/* Digital Pot Control This example controls an Analog Devices AD5206 digital potentiometer. The AD5206 has 6 potentiometer channels. Each channel's pins are labeled A - connect this to voltage W - this is the pot's wiper, which changes when you set it B - connect this to ground. The AD5206 is SPI-compatible,and to command it, you send two bytes, one with the channel number (0 - 5) and one with the resistance value for the channel (0 - 255). The circuit: * All A pins of AD5206 connected to +5V * All B pins of AD5206 connected to ground * An LED and a 220-ohm resisor in series connected from each W pin to ground * CS - to digital pin 10 (SS pin) * SDI - to digital pin 11 (MOSI pin) * CLK - to digital pin 13 (SCK pin) created 10 Aug 2010 by Tom Igoe Thanks to Heather Dewey-Hagborg for the original tutorial, 2005 */ // inslude the SPI library: #include void setup() { // set pin 10 as the slave select for the digital pot: pinMode (10, OUTPUT); // initialize SPI: SPI.begin(); } void loop() { // go through the six channels of the digital pot: for (int channel = 0; channel < 6; channel++) { // change the resistance on this channel from min to max: for (int level = 0; level < 255; level++) { digitalPotWrite(channel, level); delay(10); } // wait a second at the top: delay(100); // change the resistance on this channel from max to min: for (int level = 0; level < 255; level++) { digitalPotWrite(channel, 255 - level); delay(10); } } } int digitalPotWrite(int address, int value) { // take the SS pin low to select the chip: digitalWrite(10,LOW); // send in the address and value via SPI: SPI.transfer(address); SPI.transfer(value); // take the SS pin high to de-select the chip: digitalWrite(10,HIGH); }