Ollie Milton / DigiPot

A simple library for controlling an MCP4241 digital potentiometer

DigiPot.cpp

Committer:
ollie8
Date:
2014-01-25
Revision:
1:179b46a0165e
Parent:
0:f547d674e543
Child:
2:54e9d9ddc350

File content as of revision 1:179b46a0165e:

#include "DigiPot.h"
#include "math.h"

#define POT_0 0x00
#define POT_1 0x10

DigiPot::DigiPot(PinName miso, PinName mosi, PinName clk, PinName cs) {
    chsel = new DigitalOut(cs);
    spi = new SPI(mosi, miso, clk);
    spi->format(8,0); 
    spi->frequency(1000000);
    level = 0x00;
}

void DigiPot::increment() {
    setLevel(level++);
}

void DigiPot::decrement() {
    setLevel(level--);
}

void DigiPot::setLevel(unsigned char level) {
    *chsel = 0;
    spi->write(POT_0);
    spi->write(level);
    *chsel = 1;
    wait_us(2);
    *chsel = 0;
    spi->write(POT_1);
    spi->write(level);
    *chsel = 1;
}

void DigiPot::mute() {
    setLevel(0x00);
}

void DigiPot::unmute() {
    setLevel(level);
}

unsigned char DigiPot::getLevel() {
    return level;
}