mcp4822 question Volt output A and B using SPI

Forum 2005-2010 (read only) Hardware Interfacing
#1

The MCP4822 has 2 Volt outputs, i understand from the datasheet. I managed to use one, but i would like to use them both. I like this Arduino and chips to generate CV. Here is the code i use to generate one Volt out

define DATAOUT 11//MOSI - serial data input

define DATAIN 12//MISO - not used, but part of builtin SPI

define SPICLOCK 13//sck - serial clock input

define SLAVESELECT0 10//ss for 1st DAC - chip select input for 1st DAC

//#define SLAVESELECT1 9//ss for 2nd DAC - chip select input for 2nd DAC

include "Spi.h"

const int kGatePin = 2;

int potPin = 2; // select the input pin for the potentiometer int val = 0; // variable to store the value coming from the sensor

void sendNote(int key) { int pitch = 0xa00L * key / 12;

digitalWrite(SS_PIN, LOW); Spi.transfer(0x10 + (pitch >> 8)); Spi.transfer(pitch & 0xff); digitalWrite(SS_PIN, HIGH);

digitalWrite(kGatePin, HIGH); delay(val); digitalWrite(kGatePin, LOW); delay(10); }

void setup() { pinMode(kGatePin, OUTPUT); }

void loop() { val = analogRead(potPin); sendNote(0); sendNote(12); sendNote(11); sendNote(12); sendNote(16); sendNote(12); sendNote(11); sendNote(12);

}

#2

The Question is: How do i name the second VOLT output in the arduino script And what other things do i write in the script so out of the mcp4822 comes on pin 6 AND 8 a voltage range of 0 - 5 volts Now with the mentioned code only out of the pin 8 comes 0 - 5 volts pin 6 does nothing Thanks for the interest, i like Arduino and it's forum Dian de Rocker

#3

Thanks in advance, this might work. Let you know soon. de Rocker

#4

Hello again, Still figuring out how this might work, i changed the 10 = 1010 into other numbers 2 and 3 and 11 but no succes with the other volt output. Only the range off the pitch changes.

What does this mean exactly??? Spi.transfer(0x10 + (pitch >> 8)); Spi.transfer(pitch & 0xff); is the (pitch >> 8) summed with the 0x10 And what does (pitch & 0xff) mean???

Dian

#5