xuartlite.h File Reference

#include "xil_types.h"
#include "xil_assert.h"
#include "xstatus.h"

Classes
struct	XUartLite_Stats
struct	XUartLite_Buffer
struct	XUartLite_Config
struct	XUartLite
Defines
#define	XUARTLITE_H
Typedefs
typedef void(*	XUartLite_Handler )(void *CallBackRef, unsigned int ByteCount)
Functions
int	XUartLite_Initialize (XUartLite *InstancePtr, u16 DeviceId)
XUartLite_Config *	XUartLite_LookupConfig (u16 DeviceId)
int	XUartLite_CfgInitialize (XUartLite InstancePtr, XUartLite_Config Config, u32 EffectiveAddr)
void	XUartLite_ResetFifos (XUartLite *InstancePtr)
unsigned int	XUartLite_Send (XUartLite InstancePtr, u8 DataBufferPtr, unsigned int NumBytes)
unsigned int	XUartLite_Recv (XUartLite InstancePtr, u8 DataBufferPtr, unsigned int NumBytes)
int	XUartLite_IsSending (XUartLite *InstancePtr)
void	XUartLite_GetStats (XUartLite InstancePtr, XUartLite_Stats StatsPtr)
void	XUartLite_ClearStats (XUartLite *InstancePtr)
int	XUartLite_SelfTest (XUartLite *InstancePtr)
void	XUartLite_EnableInterrupt (XUartLite *InstancePtr)
void	XUartLite_DisableInterrupt (XUartLite *InstancePtr)
void	XUartLite_SetRecvHandler (XUartLite InstancePtr, XUartLite_Handler FuncPtr, void CallBackRef)
void	XUartLite_SetSendHandler (XUartLite InstancePtr, XUartLite_Handler FuncPtr, void CallBackRef)
void	XUartLite_InterruptHandler (XUartLite *InstancePtr)

Detailed Description

Define Documentation

#define XUARTLITE_H

Typedef Documentation

typedef void(* XUartLite_Handler)(void *CallBackRef, unsigned int ByteCount)

Callback function. The first argument is a callback reference passed in by the upper layer when setting the callback functions, and passed back to the upper layer when the callback is invoked. The second argument is the ByteCount which is the number of bytes that actually moved from/to the buffer provided in the _Send/_Receive call.

Function Documentation

int XUartLite_CfgInitialize	(	XUartLite *	InstancePtr,
		XUartLite_Config *	Config,
		u32	EffectiveAddr
	)

Initialize a XUartLite instance. The receive and transmit FIFOs of the UART are not flushed, so the user may want to flush them. The hardware device does not have any way to disable the receiver such that any valid data may be present in the receive FIFO. This function disables the UART interrupt. The baudrate and format of the data are fixed in the hardware at hardware build time.

Parameters:

	InstancePtr	is a pointer to the XUartLite instance.
	Config	is a reference to a structure containing information about a specific UART Lite device. This function initializes an InstancePtr object for a specific device specified by the contents of Config. This function can initialize multiple instance objects with the use of multiple calls giving different Config information on each call.
	EffectiveAddr	is the device base address in the virtual memory address space. The caller is responsible for keeping the address mapping from EffectiveAddr to the device physical base address unchanged once this function is invoked. Unexpected errors may occur if the address mapping changes after this function is called. If address translation is not used, use Config->BaseAddress for this parameters, passing the physical address instead.

Returns:

XST_SUCCESS if everything starts up as expected.

Note:: The Config pointer argument is not used by this function, but is provided to keep the function signature consistent with other drivers.

void XUartLite_ClearStats ( XUartLite * InstancePtr )

This function zeros the statistics for the given instance.

Parameters:

InstancePtr

is a pointer to the XUartLite instance.

Returns:: None.

Note:: None.

void XUartLite_DisableInterrupt ( XUartLite * InstancePtr )

This function disables the UART interrupt. After calling this function, data may still be received by the UART but no interrupt will be generated since the hardware device has no way to disable the receiver.

Parameters:

InstancePtr

is a pointer to the XUartLite instance.

Returns:: None.

Note:: None.

void XUartLite_EnableInterrupt ( XUartLite * InstancePtr )

This function enables the UART interrupt such that an interrupt will occur when data is received or data has been transmitted. The device contains 16 byte receive and transmit FIFOs such that an interrupt is generated anytime there is data in the receive FIFO and when the transmit FIFO transitions from not empty to empty.

Parameters:

InstancePtr

is a pointer to the XUartLite instance.

Returns:: None.

Note:: None.

void XUartLite_GetStats	(	XUartLite *	InstancePtr,
		XUartLite_Stats *	StatsPtr
	)

Returns a snapshot of the current statistics in the structure specified.

Parameters:

	InstancePtr	is a pointer to the XUartLite instance.
	StatsPtr	is a pointer to a XUartLiteStats structure to where the statistics are to be copied.

Returns:: None.

Note:: None.

int XUartLite_Initialize	(	XUartLite *	InstancePtr,
		u16	DeviceId
	)

Initialize a XUartLite instance. The receive and transmit FIFOs of the UART are not flushed, so the user may want to flush them. The hardware device does not have any way to disable the receiver such that any valid data may be present in the receive FIFO. This function disables the UART interrupt. The baudrate and format of the data are fixed in the hardware at hardware build time.

Parameters:

	InstancePtr	is a pointer to the XUartLite instance.
	DeviceId	is the unique id of the device controlled by this XUartLite instance. Passing in a device id associates the generic XUartLite instance to a specific device, as chosen by the caller or application developer.

