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.
Please refer to the component page for details
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 ); } } }
main.cpp
- Committer:
- nxp_ip
- Date:
- 2015-03-19
- Revision:
- 3:a67c21ad4173
- Parent:
- 2:cfa5103184b1
- Child:
- 5:e2ad761c8570
File content as of revision 3:a67c21ad4173:
#include "mbed.h" #include "PCA9955A.h" 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() { 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 ( float p = 1.0; p >= 0.0; p -= 0.01 ) { led0 = p; // Set LED0 output PWM dutycycle as 'p' wait( 0.01 ); } 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 ); } } }