===== Digital Analog Converter - MCP4802/22 =====

The MCP4802 is a dual 8-Bit Digital Analog Converter with SPI interface. The MCP4822 is the 12-Bit version.\\

[[http://ww1.microchip.com/downloads/en/devicedoc/20002249b.pdf|MCP4802/22 datasheet]]

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=== WiringPi and the MCP 4802 ===
To connect the MCP 4802  to the Raspberry Pi connect the SPI pins of the MCP4802 like that:\\

{{:raspberry:mcp4802_pinout.jpg?200|}}\\

   MCP4802       Raspberry Pi
   
    Vdd           5V
    CS            CE1
    SCLK          SCLK
    SDI           MOSI
    Vss           GND
    LDAC          GND

{{:puredata:gpio-pinout-diagram-2.png?400|}}\\

Before using the Wiring object enable the SPI interface in:
   $ sudo raspi-config

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==== with Commandline ====

[[https://swharden.com/blog/2016-09-28-generating-analog-voltages-with-the-raspberry-pi/]]\\

to output some voltage:
  $ echo -ne "\x1F\xFF" > /dev/spidev0.1

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==== with BCM2835 Library ====
[[https://www.airspayce.com/mikem/bcm2835/]]\\
[[https://www.youtube.com/watch?v=0QcteUtzB4o]]\\
[[https://raspberry-projects.com/pi/programming-in-c/spi/using-the-spi-interface]]\\


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==== with WiringPi ====

   #include <wiringPiSPI.h>

[[http://wiringpi.com/reference/spi-library/]]\\
[[https://projects.drogon.net/raspberry-pi/wiringpi/spi-library/]]\\
[[https://projects.drogon.net/raspberry-pi/gertboard/analog-inout/]]\\
[[https://projects.drogon.net/understanding-spi-on-the-raspberry-pi/]]\\

[[https://www.petervis.com/Raspberry_PI/Gertboard_Raspberry_Pi_Expansion/Gertboard_Digital_to_Analog_Converter.html]]\\
[[https://learn.sparkfun.com/tutorials/raspberry-pi-spi-and-i2c-tutorial/all]]\\


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==== Links ====

[[https://skpang.co.uk/blog/archives/689]]\\
[[http://www.netzmafia.de/skripten/hardware/RasPi/RasPi_SPI.html]]\\
[[https://github.com/eiWare/LibPiSPI]]\\
[[https://elinux.org/RPi_GPIO_Code_Samples#WiringPi]]\\

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