C030 Battery Charger Voltage Fix

Author: bqam-ublox

targets/TARGET_STM/TARGET_STM32F4/TARGET_STM32F437xG/TARGET_UBLOX_C030/battery_charger_i2c.cpp

@@ -0,0 +1,33 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2006-2017 ARM Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "battery_charger_i2c.h"
+
+BatteryChargerI2c::BatteryChargerI2c(PinName sda, PinName scl):_i2c(), _hz(100000) {
+    i2c_init(&_i2c, sda, scl);
+}
+
+bool BatteryChargerI2c::read_from_i2c(int i2c_address, char* data_read, int length)
+{
+    int bytes_read = i2c_read(&_i2c, i2c_address, data_read, length, 1);
+    return (length == bytes_read);
+}
+
+bool BatteryChargerI2c::write_to_i2c(int i2c_address, const char* data_write, int length)
+{
+    int bytes_written = i2c_write(&_i2c, i2c_address, data_write, length, 1);
+    return (length == bytes_written);
+}

targets/TARGET_STM/TARGET_STM32F4/TARGET_STM32F437xG/TARGET_UBLOX_C030/battery_charger_i2c.h

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+#ifndef BATTERY_CHARGER_I2C
+#define BATTERY_CHARGER_I2C
+
+#include "hal/i2c_api.h"
+
+#ifdef __cplusplus
+extern"C"{
+#endif
+
+class BatteryChargerI2c{
+
+public:
+    BatteryChargerI2c(PinName sda, PinName scl);
+    bool read_from_i2c(int i2c_address, char *data_read, int length);
+    bool write_to_i2c(int i2c_address, const char *data_write, int length);
+    virtual ~BatteryChargerI2c() {}
+
+private:
+    i2c_t _i2c;
+    int   _hz;
+};
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif //BATTERY_CHARGER_I2C

targets/TARGET_STM/TARGET_STM32F4/TARGET_STM32F437xG/TARGET_UBLOX_C030/min_battery_voltage.cpp

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+/* mbed Microcontroller Library
+ * Copyright (c) 2006-2017 ARM Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "min_battery_voltage.h"
+#include "battery_charger_i2c.h"
+
+/** Defining HAL_MspInit strong function
+ * in user defined file as described in documentation
+ */
+
+void HAL_MspInit(void)
+{
+	set_minimum_battery_voltage();
+}
+
+void set_minimum_battery_voltage()
+{
+    char data_write[2] = {0};
+    char data_read;
+    BatteryChargerI2c i2c_object(I2C_SDA_B, I2C_SCL_B);
+
+    if (i2c_object.write_to_i2c(BQ24295_I2C_ADDRESS,&data_write[0] , 1)){
+        i2c_object.read_from_i2c(BQ24295_I2C_ADDRESS, &data_read, 1);
+        data_read = data_read & MIN_BATTERY_VOLTAGE_MASK;
+        data_write[0] = 0x0;
+        data_write[1] = data_read;
+        if (i2c_object.write_to_i2c(BQ24295_I2C_ADDRESS,&data_write[0] , 2)){
+            //Battery Voltage is set to 3880mV
+            }
+        }
+    else{
+        // Minimum battery voltage could not be set.  This is not a critical error, no need to stop execution
+        // It simply means that longer cabling or USB ports with lower output voltages may cause problems.
+    }
+}

targets/TARGET_STM/TARGET_STM32F4/TARGET_STM32F437xG/TARGET_UBLOX_C030/min_battery_voltage.h

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+#ifndef MIN_BATTERY_VOLTAGE_H
+#define MIN_BATTERY_VOLTAGE_H
+
+#ifdef __cplusplus
+extern"C"{
+#endif
+
+#define BQ24295_I2C_ADDRESS (0x6B << 1)
+#define MIN_BATTERY_VOLTAGE_MASK (0x87)
+
+/** Initializes an instance of class BatteryChargerI2c which is using the STM HAL I2C APIs
+ *  This allows longer USB cables or USB ports with lower output voltages to power the board correctly.
+ */
+
+void set_minimum_battery_voltage(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif	// MIN_BATTERY_VOLTAGE_H