com.iotize.jvm.hal

Class Spi

java.lang.Object

com.iotize.jvm.hal.Spi

public class Spi
extends java.lang.Object

IoTize class to manage the SPI (Serial Peripheral Interface).

Field Summary

Fields

Modifier and Type	Field and Description
static int	HAS_CS
static int	MAX_FRAME_SIZE
static int	MAX_TIMEOUT
static int	NO_CS
static int	SPI_POL0_PHA0
static int	SPI_POL0_PHA1
static int	SPI_POL1_PHA0
static int	SPI_POL1_PHA1

Constructor Summary

Constructors

Constructor and Description
Spi(int spiFrequency, int spiMode, int spiUseCs) Creates a Master Spi interface at the specified frequency.
Spi(int target, int spiFrequency, int spiMode, int spiUseCs) Creates a Master Spi interface at the specified frequency.

Method Summary

Modifier and Type	Method and Description
int	fill(byte[] buffer, int numberOfTimes) Sends the provided buffer repeatedly.
int	readBytes(byte[] buffer, int length, int timeout) Read the requested bytes through the SPI port and store them in the given buffer.
int	sendBitMap(byte[] bitmap, int width, int height, int scaling, short colorOn, short colorOff) Transforms the given bitmap, replacing every bit (MSB to LSB) by the corresponding colorOn / colorOff short value.
int	writeBytes(byte[] buffer, int length, int timeout) Write the given buffer through the SPI port
int	writeReadBytes(byte[] bufferTx, byte[] bufferRx, int length, int timeout) Write and read the requested bytes through the SPI port and store them in the given buffer.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

MAX_FRAME_SIZE

public static final int MAX_FRAME_SIZE

See Also:

Constant Field Values

MAX_TIMEOUT

public static final int MAX_TIMEOUT

See Also:

Constant Field Values

SPI_POL0_PHA0

public static final int SPI_POL0_PHA0

See Also:

Constant Field Values

SPI_POL0_PHA1

public static final int SPI_POL0_PHA1

See Also:

Constant Field Values

SPI_POL1_PHA0

public static final int SPI_POL1_PHA0

See Also:

Constant Field Values

SPI_POL1_PHA1

public static final int SPI_POL1_PHA1

See Also:

Constant Field Values

NO_CS

public static final int NO_CS

See Also:

Constant Field Values

HAS_CS

public static final int HAS_CS

See Also:

Constant Field Values

Constructor Detail

Spi

public Spi(int spiFrequency,
           int spiMode,
           int spiUseCs)

Creates a Master Spi interface at the specified frequency.

Parameters:

spiFrequency - the frequency of the SPI clock

spiMode - the polarity and the phase of the SPI (should 0,1,2 or 3.

spiUseCs - 1 when the /CS pin is used, 0 when it is not connected

Spi

public Spi(int target,
           int spiFrequency,
           int spiMode,
           int spiUseCs)

Creates a Master Spi interface at the specified frequency.

Parameters:

target -

spiFrequency - the frequency of the SPI clock

spiMode - the polarity and the phase of the SPI (should 0,1,2 or 3.

spiUseCs - 1 when the /CS pin is used, 0 when it is not connected

Method Detail

writeReadBytes

public int writeReadBytes(byte[] bufferTx,
                          byte[] bufferRx,
                          int length,
                          int timeout)

Write and read the requested bytes through the SPI port and store them in the given buffer.

Parameters:

buffer - the buffer that will receive the data

length - the number of bytes to read

timeout - (used when usecs==1)

Returns:

the length of the received byte buffer (max of length and buffer.length)

readBytes

public int readBytes(byte[] buffer,
                     int length,
                     int timeout)

Read the requested bytes through the SPI port and store them in the given buffer.

Parameters:

buffer - the buffer that will receive the data

length - the number of bytes to read

timeout - (used when usecs==1)

Returns:

the length of the received byte buffer (max of length and buffer.length)

writeBytes

public int writeBytes(byte[] buffer,
                      int length,
                      int timeout)

Write the given buffer through the SPI port

Parameters:

buffer - the buffer to write

length - the number of bytes to write (should be less or equal to buffer.length)

timeout - (used when usecs==1)

Returns:

0 on completion

fill

public int fill(byte[] buffer,
                int numberOfTimes)

Sends the provided buffer repeatedly.

Parameters:

buffer -

numberOfTimes -

Returns:

sendBitMap

public int sendBitMap(byte[] bitmap,
                      int width,
                      int height,
                      int scaling,
                      short colorOn,
                      short colorOff)

Transforms the given bitmap, replacing every bit (MSB to LSB) by the corresponding colorOn / colorOff short value. This is used to send 2-color images (e.g. a QR Code) to 16-bit color display devices.

Parameters:

bitmap - Bitmap to send through SPI. Each bit of each byte, from most signifcant to least significant, are interpreted as consecutive pixels (on or off) of the output, left

width -

height -

scaling -

colorOn -

colorOff -

Returns: