Hello world code for PCA9955A class library. The PCA9955A is a 16-channel Fm+ I2C-bus 57mA/20V constant current LED driver. This program shows its basic operation of PWM and current settings.

Dependencies:   PCA995xA mbed

Please refer to the component page for details

PCA9955B and PCA9956B are I²C-bus controlled 16-channel constant current LED driver optimized for dimming and blinking.

High-level API is available

A high-level API that can be used as the "PwmOut" of bed-SDK is available.
This API enables to make instances of each LED output pins and control PWM duty cycle by assignment.
Output current also controllable by API function.
For detail information, refer API document of LedPwmOutCC Class class which is included in PCA995xA class library.

#include "mbed.h"
#include "PCA9956A.h"

PCA9956A    led_cntlr( p28, p27, 0xC4 );  //  SDA, SCL, Slave_address(option)
LedPwmOutCC led( led_cntlr, L0 );

int main()
{
    while( 1 ) {
        for( float p = 0.0f; p < 1.0f; p += 0.1f ) {
            led     = p;
            wait( 0.1 );
        }
    }
}
Revision:
3:a67c21ad4173
Parent:
2:cfa5103184b1
--- a/main.cpp	Wed Mar 04 10:33:14 2015 +0000
+++ b/main.cpp	Thu Mar 19 08:42:39 2015 +0000
@@ -1,75 +1,32 @@
-#include "mbed.h"
-
-#include "PCA9955A.h"
-PCA9955A    led_cntlr( p28, p27, 0x02 );    //  SDA, SCL, Slave_address(option)
-
-int main()
-{
-    led_cntlr.current( ALLPORTS, 1.0 ); //  Set all ports output current 100%
-
-    while(1) {
-        for ( int port = 0; port < led_cntlr.number_of_ports(); port++ ) {
-            for ( int i = 1; i <= 100; i++ ) {
-                led_cntlr.pwm(  port, (float)i / 100.0 );
-                wait( 0.01 );
-            }
-        }
-        led_cntlr.pwm( ALLPORTS, 0.0 ); //  Set all ports output PWM 0%
-    }
-}
-
-
-
-#if 0  //  Sample of using LedPwmOut API
 #include "mbed.h"
 #include "PCA9955A.h"
 
-PCA9955A    led_cntlr( p28, p27, 0x02 );
-LedPwmOutCC   leds[]  = {
-    LedPwmOutCC( led_cntlr, L0  ),
-    LedPwmOutCC( led_cntlr, L4  ),
-    LedPwmOutCC( led_cntlr, L8  ),
-    LedPwmOutCC( led_cntlr, L12 ),
-
-    LedPwmOutCC( led_cntlr, L1  ),
-    LedPwmOutCC( led_cntlr, L5  ),
-    LedPwmOutCC( led_cntlr, L9  ),
-    LedPwmOutCC( led_cntlr, L13 ),
-
-    LedPwmOutCC( led_cntlr, L2  ),
-    LedPwmOutCC( led_cntlr, L6  ),
-    LedPwmOutCC( led_cntlr, L10  ),
-    LedPwmOutCC( led_cntlr, L14 ),
-
-    LedPwmOutCC( led_cntlr, L3  ),
-    LedPwmOutCC( led_cntlr, L7  ),
-    LedPwmOutCC( led_cntlr, L11  ),
-    LedPwmOutCC( led_cntlr, L15 ),
-
-};
+PCA9955A    led_cntlr( p28, p27, 0x02 );    //  SDA, SCL, Slave_address(option)
+LedPwmOutCC led0( led_cntlr, L0  );         //  Instance for LED0 pin
+LedPwmOutCC led1( led_cntlr, L1  );         //  Instance for LED1 pin
+LedPwmOutCC led2( led_cntlr, L2  );         //  Instance for LED2 pin
 
 int main()
 {
-    for ( int ch = 0; ch < 16; ch++ )
-        leds[ ch ]  = 1.0;
-    for ( int ch = 0; ch < 16; ch++ )
-        leds[ ch ].current( 0.0 );
+    led0.current( 0.5 );    //  LED0 pin current output setting to 50%
+    led1.current( 0.5 );    //  LED1 pin current output setting to 50%
+    led2.current( 0.5 );    //  LED2 pin current output setting to 50%
 
     while(1) {
-        for ( int ch = 0; ch < 16; ch++ ) {
-            for ( float p = 0.0; p < 1.0; p += 0.01 ) {
-//                leds[ ch ]  = p;
-                leds[ ch ].current( p );
-                wait( 0.01 );
-            }
+        
+        for ( float p = 1.0; p >= 0.0; p -= 0.01 ) {
+            led0    = p;    //  Set LED0 output PWM dutycycle as 'p'
+            wait( 0.01 );
         }
-        for ( float c = 1.0; c > 0.0; c -= 0.01 ) {
-            for ( int ch = 0; ch < 16; ch++ ) {
-                leds[ ch ].current( c );
-
-            }
+        
+        for ( float p = 1.0; p >= 0.0; p -= 0.01 ) {
+            led1    = p;    //  Set LED1 output PWM dutycycle as 'p'
+            wait( 0.01 );
+        }
+        
+        for ( float p = 1.0; p >= 0.0; p -= 0.01 ) {
+            led2    = p;    //  Set LED2 output PWM dutycycle as 'p'
             wait( 0.01 );
         }
     }
 }
-#endif
\ No newline at end of file