMP, data, 2)) {
+        return false;
+    }
+
+    temperature = int16_t(UINT16_VALUE(data[0], data[1])) * AP_TemperatureSensor_MCP9600_SCALE_FACTOR;
+    return true;
+}
+#endif // AP_TEMPERATURE_SENSOR_MCP9600_ENABLED
+

libraries/AP_TemperatureSensor/AP_TemperatureSensor_MCP9600.h

@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2022  Kraus Hamdani Aerospace Inc. All rights reserved.
+ *
+ * This file is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This file is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Code by Tom Pittenger
+ */
+/*
+    Implements I2C driver for Microchip MCP9600 digital thermocouple EMF to Temperature converter
+*/
+
+#pragma once
+#include "AP_TemperatureSensor_Backend.h"
+
+#ifndef AP_TEMPERATURE_SENSOR_MCP9600_ENABLED
+    #define AP_TEMPERATURE_SENSOR_MCP9600_ENABLED AP_TEMPERATURE_SENSOR_ENABLED
+#endif
+
+#if AP_TEMPERATURE_SENSOR_MCP9600_ENABLED
+
+
+class AP_TemperatureSensor_MCP9600 : public AP_TemperatureSensor_Backend {
+    using AP_TemperatureSensor_Backend::AP_TemperatureSensor_Backend;
+public:
+
+    enum class ThermocoupleType : uint8_t {
+        K = 0,
+        J = 1,
+        T = 2,
+        N = 3,
+        S = 4,
+        E = 5,
+        B = 6,
+        R = 7,
+    };
+
+    void init(void) override;
+
+    void update(void) override {};
+
+private:
+
+    void _timer(void);
+
+    bool read_temperature(float &temperature);
+
+    bool set_config(const ThermocoupleType type, const uint8_t filter);
+};
+
+#endif // AP_TEMPERATURE_SENSOR_MCP9600_ENABLED

libraries/AP_TemperatureSensor/AP_TemperatureSensor_Params.cpp

@@ -42,7 +42,7 @@ const AP_Param::GroupInfo AP_TemperatureSensor_Params::var_info[] = {
     // @Param: TYPE
     // @DisplayName: Temperature Sensor Type
     // @Description: Enables temperature sensors
-    // @Values: 0:Disabled, 1:TSYS01
+    // @Values: 0:Disabled, 1:TSYS01, 2:MCP9600
     // @User: Standard
     // @RebootRequired: True
     AP_GROUPINFO_FLAGS("TYPE", 1, AP_TemperatureSensor_Params, type, AP_TEMPERATURE_SENSOR_TYPE_DEFAULT, AP_PARAM_FLAG_ENABLE),