Hi,
I have been wanting to get an Arduino up and running for a long time, and I finally got the job done today, thanks to GLT and his hifiduino site. It is still in prototype mode, and needs some tweaking, but it is working.

My setup is a MUX i2s and an Amanero USB-i2s into an OTTO and the output of the OTTO into a Buffalo II.

I would like to be able to use the Arduino to switch the OTTO and the MUX, so that when I switch inputs it automatically switches the OTTO and the MUX to the appropriate input. Does anyone have any working code for either? It would be great to be able to see how someone else did it before I go and try to hack my own (I know some Python and Java, but no C). I tried searching, but didn't find anything here, or on github, but I might not have searched correctly.

Thank you for taking the time to read my post.

I am just using a relay to switch the OTTO as per the setup below, Russ say you can switch without the relay but I and others had issues with that so I just stayed with the relay, its simple & also helps isolate the BIII from the Arduino.

All you need to do is send the relay High & Low to switch. If you need any help with the code let me know.

Edited by user Sunday, May 12, 2013 11:29:33 AM(UTC)  | Reason: Not specified

Hi Russ,
Where do I put the resistor when using OTTO S - level converter - Arduino digital pin for control?

I did a bit of practice work with the Arduino code and figured out how to change it to work with the OTTO and MUX with the hifiduino code. Now I just have to get the white apple remote I have to work with all of it's buttons.

I was able to change the code to get the MUX and the OTTO hooked up and working so that they switch with the input changes with the hifiduino code. I am using a 5 volt to 3.3 volt level converter (same one I am using for the i2c connection for the buffalo II) to connect the OTTO, and direct 5 volts for the MUX.

My setup is the 4/1 MUX to i2s into OTTO, an Amanero USB i2s into OTTO, and OTTO into Buffalo II.

Here is how I modified the code, in case someone else wants to do this as well. Hopefully this will help. Line numbers are tricky in the Arduino IDE. To find the line number, look at the bottom. The line number of the cursor is displayed.

I decided to use analog pins A0, A1, and A2 on the Arduino Uno to control the OTTO and the MUX. Two pins for the MUX, and one for the OTTO. They can also be used as digital pins 14, 15, and 16 respectively. I connected pins 14 and 15 to MUX control 0 and 1, and pin 16 to the 5 volt side of the level converter, and the 3.3 volt side to OTTO S. I also connected the GND connection on the MUX control to the GND on the Arduino.

At line 1220, I added code to make the analog pins digital output pins on the arduino.

pinMode(14, OUTPUT)
pinMode(15, OUTPUT)
pinMode(16, OUTPUT)


Then under each input, I set the pins to LOW or HIGH so that the correct input would be selected. On HIGH, the pin outputs 5 volts. On LOW, the pin outputs close to 0 volts. Testing the circuit with LCD's confirmed that the once a pin is set to HIGH or LOW, it will stay there unless it is told to change on the following input. I made sure to turn off pins that I did not need on for each input. Here is how I modified the code to turn the pins on and off to switch the MUX and OTTO.

The digitalWrite() lines are the ones that I added. The first two inputs set the OTTO to output the Amanero. The third sets the OTTO to the side with the MUX, and selects input 1 on the MUX. Then input 2, then 3, then back to the Amanero again.

case 0:
lcd.print(no0);
digitalWrite(16, LOW);
break;
case 1:
lcd.print(no1);
digitalWrite(16, LOW);
break;
case 2:
lcd.print(no2);
digitalWrite(16, HIGH);
digitalWrite(14, LOW);
digitalWrite(15, LOW);
break;
case 3:
lcd.print(no3);
digitalWrite(16, HIGH);
digitalWrite(14, HIGH);
digitalWrite(15, LOW);
break;
case 4:
lcd.print(no4);
digitalWrite(16, HIGH);
digitalWrite(14, LOW);
digitalWrite(15, HIGH);
break;
case 5:
lcd.print(no5);
digitalWrite(16, LOW);
digitalWrite(15, LOW);
digitalWrite(14, LOW);
break;

Edited by user Thursday, May 16, 2013 2:48:45 AM(UTC)  | Reason: added that I connected GND from MUX control to arduino

Thanks Russ! I will add the resistor. I already had one installed differently when I had an analog switch for the OTTO.

Any thoughts?

Hi DQ828,

I suggest using either pull-up or pull-down resistors, not both as it will result in a /2 voltage divider and a "floating" reference.
Using some 1K resistors may provide sharper transitions.

Here a code snippet to use with Otto Board https://codebender.cc/sketch:95185