Tag: electronics

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Arduino INPUT_PULLUP mode

notes

When reading the value of a switch with Arduino, its useful to set the INPUT_PULLUP mode so you don’t need to use an external pullup resistor. By the way, the internal pull-up resistor is 20K ohms.

See this tutorial:

http://arduino.cc/en/Tutorial/InputPullupSerial

If its not clear what a pull-up resistor does,  read the links on this forum post.

http://arduino.cc/forum/index.php/topic,22274.0.html

Everybody has their own way to explain it. I would say that when the switch is open, the pull-up resistor weakly pulls the logic value high, so you don’t get random signal readings.

 

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Raspberry Pi sound cards

notes

http://elinux.org/RPi_VerifiedPeripherals#USB_Sound_Cards

A post about installing USB sound cards

http://www.raspberrypi.org/phpBB3/viewtopic.php?t=20866

And another – with better detail

http://www.jackenhack.com/raspberry-pi-usb-audio-quality-problems/

http://raspberrypi.stackexchange.com/questions/3888/how-to-install-usb-sounds-adapter

Griffin imic with PD

http://iamthemightyjungulator.blogspot.com/2012/12/raspberry-pi-usb-sound-into-pure-data.html

 

 

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Midi and bluetooth

notes

Bluetooth to Midi converter:

By Mike Szczys at Hackaday

http://hackaday.com/2011/07/09/turn-any-bluetooth-device-into-a-midi-controller/

Cheap 2-Way Bluetooth Connection Between Arduino and PC

By Techbitar at Instructables

http://www.instructables.com/id/Cheap-2-Way-Bluetooth-Connection-Between-Arduino-a/?ALLSTEPS

Arduino to Android using Bluetooth

By Brian Jepson at Make

http://blog.makezine.com/2012/03/19/bluetooth-4-0-from-arduino-to-iphone-no-jailbreaking-no-mfi/

 

 

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MIDI wireless options

A thought exercise – to come up with various ways of making wireless Midi systems based on projects I’ve already done.

  • any combination of iOS and MacOS devices
  • use touchOSC with above setup
  • Arduino + ethernet shield to wifi router to touchOSC
  • Same as above but using wifi bridge to connect to router*
  • Arduino + wifi shield via UDP*
  • Arduino + wireless SD + xbee to same – one end connected to mac OS device
  • IR emitter/detector pair*
  • Arduino + wireless SD + WiFly rn-xv via UDP*
  • bluetooth* (here’s an app called bluemidi http://www.iosmusician.com/category/bluetooth-midi-on-ios
  • modulated laser pointer and solar panel*
  • convert to audio then use any audio transmission method and convert back to midi*
  • Use RTTY with ham radio*
  • cell phone*

* indicates method not tried yet.