Takumi Toda / PCA9547

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Comitter:
TakumiToda
Date:
Fri Jan 11 08:00:39 2019 +0000
Commit message:
PCA9547

Changed in this revision

PCA9547.cpp Show annotated file Show diff for this revision Revisions of this file
PCA9547.h Show annotated file Show diff for this revision Revisions of this file
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/PCA9547.cpp	Fri Jan 11 08:00:39 2019 +0000
@@ -0,0 +1,52 @@
+/**
+ *  PCA9547 library
+ *
+ *  @author  Tedd OKANO
+ *  @version 0.2
+ *  @date    Feb-2015
+ *
+ *  PCA9547: an I2C bus multiplexer control library
+ *
+ *  PCA9547 is an I2C multiplexer which enables to select 1:8 multiplexed I2C bus.
+ *  The multiplexer is useful for deviding I2C bus to avoiding slave address conflict and separating capacitive loads.
+ *
+ *  For more information about PCA9547:
+ *    http://www.nxp.com/documents/data_sheet/PCA9547.pdf
+ *
+ */
+
+#include "PCA9547.h"
+
+PCA9547::PCA9547( PinName sda, PinName scl, char i2c_address )
+    : i2c_p( new I2C( sda, scl ) ), i2c( *i2c_p ), i2c_addr( i2c_address )
+{
+    //  do nothing.
+    //  leave it in default state.
+}
+
+PCA9547::PCA9547( I2C &i2c_, char i2c_address )
+    : i2c_p( NULL ), i2c( i2c_ ), i2c_addr( i2c_address )
+{
+    //  do nothing.
+    //  leave it in default state.
+}
+
+PCA9547::~PCA9547()
+{
+    if ( NULL != i2c_p )
+        delete  i2c_p;
+}
+
+void PCA9547::select( char channel )
+{
+    char    data    = 0x08 | channel;
+
+    i2c.write( i2c_addr, &data, 1 );
+}
+
+void PCA9547::disable( void )
+{
+    char    data    = 0x00;
+
+    i2c.write( i2c_addr, &data, 1 );
+}
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/PCA9547.h	Fri Jan 11 08:00:39 2019 +0000
@@ -0,0 +1,98 @@
+/**
+ *  PCA9547 library
+ *
+ *  @author  Tedd OKANO
+ *  @version 0.2
+ *  @date    Feb-2015
+ *
+ *  PCA9547: an I2C bus multiplexer control library
+ *
+ *  PCA9547 is an I2C multiplexer which enables to select 1:8 multiplexed I2C bus.
+ *  The multiplexer is useful for deviding I2C bus to avoiding slave address conflict and separating capacitive loads.
+ *
+ *  For more information about PCA9547:
+ *    http://www.nxp.com/documents/data_sheet/PCA9547.pdf
+ *
+ */
+
+#ifndef MBED_PCA9547_H
+#define MBED_PCA9547_H
+
+#include "mbed.h"
+
+/** PCA9547 class
+ *
+ *  PCA9547: an I2C bus multiplexer control library
+ *
+ *  PCA9547 is an I2C multiplexer which enables to select 1:8 multiplexed I2C bus.
+ *  The multiplexer is useful for deviding I2C bus to avoiding slave address conflict and separating capacitive loads.
+ *
+ *  For more informatioj about PCA9547:
+ *    http://www.nxp.com/documents/data_sheet/PCA9547.pdf
+ *
+ *  Example:
+ *  @code
+ *  #include "mbed.h"
+ *  #include "LM75B.h"
+ *  #include "PCA9547.h"
+ *
+ *  PCA9547 mux( p28, p27, 0xE0 );
+ *
+ *  int main()
+ *  {
+ *      mux.select( 0 );
+ *
+ *      LM75B   tmp0( p28, p27 );   //  making instance after a branch of I2C bus (which is connecting the LM75B) enabled
+ *
+ *      while(1) {
+ *          printf( "%.3f\r\n", tmp0.read() );
+ *          wait( 1.0 );
+ *      }
+ *  }
+ *  @endcode
+ */
+
+class PCA9547
+{
+public:
+
+    /** Create a PCA9547 instance connected to specified I2C pins with specified address
+     *
+     * @param sda I2C-bus SDA pin
+     * @param scl I2C-bus SCL pin
+     * @param i2c_address I2C-bus address (default: 0xE0)
+     */
+    PCA9547( PinName sda, PinName scl, char i2c_address = 0xE0 );
+
+    /** Create a PCA9546A instance connected to specified I2C pins with specified address
+     *
+     * @param &i2c_ I2C object (instance)
+     * @param i2c_address I2C-bus address (default: 0xE0)
+     */
+    PCA9547( I2C &i2c_, char i2c_address = 0xE0 );
+
+    /** Destructor of PCA9547
+     */
+    ~PCA9547();
+
+    /** Channel select
+     *
+     *  Enable and select a channel
+     *
+     * @param channel channel number
+     */
+    void select( char channel );
+
+    /** Disabling all channels
+     *
+     *  Disable all channels
+     */
+    void disable( void );
+
+private:
+    I2C     *i2c_p;
+    I2C     &i2c;
+    char    i2c_addr;
+};
+
+#endif  //  MBED_PCA9547_H