rpi_spi

Description:

rpi spi

rpi_spi.dart #

rpi_spi is a Dart package for using SPI on the Raspberry Pi.
Overview #


The Spi library provides the API for accessing devices
using the SPI protocol


The RpiSpi library provides implementation of
the SPI protocol on the Raspberry Pi derived from the WiringPi library.


Setup #
Be sure to enable SPI on the Raspberry Pi using
sudo raspi-config
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RpiSpi uses a native library written in C.
For security reasons, authors cannot publish binary content
to pub.dartlang.org, so there are some extra
steps necessary to compile the native library on the RPi before this package
can be used. These two steps must be performed when you install and each time
you upgrade the rpi_spi package.

Activate the rpi_spi package using the
pub global command.

pub global activate rpi_spi
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From your application directory (the application that references
the rpi_spi package) run the following command to build the native library

pub global run rpi_spi:build_native
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pub global activate
makes the Dart scripts in the rpi_spi/bin directory runnable
from the command line.
pub global run
rpi_spi:build_native runs the rpi_spi/bin/build_native.dart
program which in turn calls the build_native script
to compile the native librpi_spi_ext.so library for the rpi_spi package.
Example #


example.dart demonstrates instantiating and accessing a SPI device.


mcp3008.dart demonstractes how the SPI API is used
to interact with a MCP3008
analog to digital converter


Connect the following pins on the Raspberry Pi
to the following pins on the Adafruit MCP3008.
Pi pins 13 and 15 are connected to MCP3008 input #0 both for the example and as a predictable test input.
The other connected Pi pins are for controlling the MCP3008 and reading it's output values via the SPI API.



Rpi Pin
MCP3008




PIN #13 to 4.7K resistor to --->
PIN #1 (CH0)


PIN #15 to 10K resistor to --->
PIN #1 (CH0)


PIN #17 (3.3V)
PIN #16 (VDD) & PIN #15 (VREF)


PIN #19 (SPI0 MOSI)
PIN #11 (DIN)


PIN #21 (SPI0 MISO)
PIN #12 (DOUT)


PIN #23 (SIP0 SCLK)
PIN #13 (CLK)


PIN #24 (SPI0 CS0)
PIN #10 (CS/SHDN)


PIN #25 (GND)
PIN #9 (DGND) & PIN #14 (AGND)