Returns:

XST_SUCCESS if everything starts up as expected.
XST_DEVICE_NOT_FOUND if the device is not found in the configuration table.

Note:: None.

void XUartLite_InterruptHandler ( XUartLite * InstancePtr )

This function is the interrupt handler for the UART lite driver. It must be connected to an interrupt system by the user such that it is called when an interrupt for any UART lite occurs. This function does not save or restore the processor context such that the user must ensure this occurs.

Parameters:

InstancePtr

contains a pointer to the instance of the UART that the interrupt is for.

Returns:: None.

Note:: None.

int XUartLite_IsSending ( XUartLite * InstancePtr )

This function determines if the specified UART is sending data. If the transmitter register is not empty, it is sending data.

Parameters:

InstancePtr

is a pointer to the XUartLite instance.

Returns:: A value of TRUE if the UART is sending data, otherwise FALSE.

Note:: None.

XUartLite_Config* XUartLite_LookupConfig ( u16 DeviceId )

unsigned int XUartLite_Recv	(	XUartLite *	InstancePtr,
		u8 *	DataBufferPtr,
		unsigned int	NumBytes
	)

This function will attempt to receive a specified number of bytes of data from the UART and store it into the specified buffer. This function is designed for either polled or interrupt driven modes. It is non-blocking such that it will return if no data has already received by the UART.

In a polled mode, this function will only receive as much data as the UART can buffer in the FIFO. The application may need to call it repeatedly to receive a buffer. Polled mode is the default mode of operation for the driver.

In interrupt mode, this function will start receiving and then the interrupt handler of the driver will continue receiving data until the buffer has been received. A callback function, as specified by the application, will be called to indicate the completion of receiving the buffer or when any receive errors or timeouts occur.

Parameters:

	InstancePtr	is a pointer to the XUartLite instance.
	DataBufferPtr	is pointer to buffer for data to be received into.
	NumBytes	is the number of bytes to be received. A value of zero will stop a previous receive operation that is in progress in interrupt mode.

Returns:: The number of bytes received.

Note:: The number of bytes is not asserted so that this function may be called with a value of zero to stop an operation that is already in progress.

void XUartLite_ResetFifos ( XUartLite * InstancePtr )

This function resets the FIFOs, both transmit and receive, of the UART such that they are emptied. Since the UART does not have any way to disable it from receiving data, it may be necessary for the application to reset the FIFOs to get rid of any unwanted data.

Parameters:

InstancePtr

is a pointer to the XUartLite instance .

Returns:: None.

Note:: None.

int XUartLite_SelfTest ( XUartLite * InstancePtr )

Runs a self-test on the device hardware. Since there is no way to perform a loopback in the hardware, this test can only check the state of the status register to verify it is correct. This test assumes that the hardware device is still in its reset state, but has been initialized with the Initialize function.

Parameters:

InstancePtr

is a pointer to the XUartLite instance.

Returns:

XST_SUCCESS if the self-test was successful.
XST_FAILURE if the self-test failed, the status register value was not correct

Note:: None.

unsigned int XUartLite_Send	(	XUartLite *	InstancePtr,
		u8 *	DataBufferPtr,
		unsigned int	NumBytes
	)

This functions sends the specified buffer of data using the UART in either polled or interrupt driven modes. This function is non-blocking such that it will return before the data has been sent by the UART. If the UART is busy sending data, it will return and indicate zero bytes were sent.

In a polled mode, this function will only send as much data as the UART can buffer in the FIFO. The application may need to call it repeatedly to send a buffer.

In interrupt mode, this function will start sending the specified buffer and then the interrupt handler of the driver will continue sending data until the buffer has been sent. A callback function, as specified by the application, will be called to indicate the completion of sending the buffer.

Parameters:

	InstancePtr	is a pointer to the XUartLite instance.
	DataBufferPtr	is pointer to a buffer of data to be sent.
	NumBytes	contains the number of bytes to be sent. A value of zero will stop a previous send operation that is in progress in interrupt mode. Any data that was already put into the transmit FIFO will be sent.

Returns:: The number of bytes actually sent.

Note:: The number of bytes is not asserted so that this function may be called with a value of zero to stop an operation that is already in progress.

void XUartLite_SetRecvHandler	(	XUartLite *	InstancePtr,
		XUartLite_Handler	FuncPtr,
		void *	CallBackRef
	)

This function sets the handler that will be called when an event (interrupt) occurs in the driver. The purpose of the handler is to allow application specific processing to be performed.

Parameters:

	InstancePtr	is a pointer to the XUartLite instance.
	FuncPtr	is the pointer to the callback function.
	CallBackRef	is the upper layer callback reference passed back when the callback function is invoked.

Returns:: None.

Note:: There is no assert on the CallBackRef since the driver doesn't know what it is (nor should it)

void XUartLite_SetSendHandler	(	XUartLite *	InstancePtr,
		XUartLite_Handler	FuncPtr,
		void *	CallBackRef
	)

This function sets the handler that will be called when an event (interrupt) occurs in the driver. The purpose of the handler is to allow application specific processing to be performed.

Parameters:

	InstancePtr	is a pointer to the XUartLite instance .
	FuncPtr	is the pointer to the callback function.
	CallBackRef	is the upper layer callback reference passed back when the callback function is invoked.

Returns:: None.

Note:: There is no assert on the CallBackRef since the driver doesn't know what it is (nor should it)

Xilinx Processor IP Library

xuartlite.h File Reference

Classes

Defines

Typedefs

Functions

Detailed Description

Define Documentation

Typedef Documentation

Function Documentation