Diff: cpp/I2C.cpp

Revision:

0:fd0d7bdfcdc2

Child:

2:143cac498751

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/cpp/I2C.cpp	Tue Nov 20 17:24:08 2012 +0000
@@ -0,0 +1,98 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2006-2012 ARM Limited
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+#include "I2C.h"
+
+#if DEVICE_I2C
+
+namespace mbed {
+
+I2C *I2C::_owner = NULL;
+
+I2C::I2C(PinName sda, PinName scl) {
+    // The init function also set the frequency to 100000
+    i2c_init(&_i2c, sda, scl);
+    _hz = 100000;
+    
+    // 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 retval = i2c_write(&_i2c, address, data, length, stop);
+    
+    return retval;
+}
+
+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 retval = i2c_read(&_i2c, address, data, length, stop);
+    
+    return retval;
+}
+
+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