InetrfaceProducts NXP / PCA9622_LED8x8

Library for "I2C 8x8 LED matrix board" from Switch Science https://www.switch-science.com/catalog/2071/

Dependents:   PCA9622_LED8x8_Demo PCA9622_LED8x8_Hello PCA9622_LED8x8_x6_Demo shake-shake-machine

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PCA9622_LED8x8 Class Reference
Public Member Functions

PCA9622_LED8x8 Class Reference

PCA9622_LED8x8 class. More...

#include <PCA9622_LED8x8.h>

Public Member Functions

 PCA9622_LED8x8 (PinName sda, PinName scl, char slave_adr=0xA0, float fr=DEFAULT_FRAMERATE)
 Create a PCA9622_LED8x8 instance for the LED matrix board which is connected to specified I2C pins with specified address.
 PCA9622_LED8x8 (I2C &i2c_obj, char slave_adr=0xA0, float fr=DEFAULT_FRAMERATE)
 Create a PCA9622_LED8x8 instance for the LED matrix board which is connected to specified I2C pins with specified address.
 ~PCA9622_LED8x8 ()
 Destructor of PCA9622_LED8x8.
void frame_rate (float rate)
 Frame rate change.
void start (void)
 Start operation.
void stop (void)
 Stop operation.
void set_data (float p[8][8])
 Set the image to library internal buffer.

Detailed Description

PCA9622_LED8x8 class.

PCA9622_LED8x8: A library to control LED matrix using the PCA9622

PCA9622 is an I2C LED controller. This library operates LED 8x8 matrix through the PCA9622.

Example: 

  #include "mbed.h"
  #include "PCA9622_LED8x8.h"

  PCA9622_LED8x8  matrix( p28, p27 );     //  for 40pin type mbed
  //PCA9622_LED8x8  matrix( D14, D15 );   //  for Arduino type mbed
  //PCA9622_LED8x8  matrix( dp5, dp27 );  //  for mbed LPC1114

  float func( float x, float y, float t );    //  function to make 8x8 image

  int main()
  {
      float   image[ 8 ][ 8 ];  //
      int     count   = 0;

      matrix.start();

      while(1) {

          //  making 8x8 image to "image" array
          for ( int i = 0; i < 8; i++ )
              for ( int j = 0; j < 8; j++ )
                  image[ i ][ j ]   = func( i, j, count * 0.2 );

          matrix.set_data( image );

          count++;
          wait( 0.05 );
      }
  }

  float func( float x, float y, float t )
  {
  //#define     DISPLAY_OFFSET  3.5
  #define     DISPLAY_OFFSET  0
  #define     SIZE            0.3

      float   s;

      x   = (x - DISPLAY_OFFSET) * SIZE;
      y   = (y - DISPLAY_OFFSET) * SIZE;

      s   = cos( powf( x * x + y * y, 0.5 ) - t );
      return ( powf( s, 4.0 ) );
  }

Definition at line 79 of file PCA9622_LED8x8.h.

Constructor & Destructor Documentation

PCA9622_LED8x8 ( PinName  sda,
PinName  scl,
char  slave_adr = 0xA0,
float  fr = DEFAULT_FRAMERATE 
)

Create a PCA9622_LED8x8 instance for the LED matrix board which is connected to specified I2C pins with specified address.

PCA9622 LED 8x8 library.

Parameters:
sdaI2C-bus SDA pin
sclI2C-bus SCL pin
slave_adr(option) I2C-bus address (default: 0xA0)
fr(option) frame rate (in "Hz". default: 100)
Author:
Tedd OKANO
Version:
1.1.1
Date:
26-Feb-2015

Library for "I2C 8x8 LED matrix board" from Switch Science https://www.switch-science.com/catalog/2071/

The I2C LED controller PCA9622 is used on this module that ebables to control the LEDs with PWM brightness control.

For more information about the PCA9622: http://www.nxp.com/documents/data_sheet/PCA9622.pdf

Definition at line 21 of file PCA9622_LED8x8.cpp.

PCA9622_LED8x8 ( I2C &  i2c_obj,
char  slave_adr = 0xA0,
float  fr = DEFAULT_FRAMERATE 
)

Create a PCA9622_LED8x8 instance for the LED matrix board which is connected to specified I2C pins with specified address.

Parameters:
i2c_objI2C object (instance)
slave_adr(option) I2C-bus address (default: 0xA0)
fr(option) frame rate (in "Hz". default: 100)

Definition at line 36 of file PCA9622_LED8x8.cpp.

~PCA9622_LED8x8 (  )

Destructor of PCA9622_LED8x8.

Definition at line 51 of file PCA9622_LED8x8.cpp.

Member Function Documentation

void frame_rate ( float  rate )

Frame rate change.

Changes frame rate (scan rate of the matrix)

Parameters:
rateFrame rate in "Hz"

Definition at line 71 of file PCA9622_LED8x8.cpp.

void set_data ( float  p[8][8] )

Set the image to library internal buffer.

8x8 pixel image will be copied into the library internal buffer. User don't need to care the timing of this function call because the library is using "ping-pong" buffering. This function writes data into in-active side of the buffer. The image will not be appear immediatly but from next scan start.

Each elements of the array should be brightness information in range of 0.0 to 1.0.

The 2 dimensional 8x8 array will be handled as..

p[0][0] : top-left p[0][7] : top-right p[7][0] : bottm-left p[7][7] : bottom-right

Parameters:
pimage stored 2-dimensional float array

Definition at line 129 of file PCA9622_LED8x8.cpp.

void start ( void   )

Start operation.

The LED matrix operation need to be started with this function. Scan line drawing by Ticker interrupt will be started.

Definition at line 84 of file PCA9622_LED8x8.cpp.

void stop ( void   )

Stop operation.

This stops the operation. Ticker interrupt will be stopped

Definition at line 90 of file PCA9622_LED8x8.cpp.

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