SPI

java.lang.Object
- com.digi.android.spi.SPI

```
public class SPI
extends java.lang.Object
```
This class allows the user to manage SPI devices. This interaction is performed via the corresponding native library that interfaces directly with the kernel.
Each object of this class is created for a determined SPI interface and SPI slave device.

To obtain an instance of the SPI interface you have to use the SPIManager.createSPI(int, int) method.

Field Summary

Fields
Modifier and Type	Field	Description
`static int`	`CPHA_CONFIG`	Clock line phase:
`static int`	`CPOL_CONFIG`	Clock line polarity:
`static int`	`CS_HIGH_CONFIG`	Chip select line active high:
`static int`	`CS_LOW_CONFIG`	Chip select line active low:
`static int`	`LOOP_CONFIG`	Loopback mode:
`static int`	`LSB_FIRST_CONFIG`	Message bit order (LSB first):
`static int`	`MODE_0`	MODE_0 (0x00) -> Clock polarity = 0 / Clock phase = 0
`static int`	`MODE_1`	MODE_1 (0x01) -> Clock polarity = 0 / Clock phase = 1
`static int`	`MODE_2`	MODE_2 (0x02) -> Clock polarity = 1 / Clock phase = 0
`static int`	`MODE_3`	MODE_3 (0x03) -> Clock polarity = 1 / Clock phase = 1
`static int`	`MSB_FIRST_CONFIG`	Message bit order (MSB first):
`static int`	`NO_CS_CONFIG`	No chip select mode:
`static int`	`READY_CONFIG`	Ready mode (slave pulls low to pause):
`static int`	`THREE_WIRE_CONFIG`	3 wire mode:

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`close()`	Attempts to close the SPI interface.
`protected void`	`finalize()`
`SPIConfig`	`getConfig()`	Gets the SPI configuration.
`int`	`getInterface()`	Gets the SPI interface number.
`int`	`getSlaveDevice()`	Gets the SPI slave device number.
`boolean`	`isInterfaceOpen()`	Gets the status of the SPI interface.
`void`	`open(SPIConfig config)`	Opens the SPI interface with the given configuration.
`byte[]`	`read(int numBytes)`	Reads the specified number of bytes from the SPI slave device.
`void`	`setConfig(SPIConfig config)`	Changes the configuration of the SPI.
`byte[]`	`transfer(byte[] txData)`	Simultaneous write (of the given bytes) and read (of the same number of bytes) using the default clock frequency and word length parameters.
`byte[]`	`transfer(byte[] txData, int clockFrequency, int wordLength)`	Simultaneous write (of the given bytes) and read (of the same number of bytes) using the given clock frequency and word length parameters (these parameters are only used for this transfer, but their default values remain the same).
`void`	`write(byte[] txData)`	Writes the given bytes in the SPI slave device.

Methods inherited from class java.lang.Object
clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - CPHA_CONFIG
```
public static final int CPHA_CONFIG
```
    Clock line phase:
    
    See Also:
    
    Constant Field Values
  - CPOL_CONFIG
```
public static final int CPOL_CONFIG
```
    Clock line polarity:
    
    See Also:
    
    Constant Field Values
  - CS_LOW_CONFIG
```
public static final int CS_LOW_CONFIG
```
    Chip select line active low:
    
    See Also:
    
    Constant Field Values
  - CS_HIGH_CONFIG
```
public static final int CS_HIGH_CONFIG
```
    Chip select line active high:
    
    See Also:
    
    Constant Field Values
  - MSB_FIRST_CONFIG
```
public static final int MSB_FIRST_CONFIG
```
    Message bit order (MSB first):
    
    See Also:
    
    Constant Field Values
  - LSB_FIRST_CONFIG
```
public static final int LSB_FIRST_CONFIG
```
    Message bit order (LSB first):
    
    See Also:
    
    Constant Field Values
  - THREE_WIRE_CONFIG
```
public static final int THREE_WIRE_CONFIG
```
    3 wire mode:
    
    See Also:
    
    Constant Field Values
  - LOOP_CONFIG
```
public static final int LOOP_CONFIG
```
    Loopback mode:
    
    See Also:
    
    Constant Field Values
  - NO_CS_CONFIG
```
public static final int NO_CS_CONFIG
```
    No chip select mode:
    
    See Also:
    
    Constant Field Values
  - READY_CONFIG
```
public static final int READY_CONFIG
```
    Ready mode (slave pulls low to pause):
    
    See Also:
    
    Constant Field Values
  - MODE_0
```
public static final int MODE_0
```
    MODE_0 (0x00) -> Clock polarity = 0 / Clock phase = 0
    
    See Also:
    
    Constant Field Values
  - MODE_1
```
public static final int MODE_1
```
    MODE_1 (0x01) -> Clock polarity = 0 / Clock phase = 1
    
    See Also:
    
    Constant Field Values
  - MODE_2
```
public static final int MODE_2
```
    MODE_2 (0x02) -> Clock polarity = 1 / Clock phase = 0
    
    See Also:
    
    Constant Field Values
  - MODE_3
```
public static final int MODE_3
```
    MODE_3 (0x03) -> Clock polarity = 1 / Clock phase = 1
    
    See Also:
    
    Constant Field Values
- Method Detail
  - open
```
public void open(SPIConfig config)
          throws NoSuchInterfaceException,
                 java.io.IOException
```
    Opens the SPI interface with the given configuration.
    
