Diff: I2CX.cpp

Revision:

0:3d97d631d8dd

Child:

2:9d9fc94594e3

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/I2CX.cpp	Wed Oct 22 10:25:32 2014 +0000
@@ -0,0 +1,103 @@
+/* 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 "I2CX.h"
+
+#if DEVICE_I2C
+
+namespace mbed {
+
+I2CX *I2CX::_owner = NULL;
+
+I2CX::I2CX(I2CName peripheral, PinName sda, PinName scl) : _i2c(), _hz(100000) {
+    
+    // Hacky way to get around pin mapping
+    if(peripheral == I2C_0) {
+        i2c_init(&_i2c, p22, p20);
+    }
+    else if(peripheral == I2C_1) {
+        i2c_init(&_i2c, p13, p15);
+    }
+    else {
+        i2c_init(&_i2c, NC, NC);
+    }
+    
+    _i2c.sda = sda;
+    _i2c.scl = scl;
+    
+    // Used to avoid unnecessary frequency updates
+    _owner = this;
+}
+
+void I2CX::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 I2CX::aquire() {
+    if (_owner != this) {
+        i2c_frequency(&_i2c, _hz);
+        _owner = this;
+    }
+}
+
+// write - Master Transmitter Mode
+int I2CX::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 I2CX::write(int data) {
+    return i2c_byte_write(&_i2c, data);
+}
+
+// read - Master Reciever Mode
+int I2CX::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 I2CX::read(int ack) {
+    if (ack) {
+        return i2c_byte_read(&_i2c, 0);
+    } else {
+        return i2c_byte_read(&_i2c, 1);
+    }
+}
+
+void I2CX::start(void) {
+    i2c_start(&_i2c);
+}
+
+void I2CX::stop(void) {
+    i2c_stop(&_i2c);
+}
+
+} // namespace mbed
+
+#endif