AP_Compass: added backend implementation for RM3100 compass

libraries/AP_Compass/AP_Compass.cpp

@@ -23,6 +23,7 @@
 #endif
 #include "AP_Compass_MMC3416.h"
 #include "AP_Compass_MAG3110.h"
+#include "AP_Compass_RM3100.h"
 #include "AP_Compass.h"
 #include "Compass_learn.h"
 

libraries/AP_Compass/AP_Compass.h

@@ -379,6 +379,7 @@ private:
         DRIVER_SITL     =13,
         DRIVER_MAG3110  =14,
         DRIVER_IST8308  = 15,
+		DRIVER_RM3100   =16,
     };
 
     bool _driver_enabled(enum DriverType driver_type);

libraries/AP_Compass/AP_Compass_Backend.h

@@ -58,6 +58,7 @@ public:
         DEVTYPE_MAG3110  = 0x0E,
         DEVTYPE_SITL  = 0x0F,
         DEVTYPE_IST8308 = 0x10,
+		DEVTYPE_RM3100 = 0x11,
     };
 
 

libraries/AP_Compass/AP_Compass_RM3100.cpp

@@ -0,0 +1,253 @@
+/*
+ * 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/>.
+ */
+/*
+  Driver by Thomas Schumacher, Jan 2019
+  Structure based on LIS3MDL driver
+
+ */
+#include "AP_Compass_RM3100.h"
+
+#include <AP_HAL/AP_HAL.h>
+#include <utility>
+#include <AP_Math/AP_Math.h>
+#include <stdio.h>
+
+#define RM3100_POLL_REG        0x00
+
+#define RM3100_CMM_REG         0x01
+
+#define RM3100_CCX1_REG        0x04
+#define RM3100_CCX0_REG        0x05
+#define RM3100_CCY1_REG        0x06
+#define RM3100_CCY0_REG        0x07
+#define RM3100_CCZ1_REG        0x08
+#define RM3100_CCZ0_REG        0x09
+
+#define RM3100_TMRC_REG        0x0B
+
+#define RM3100_MX2_REG      0x24
+#define RM3100_MX1_REG      0x25
+#define RM3100_MX0_REG      0x26
+#define RM3100_MY2_REG      0x27
+#define RM3100_MY1_REG      0x28
+#define RM3100_MY0_REG      0x29
+#define RM3100_MZ2_REG      0x2A
+#define RM3100_MZ1_REG      0x2B
+#define RM3100_MZ0_REG      0x2C
+
+#define RM3100_BIST_REG       0x33
+#define RM3100_STATUS_REG     0x34
+#define RM3100_HSHAKE_REG     0x34
+#define RM3100_REVID_REG      0x36
+
+#define CCP0    0xC8      // Default Cycle Count
+#define CCP1    0x00
+#define GAIN_CC50 20.0f   // LSB/uT
+#define GAIN_CC100 38.0f
+#define GAIN_CC200 75.0f
+#define UTESLA_TO_MGAUSS   10.0f // uT to mGauss conversion
+
+#define TMRC    0x94    // Update rate 150Hz
+#define CMM     0x71    // read 3 axes and set data ready if 3 axes are ready
+
+extern const AP_HAL::HAL &hal;
+
+AP_Compass_Backend *AP_Compass_RM3100::probe(Compass &compass,
+                                              AP_HAL::OwnPtr<AP_HAL::Device> dev,
+                                              bool force_external,
+                                              enum Rotation rotation)
+{
+    if (!dev) {
+        return nullptr;
+    }
+    AP_Compass_RM3100 *sensor = new AP_Compass_RM3100(compass, std::move(dev), force_external, rotation);
+    if (!sensor || !sensor->init()) {
+        delete sensor;
+        return nullptr;
+    }
+
+    return sensor;
+}
+
+AP_Compass_RM3100::AP_Compass_RM3100(Compass &compass,
+                                       AP_HAL::OwnPtr<AP_HAL::Device> _dev,
+                                       bool _force_external,
+                                       enum Rotation _rotation)
+    : AP_Compass_Backend(compass)
+    , dev(std::move(_dev))
+    , force_external(_force_external)
+    , rotation(_rotation)
+{
+}
+
+bool AP_Compass_RM3100::init()
+{
+    if (!dev->get_semaphore()->take(HAL_SEMAPHORE_BLOCK_FOREVER)) {
+        return false;
+    }
+
+    // high retries for init
+    dev->set_retries(10);
+
+    // maybe add a test for revision id value here and goto fail if not correct
+    // it is not clear if revision id is the same for all compasses, in the same manner as a whoami
+
+    dev->setup_checked_registers(8);
+
+    dev->write_register(RM3100_TMRC_REG, TMRC, true); // cycle count z
+    dev->write_register(RM3100_CMM_REG, CMM, false); // CMM configuration
+    dev->write_register(RM3100_CCX1_REG, CCP1, true); // cycle count x
+    dev->write_register(RM3100_CCX0_REG, CCP0, true); // cycle count x
+    dev->write_register(RM3100_CCY1_REG, CCP1, true); // cycle count y
+    dev->write_register(RM3100_CCY0_REG, CCP0, true); // cycle count y
+    dev->write_register(RM3100_CCZ1_REG, CCP1, true); // cycle count z
+    dev->write_register(RM3100_CCZ0_REG, CCP0, true); // cycle count z
+
+    _scaler = (1 / GAIN_CC200) * UTESLA_TO_MGAUSS; // has to be changed if using a different cycle count
+
+    // lower retries for run
+    dev->set_retries(3);
+    
+    dev->get_semaphore()->give();
+
+    /* register the compass instance in the frontend */
+    compass_instance = register_compass();
+
+    printf("Found a RM3100 at address 0x%x as compass %u\n", dev->get_bus_address(), compass_instance);
+    
+    set_rotation(compass_instance, rotation);
+
+    if (force_external) {
+        set_external(compass_instance, true);
+    }
+    
+    dev->set_device_type(DEVTYPE_RM3100);
+    set_dev_id(compass_instance, dev->get_bus_id());
+
+    // call timer() at 80Hz
+    dev->register_periodic_callback(1000000U/80U,
+                                    FUNCTOR_BIND_MEMBER(&AP_Compass_RM3100::timer, void));
+
+    return true;
+
+//fail:
+//    dev->get_semaphore()->give();
+//    return false;
+}
+
+void AP_Compass_RM3100::timer()
+{
+    struct PACKED {
+        uint8_t magx_2;
+        uint8_t magx_1;
+        uint8_t magx_0;
+        uint8_t magy_2;
+        uint8_t magy_1;
+        uint8_t magy_0;
+        uint8_t magz_2;
+        uint8_t magz_1;
+        uint8_t magz_0;
+    } data;
+    Vector3f field;
+
+    uint32_t magx = 0;
+    uint32_t magy = 0;
+    uint32_t magz = 0;
+
+    // check data ready on 3 axis
+    uint8_t status;
+    if (!dev->read_registers(RM3100_STATUS_REG, (uint8_t *)&status, 1)) {
+        goto check_registers;
+    }
+
+    if (!(status & 0x80)) {
+        // data not available yet
+        goto check_registers;
+    }
+
+    if (!dev->read_registers(RM3100_MX2_REG, (uint8_t *)&data, sizeof(data))) {
+        goto check_registers;
+    }
+
+
+
+    magx = ((uint32_t)data.magx_2 << 16) | ((uint32_t)data.magx_1 << 8) | (uint32_t)data.magx_0;
+    magy = ((uint32_t)data.magy_2 << 16) | ((uint32_t)data.magy_1 << 8) | (uint32_t)data.magy_0;
+    magz = ((uint32_t)data.magz_2 << 16) | ((uint32_t)data.magz_1 << 8) | (uint32_t)data.magz_0;
+
+    if (magx & 0x800000) {
+    	magx |= 0xFF000000;
+    }
+    if (magy & 0x800000) {
+        magy |= 0xFF000000;
+    }
+    if (magz & 0x800000) {
+        magz |= 0xFF000000;
+	}
+
+    field((int32_t)magx * _scaler, (int32_t)magy * _scaler, (int32_t)magz * _scaler);
+
+    // rotate raw_field from sensor frame to body frame
+    rotate_field(field, compass_instance);
+
+    // publish raw_field (uncorrected point sample) for calibration use
+    publish_raw_field(field, compass_instance);
+
+    // correct raw_field for known errors
+    correct_field(field, compass_instance);
+
+    if (_sem->take(HAL_SEMAPHORE_BLOCK_FOREVER)) {
+        accum += field;
+        accum_count++;
+        _sem->give();
+    }
+
+check_registers:
+    dev->check_next_register();
+}
+
+void AP_Compass_RM3100::read()
+{
+    if (!_sem->take_nonblocking()) {
+        return;
+    }
+    if (accum_count == 0) {
+        _sem->give();
+        return;
+    }
+
+#if 0
+    // debugging code for sample rate
+    static uint32_t lastt;
+    static uint32_t total;
+    total += accum_count;
+    uint32_t now = AP_HAL::micros();
+    float dt = (now - lastt) * 1.0e-6;
+    if (dt > 1) {
+    	printf("%u %f samples RM3100 \n", total, dt);
+        lastt = now;
+        total = 0;
+    }
+#endif
+
+    accum /= accum_count;
+
+    publish_filtered_field(accum, compass_instance);
+
+    accum.zero();
+    accum_count = 0;
+
+    _sem->give();
+}