    Parameters:
    
    config - SPI configuration.
    
    Throws:
    
    java.io.IOException - If there is an error opening the SPI interface.
    
    NoSuchInterfaceException - If the configured SPI interface does not exist.
    
    java.lang.NullPointerException - If config == null.
    
    See Also:
    
    close(), isInterfaceOpen(), SPIConfig
  - close
```
public void close()
           throws java.io.IOException
```
    Attempts to close the SPI interface.
    
    Throws:
    
    java.io.IOException - If there is an error closing the SPI interface.
    
    See Also:
    
    isInterfaceOpen(), open(SPIConfig)
  - isInterfaceOpen
```
public boolean isInterfaceOpen()
```
    Gets the status of the SPI interface.
    
    Returns:
    
    true if interface is open, false if not.
    
    See Also:
    
    close(), open(SPIConfig)
  - setConfig
```
public void setConfig(SPIConfig config)
               throws java.io.IOException
```
    Changes the configuration of the SPI.
    
    Parameters:
    
    config - New SPI configuration.
    
    Throws:
    
    java.io.IOException - If the interface is closed or there is an error changing the configuration.
    
    java.lang.NullPointerException - If config == null.
    
    See Also:
    
    getConfig(), isInterfaceOpen(), open(SPIConfig), SPIConfig
  - getConfig
```
public SPIConfig getConfig()
```
    Gets the SPI configuration.
    
    Returns:
    
    The SPI configuration.
    
    See Also:
    
    setConfig(SPIConfig), SPIConfig
  - getInterface
```
public int getInterface()
```
    Gets the SPI interface number.
    
    Returns:
    
    The SPI interface in use.
  - getSlaveDevice
```
public int getSlaveDevice()
```
    Gets the SPI slave device number.
    
    Returns:
    
    The SPI slave device.
  - read
```
public byte[] read(int numBytes)
            throws java.io.IOException
```
    Reads the specified number of bytes from the SPI slave device.
    
    Parameters:
    
    numBytes - Amount of bytes to read.
    
    Returns:
    
    The read bytes, null if error.
    
    Throws:
    
    java.lang.IllegalArgumentException - If numBytes < 0.
    
    java.io.IOException - If the interface is closed or there is an error reading from the SPI slave device.
    
    See Also:
    
    isInterfaceOpen(), open(SPIConfig)
  - write
```
public void write(byte[] txData)
           throws java.io.IOException
```
    Writes the given bytes in the SPI slave device.
    
    Parameters:
    
    txData - Bytes to write.
    
    Throws:
    
    java.io.IOException - If the interface is closed or there is an error writing in the SPI slave device.
    
    java.lang.NullPointerException - If txData == null.
    
    See Also:
    
    isInterfaceOpen(), open(SPIConfig)
  - transfer
```
public byte[] transfer(byte[] txData)
                throws java.io.IOException
```
    Simultaneous write (of the given bytes) and read (of the same number of bytes) using the default clock frequency and word length parameters.
    
    Parameters:
    
    txData - Bytes to write.
    
    Returns:
    
    The read bytes, null if error.
    
    Throws:
    
    java.io.IOException - If the interface is closed or there is an error transferring data.
    
    java.lang.NullPointerException - If txData == null.
    
    See Also:
    
    getConfig(), isInterfaceOpen(), transfer(byte[], int, int)
  - transfer
```
public byte[] transfer(byte[] txData,
                       int clockFrequency,
                       int wordLength)
                throws java.io.IOException
```
    Simultaneous write (of the given bytes) and read (of the same number of bytes) using the given clock frequency and word length parameters (these parameters are only used for this transfer, but their default values remain the same).
    
    Parameters:
    
    txData - Bytes to write.
    
    clockFrequency - The clock frequency in Hz.
    
    wordLength - Number of bits per word.
    
    Returns:
    
    The read bytes, null if error.
    
    Throws:
    
    java.lang.IllegalArgumentException - If clockFrequency < 1 o if wordLength < 1.
    
    java.io.IOException - If the interface is closed or there is an error transferring data.
    
    java.lang.NullPointerException - If txData == null.
    
    See Also:
    
    getConfig(), isInterfaceOpen(), transfer(byte[]), SPIConfig.getClockFrequency(), SPIConfig.getWordLength()
  - finalize
```
protected void finalize()
                 throws java.lang.Throwable
```
    Overrides:
    
    finalize in class java.lang.Object
    
    Throws:
    
    java.lang.Throwable

Class SPI

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

CPHA_CONFIG

CPOL_CONFIG

CS_LOW_CONFIG

CS_HIGH_CONFIG

MSB_FIRST_CONFIG

LSB_FIRST_CONFIG

THREE_WIRE_CONFIG

LOOP_CONFIG

NO_CS_CONFIG

READY_CONFIG

MODE_0

MODE_1

MODE_2

MODE_3

Method Detail

open

close

isInterfaceOpen

setConfig

getConfig

getInterface

getSlaveDevice

read

write

transfer

transfer

finalize