Diff: common/I2C.cpp

Revision:

0:7e2bd16f80af

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/common/I2C.cpp	Sat Jan 17 18:03:58 2015 +0000
@@ -0,0 +1,91 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2006-2013 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 "I2C.h"
+
+#if DEVICE_I2C
+
+namespace mbed {
+
+I2C *I2C::_owner = NULL;
+
+I2C::I2C(PinName sda, PinName scl) : _i2c(), _hz(100000) {
+    // The init function also set the frequency to 100000
+    i2c_init(&_i2c, sda, scl);
+
+    // Used to avoid unnecessary frequency updates
+    _owner = this;
+}
+
+void I2C::frequency(int hz) {
+    _hz = hz;
+
+    // We want to update the frequency even if we are already the bus owners
+    i2c_frequency(&_i2c, _hz);
+
+    // Updating the frequency of the bus we become the owners of it
+    _owner = this;
+}
+
+void I2C::aquire() {
+    if (_owner != this) {
+        i2c_frequency(&_i2c, _hz);
+        _owner = this;
+    }
+}
+
+// write - Master Transmitter Mode
+int I2C::write(int address, const char* data, int length, bool repeated) {
+    aquire();
+
+    int stop = (repeated) ? 0 : 1;
+    int written = i2c_write(&_i2c, address, data, length, stop);
+
+    return length != written;
+}
+
+int I2C::write(int data) {
+    return i2c_byte_write(&_i2c, data);
+}
+
+// read - Master Reciever Mode
+int I2C::read(int address, char* data, int length, bool repeated) {
+    aquire();
+
+    int stop = (repeated) ? 0 : 1;
+    int read = i2c_read(&_i2c, address, data, length, stop);
+
+    return length != read;
+}
+
+int I2C::read(int ack) {
+    if (ack) {
+        return i2c_byte_read(&_i2c, 0);
+    } else {
+        return i2c_byte_read(&_i2c, 1);
+    }
+}
+
+void I2C::start(void) {
+    i2c_start(&_i2c);
+}
+
+void I2C::stop(void) {
+    i2c_stop(&_i2c);
+}
+
+} // namespace mbed
+
+#endif