MicroC-OS-II running on Microblaze with UARTLITE in interrupt mode not working

Question

Hello, 
I am trying to write and application that uses the MicroBlaze which runs the MicroC-OS-II. I am also trying to use the UARTLITE in interrupt mode. 
Currently I can use the UARTLITE in interrrupt mode if I run a standalone package that is without MicroC-OS-II.m
I read the documentation attached see page 22 (Handling Interrupts). On how the OS handles interrupts but I am little confused on how to setup the UARTLITE in interrrupt mode to work with the OS.
I know that OS_CPU_ISR() handles the interrupt but how do I make it so that it handles the uartlite interrupt. 
I am really confused how I should modify the UARTLITE interrupt code below to work with MICROC/OS. As really confused I MEAN I JUST DON"T understand. 
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* @file xuartlite_intr_example.c
* This file contains a design example using the UartLite driver (XUartLite) and
* hardware device using the interrupt mode.
* @note
* The user must provide a physical loopback such that data which is
* transmitted will be received.
* MODIFICATION HISTORY:
* <pre>
* Ver Who Date Changes
* 1.00a jhl 02/13/02 First release
* 1.00b rpm 10/01/03 Made XIntc declaration global
* 1.00b sv 06/09/05 Minor changes to comply to Doxygen and coding guidelines
* 2.00a ktn 10/20/09 Updated to use HAL Processor APIs and minor changes
* for coding guidelnes.
* </pre>
/***************************** Include Files *********************************/
#include "xparameters.h"
#include "xuartlite.h"
#include "xintc.h"
#include "xil_exception.h"
/************************** Constant Definitions *****************************/
* The following constants map to the XPAR parameters created in the
* xparameters.h file. They are defined here such that a user can easily
* change all the needed parameters in one place.
#define UARTLITE_DEVICE_ID XPAR_UARTLITE_2_DEVICE_ID
#define INTC_DEVICE_ID XPAR_INTC_0_DEVICE_ID
#define UARTLITE_INT_IRQ_ID XPAR_INTC_0_UARTLITE_2_VEC_ID
* The following constant controls the length of the buffers to be sent
* and received with the UartLite device.
#define TEST_BUFFER_SIZE 100
/**************************** Type Definitions *******************************/
/***************** Macros (Inline Functions) Definitions *********************/
/************************** Function Prototypes ******************************/
int UartLiteIntrExample(u16 DeviceId);
int SetupInterruptSystem(XUartLite *UartLitePtr);
void SendHandler(void *CallBackRef, unsigned int EventData);
void RecvHandler(void *CallBackRef, unsigned int EventData);
/************************** Variable Definitions *****************************/
XUartLite UartLite; /* The instance of the UartLite Device */
XIntc InterruptController; /* The instance of the Interrupt Controller */
* The following variables are shared between non-interrupt processing and
* interrupt processing such that they must be global.
* The following buffers are used in this example to send and receive data
* with the UartLite.
u8 SendBuffer[TEST_BUFFER_SIZE];
u8 ReceiveBuffer[TEST_BUFFER_SIZE];
* The following counters are used to determine when the entire buffer has
* been sent and received.
static volatile int TotalReceivedCount;
static volatile int TotalSentCount;
* Main function to call the UartLite interrupt example.
* @param None
* @return XST_SUCCESS if successful, XST_FAILURE if unsuccessful
* @note None
int main(void)
int Status;
xil_printf("Started\n");
* Run the UartLite Interrupt example, specify the Device ID that is
* generated in xparameters.h.
Status = UartLiteIntrExample(UARTLITE_DEVICE_ID);
if (Status != XST_SUCCESS) {
return XST_FAILURE;
return XST_SUCCESS;
* This function does a minimal test on the UartLite device and driver as a
* design example. The purpose of this function is to illustrate
* how to use the XUartLite component.
* This function sends data and expects to receive the same data through the
* UartLite. The user must provide a physical loopback such that data which is
* transmitted will be received.
* This function uses interrupt driver mode of the UartLite device. The calls
* to the UartLite driver in the handlers should only use the non-blocking
* calls.
* @param DeviceId is the Device ID of the UartLite Device and is the
* XPAR_<uartlite_instance>_DEVICE_ID value from xparameters.h.
* @return XST_SUCCESS if successful, otherwise XST_FAILURE.
* @note
* This function contains an infinite loop such that if interrupts are not
* working it may never return.
int UartLiteIntrExample(u16 DeviceId)
int Status;
int Index;
* Initialize the UartLite driver so that it's ready to use.
Status = XUartLite_Initialize(&UartLite, DeviceId);
if (Status != XST_SUCCESS) {
return XST_FAILURE;
* Perform a self-test to ensure that the hardware was built correctly.
Status = XUartLite_SelfTest(&UartLite);
if (Status != XST_SUCCESS) {
return XST_FAILURE;
* Connect the UartLite to the interrupt subsystem such that interrupts can
* occur. This function is application specific.
Status = SetupInterruptSystem(&UartLite);
if (Status != XST_SUCCESS) {
return XST_FAILURE;
* Setup the handlers for the UartLite that will be called from the
* interrupt context when data has been sent and received, specify a
* pointer to the UartLite driver instance as the callback reference so
* that the handlers are able to access the instance data.
