Alan Rager / Mbed 2 deprecated apa102

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apa102 Class Reference
Public Member Functions

apa102 Class Reference

APA102 class, controlling LED strips or arrays like this http://www.sparkfun.com/products/10312. More...

#include <apa102.h>

Public Member Functions

 apa102 (PinName CKI, PinName SDI, int STRIP_LENGTH=32, int reset_delay=800)
 Create a new apa102 object.
void post (int *strip_colors)
 write RGB color data to strip or array
void clear (void)
 clears the array or strip (all off)
int level (int level=0)
 set level of the entire array 0-100%
int delay (uint32_t reset_delay=100)
 get/set reset/write delay

Detailed Description

APA102 class, controlling LED strips or arrays like this http://www.sparkfun.com/products/10312.

the APA102 IC's are 5V but works well connected directly to mbed IO pins.

You need a 5V power supply capable of about 2A to light up a 32 led strip, do NOT power from mbed(usb).

the required reset delay is a blocking wait(), it can be lowered (or set to 0) if you want to use the time for executing code instead, data sheet says 500us but i found it need at least 800us.

Example: 

#include "mbed.h"
#include "apa102.h"

#define STRIP_LENGTH 32

apa102 mystrip(p9, p10, STRIP_LENGTH);

int dir=1, level=10;
int rainbow[] = {0xff00ff,0xff00cc,0xff0099,0xff0066,0xff0033,0xff0000,0xff3300,0xff6600,
                 0xff9900,0xffcc00,0xffff00,0xccff00,0x99ff00,0x66ff00,0x33ff00,0x00ff00,
                 0x00ff33,0x00ff66,0x00ff99,0x00ffcc,0x00ffff,0x00ccff,0x0099ff,0x0066ff,
                 0x0033ff,0x0000ff,0x3300ff,0x6600ff,0x9900ff,0xcc00ff,0x9900ff,0x6600ff
                };
              
void move(void){
    int temp = rainbow[31];
    for (int x = (STRIP_LENGTH - 1) ; x > 0 ; x--) rainbow[x] = rainbow[x - 1];
    rainbow[0] = temp;
}    

void pulse(void){
    if(dir)
      {
      mystrip.level(level+=2);
      if(level >= 100)dir = 0;
      }
    else if(!dir)
    {
    mystrip.level(level--);
    if(level <= 5)dir = 1;    
    }
}
       
int main() {
    mystrip.level(level);
    while(1)
      {
      move();
      pulse();
      mystrip.post(rainbow);
      wait_ms(100);
      }
}

Definition at line 87 of file apa102.h.

Constructor & Destructor Documentation

apa102 ( PinName  CKI,
PinName  SDI,
int  STRIP_LENGTH = 32,
int  reset_delay = 800 
)

Create a new apa102 object.

Parameters:
CKIclock pin
SDIdata pin
STRIP_LENGTHnumber of apa102 IC's i strip or array defaults to 32
reset_delaydelay in us to allow latching data defaults to 800
Returns:
nothing

Definition at line 7 of file apa102.cpp.

Member Function Documentation

void clear ( void   )

clears the array or strip (all off)

Definition at line 29 of file apa102.cpp.

int delay ( uint32_t  reset_delay = 100 )

get/set reset/write delay

mainly for experimenting with reset values without recompiling, leave at default to begin with & then lower to get faster execution.

Parameters:
delaydelay in us
Returns:
delay in us

Definition at line 46 of file apa102.cpp.

int level ( int  level = 0 )

set level of the entire array 0-100%

at low levels the colors may change because R,G or B reaches 0.

Parameters:
levellevel in percent
Returns:
current level

Definition at line 35 of file apa102.cpp.

void post ( int *  strip_colors )

write RGB color data to strip or array

color data for each LED is 3 bytes int the order of rrggbb. array must have STRIP_LENGTH number of elements

Parameters:
strip_colorsarray of color data

Definition at line 15 of file apa102.cpp.

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