libraries/AP_Compass/AP_Compass_RM3100.h

@@ -0,0 +1,60 @@
+/*
+ * 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/>.
+ */
+#pragma once
+
+#include <AP_Common/AP_Common.h>
+#include <AP_HAL/AP_HAL.h>
+#include <AP_HAL/Device.h>
+#include <AP_Math/AP_Math.h>
+
+#include "AP_Compass.h"
+#include "AP_Compass_Backend.h"
+
+#ifndef HAL_COMPASS_RM3100_I2C_ADDR
+# define HAL_COMPASS_RM3100_I2C_ADDR 0x20
+#endif
+
+class AP_Compass_RM3100 : public AP_Compass_Backend
+{
+public:
+    static AP_Compass_Backend *probe(Compass &compass,
+                                     AP_HAL::OwnPtr<AP_HAL::Device> dev,
+                                     bool force_external = false,
+                                     enum Rotation rotation = ROTATION_NONE);
+
+    void read() override;
+
+    static constexpr const char *name = "RM3100";
+
+private:
+    AP_Compass_RM3100(Compass &compass, AP_HAL::OwnPtr<AP_HAL::Device> dev,
+                       bool force_external,
+                       enum Rotation rotation);
+
+    AP_HAL::OwnPtr<AP_HAL::Device> dev;
+    
+    /**
+     * Device periodic callback to read data from the sensor.
+     */
+    bool init();
+    void timer();
+
+    uint8_t compass_instance;
+    Vector3f accum;
+    uint16_t accum_count;
+    bool force_external;
+    enum Rotation rotation;
+    float _scaler = 1.0;
+};