Setting up and Running SPI Sample (MPC3008)

MCP3008 Setup

Connections

MCP3008 Pin	Rasp Pi Signal
V_DD	+3.3V
V_REF	+3.3V
AGND	GND
CLK	SCLK
D_OUT	MISO
D_IN	MOSI
CS /SHDN	CE0
DGND	GND

CH<number> pins get connected to the Analog_OUT of the analog circuits

Analog Circuits

Force-sensitive Resistor

Photocell

Potentiometer (Variable Resistor)

Running SPI Sample

First build the dio-spi.jar file:

cd samples/spi

ant

Then copy ../../build/jar/dio-spi.jar to the board.

(On the Pi)
For this example you should have SPIDevice entry in your dio.properties file like this example for the raspberry pi:

12 = deviceType: spibus.SPIDevice, name:SPI_Slave, deviceNumber:0, address:0, csActive:1, wordLength:8, clockFrequency:500000, clockMode:1, bitOrdering:1

Note that these are the current values in the repo which reflect a recent update. Older dio.peprties versions will not work.

sudo $JAVA_HOME/bin/java -Djava.library.path=. -Djava.security.policy=./java.policy -classpath .:./dio.jar:dio-samples.jar:dio-spi.jar -Djdk.dio.registry=./dio.properties -Ddeviceaccess.uart.prefix=/dev/ttyAMA dio.spi.MCP3008Sample

12 4

Note that "12" is the device manager ID number of the SPIDevice in the example property line shown above. "4" selects the channel on the MPC3008. You should use the channel number connected to the analog circuit you're trying to read.