XUartLite_SetSendHandler(&UartLite, SendHandler, &UartLite);
XUartLite_SetRecvHandler(&UartLite, RecvHandler, &UartLite);
* Enable the interrupt of the UartLite so that interrupts will occur.
XUartLite_EnableInterrupt(&UartLite);
* Initialize the send buffer bytes with a pattern to send and the
* the receive buffer bytes to zero to allow the receive data to be
* verified.
for (Index = 0; Index < TEST_BUFFER_SIZE; Index++) {
SendBuffer[Index] = Index;
ReceiveBuffer[Index] = 0;
* Start receiving data before sending it since there is a loopback.
XUartLite_Recv(&UartLite, ReceiveBuffer, TEST_BUFFER_SIZE);
* Send the buffer using the UartLite.
XUartLite_Send(&UartLite, SendBuffer, TEST_BUFFER_SIZE);
* Wait for the entire buffer to be received, letting the interrupt
* processing work in the background, this function may get locked
* up in this loop if the interrupts are not working correctly.
while ((TotalReceivedCount != TEST_BUFFER_SIZE) ||
(TotalSentCount != TEST_BUFFER_SIZE)) {
for (Index = 0; Index < TEST_BUFFER_SIZE; Index++)
xil_printf("%d",ReceiveBuffer[Index]);
* Verify the entire receive buffer was successfully received.
for (Index = 0; Index < TEST_BUFFER_SIZE; Index++) {
if (ReceiveBuffer[Index] != SendBuffer[Index]) {
return XST_FAILURE;
return XST_SUCCESS;
* This function is the handler which performs processing to send data to the
* UartLite. It is called from an interrupt context such that the amount of
* processing performed should be minimized. It is called when the transmit
* FIFO of the UartLite is empty and more data can be sent through the UartLite.
* This handler provides an example of how to handle data for the UartLite,
* but is application specific.
* @param CallBackRef contains a callback reference from the driver.
* In this case it is the instance pointer for the UartLite driver.
* @param EventData contains the number of bytes sent or received for sent
* and receive events.
* @return None.
* @note None.
void SendHandler(void *CallBackRef, unsigned int EventData)
TotalSentCount = EventData;
* This function is the handler which performs processing to receive data from
* the UartLite. It is called from an interrupt context such that the amount of
* processing performed should be minimized. It is called data is present in
* the receive FIFO of the UartLite such that the data can be retrieved from
* the UartLite. The size of the data present in the FIFO is not known when
* this function is called.
* This handler provides an example of how to handle data for the UartLite,
* but is application specific.
* @param CallBackRef contains a callback reference from the driver, in
* this case it is the instance pointer for the UartLite driver.
* @param EventData contains the number of bytes sent or received for sent
* and receive events.
* @return None.
* @note None.
void RecvHandler(void *CallBackRef, unsigned int EventData)
TotalReceivedCount = EventData;
* This function setups the interrupt system such that interrupts can occur
* for the UartLite device. This function is application specific since the
* actual system may or may not have an interrupt controller. The UartLite
* could be directly connected to a processor without an interrupt controller.
* The user should modify this function to fit the application.
* @param UartLitePtr contains a pointer to the instance of the UartLite
* component which is going to be connected to the interrupt
* controller.
* @return XST_SUCCESS if successful, otherwise XST_FAILURE.
* @note None.
int SetupInterruptSystem(XUartLite *UartLitePtr)
int Status;
* Initialize the interrupt controller driver so that it is ready to
* use.
Status = XIntc_Initialize(&InterruptController, INTC_DEVICE_ID);
if (Status != XST_SUCCESS) {
return XST_FAILURE;
* Connect a device driver handler that will be called when an interrupt
* for the device occurs, the device driver handler performs the
* specific interrupt processing for the device.
Status = XIntc_Connect(&InterruptController, UARTLITE_INT_IRQ_ID,
(XInterruptHandler)XUartLite_InterruptHandler,
(void *)UartLitePtr);
if (Status != XST_SUCCESS) {
return XST_FAILURE;
* Start the interrupt controller such that interrupts are enabled for
* all devices that cause interrupts, specific real mode so that
* the UartLite can cause interrupts through the interrupt controller.
Status = XIntc_Start(&InterruptController, XIN_REAL_MODE);
if (Status != XST_SUCCESS) {
return XST_FAILURE;
* Enable the interrupt for the UartLite device.
XIntc_Enable(&InterruptController, UARTLITE_INT_IRQ_ID);
* Initialize the exception table.
Xil_ExceptionInit();
* Register the interrupt controller handler with the exception table.
Xil_ExceptionRegisterHandler(XIL_EXCEPTION_ID_INT,
(Xil_ExceptionHandler)XIntc_InterruptHandler,
&InterruptController);
* Enable exceptions.
Xil_ExceptionEnable();
return XST_SUCCESS;
 

Answer 1

Hello,
I have a KC705 board, with Microblaze on it. My software is Witten above the operating system of µC/OS-II.I am trying to write multi task ie. task1 and task2.  Application that uses the MicroBlaze which runs the MicroC-OS-II.
I am using  the UARTLITE able to run hello world program successfully is with MicroC-OS-II.I read the documentations,  On how the OS handles multi task, but I am little confused on how to implement..(i am new to RTOS). Please suggest  me or share the any documents, any example codes.
~thanks
ASHIOK H