Revision 0:5d6ed64426fb, committed 2019-01-11

Comitter:

TakumiToda

Date:

Fri Jan 11 08:00:39 2019 +0000

Commit message:

PCA9547

Changed in this revision

diff -r 000000000000 -r 5d6ed64426fb PCA9547.cpp
--- /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 );
+}

diff -r 000000000000 -r 5d6ed64426fb PCA9547.h
--- /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