Spi Class Reference

Detailed Description

This file defines the SPI interface for libmraa

        Spi spi = new Spi(0);

        System.out.println("Hello, SPI initialised");
        byte data[] = {0x00, 100};
        for (int cnt = 100; cnt > 0; --cnt) {
            for (int i = 90; i < 130; i++) {
                data[1] = (byte) i;
                byte[] recv = spi.write(data);
                System.out.println(String.format("Writing - %d", i));
                System.out.println(String.format("Received - %d - %d", recv[0], recv[1]));
                Thread.sleep(100);
            }
            for (int i = 130; i > 90; i--) {
                data[1] = (byte) i;
                byte[] recv = spi.write(data);
                System.out.println(String.format("Writing - %d", i));
                System.out.println(String.format("Received - %d - %d", recv[0], recv[1]));
                Thread.sleep(100);
            }
        }

Public Member Functions
synchronized void	delete ()
	Spi (int bus)
	Spi (int bus, int cs)
Result	mode (Spi_Mode mode)
Result	frequency (int hz)
int	writeByte (short data)
int	writeWord (int data)
byte[]	write (byte[] txBuf)
Result	lsbmode (boolean lsb)
Result	bitPerWord (long bits)

Constructor & Destructor Documentation

Spi

(

int

bus

)

Initialise SPI object using the board mapping to set muxes

Parameters

bus	to use, as listed in the platform definition, normally 0

Spi	(	int	bus,
		int	cs
	)

Initialise SPI object using 'raw' mode. Mraa will go and grab the spidev device lablled /dev/spidev[bus].[cs]

Parameters

bus	to use
cs	to use

Member Function Documentation

Result bitPerWord

(

long

bits

)

Set bits per mode on transaction, default is 8

Parameters

bits	bits per word

Returns

Result of operation

Result frequency

(

int

hz

)

Set the SPI device operating clock frequency

Parameters

hz	the frequency to set in hz

Returns

Result of operation

Result lsbmode

(

boolean

lsb

)

Change the SPI lsb mode

Parameters

lsb	Use least significant bit transmission - 0 for msbi

Returns

Result of operation

Result mode

(

Spi_Mode

mode

)

Set the SPI device mode. see spidev0-3

Parameters

mode	the mode. See Linux spidev doc

Returns

Result of operation

int writeByte

(

short

data

)

Write single byte to the SPI device

Parameters

data	the byte to send

Returns

data received on the miso line or -1 in case of error

int writeWord

(

int

data

)

Write single byte to the SPI device

Parameters

data	the byte to send

Returns

data received on the miso line or -1 in case of error

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The documentation for this class was generated from the following file:

• Spi.java