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shijiluoben
Observer
Observer
8,172 Views
Registered: ‎04-10-2008

Emac receive fifo

I connected a loopback wire to my emac and sent a package and tried to retrieve it through receive fifo. It showed package was sent correctly but when I tried to retrieve the package, the fifo showed no data. No data loss or colision was found. Both pull mode and interrupt mode without dma were tried.

 

Anybody has any idea? Is my receive fifo closed? otherwise the receive fifo should not be empty.

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5 Replies
shijiluoben
Observer
Observer
8,141 Views
Registered: ‎04-10-2008

Still not solved. can anyone help?
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vsiva
Xilinx Employee
Xilinx Employee
8,126 Views
Registered: ‎01-18-2008

Your post is missing a number of details. Please post the IP you use (sounds like it is opb_ethernet, but it could also be xps_ethernetlite), EDK version you are using, etc.

 

I'd suggest that you build a simple system using BSB, and then check whether TestApp_Peripheral works fine. The Ethernet testapp pretty much does what you are doing: set the mac in loopback, and send & receive a packet. If it succeeds, then you know your hardware is ok, and then you can look at your software. 

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shijiluoben
Observer
Observer
8,111 Views
Registered: ‎04-10-2008

Thanks, vsiva.

 

I am using EDK 9.1i sp2 and ISE 9.1i sp3. IP is opb_ethernet.

I can run the self-loop successfully. The hardware should be ok because I can run a webserver design when virtex board communicate with PC.

 

For the software, I modified the xemac_intr_fifo_example.c of the Emac driver. I only changed the destination address and removed the loopback option.

 

Now I am trying to communicate with another board which should have no problem. I send some frames to it and the it send them back. It can receive my frame but I can not receive when it sent back.

By the way, I also tried to use a loopback ethernet cable(the send line and receive line are soldered together), it showed that the green lights on the MAC ports were even not turned on after I implemented the design. 

Message Edited by shijiluoben on 05-13-2008 07:59 AM
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vsiva
Xilinx Employee
Xilinx Employee
8,098 Views
Registered: ‎01-18-2008

If the webserver design works, that implies that you can both send & receive packets to another host. So either your modifications to xemac_intr_fifo_example.c are wrong, or when you send frames from a different host, they might not be in the correct format, and opb_ethernet could be discarding it (maybe the address doesn't match..).

 

I'm not sure about using a loopback cable, I don't know if that would even work. But you have to make sure that the LED's are on when it is connected to a different host.  

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shijiluoben
Observer
Observer
8,087 Views
Registered: ‎04-10-2008

Could you take a look at my modification? Thx a lot!

The removed parts are marked blue and the added parts are marked red. 

 

/* $Id: xemac_intr_fifo_example.c,v 1.5 2006/06/26 23:07:17 somn Exp $ */
/******************************************************************************
*
*       XILINX IS PROVIDING THIS DESIGN, CODE, OR INFORMATION "AS IS"
*       AS A COURTESY TO YOU, SOLELY FOR USE IN DEVELOPING PROGRAMS AND
*       SOLUTIONS FOR XILINX DEVICES.  BY PROVIDING THIS DESIGN, CODE,
*       OR INFORMATION AS ONE POSSIBLE IMPLEMENTATION OF THIS FEATURE,
*       APPLICATION OR STANDARD, XILINX IS MAKING NO REPRESENTATION
*       THAT THIS IMPLEMENTATION IS FREE FROM ANY CLAIMS OF INFRINGEMENT,
*       AND YOU ARE RESPONSIBLE FOR OBTAINING ANY RIGHTS YOU MAY REQUIRE
*       FOR YOUR IMPLEMENTATION.  XILINX EXPRESSLY DISCLAIMS ANY
*       WARRANTY WHATSOEVER WITH RESPECT TO THE ADEQUACY OF THE
*       IMPLEMENTATION, INCLUDING BUT NOT LIMITED TO ANY WARRANTIES OR
*       REPRESENTATIONS THAT THIS IMPLEMENTATION IS FREE FROM CLAIMS OF
*       INFRINGEMENT, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
*       FOR A PARTICULAR PURPOSE.
*
*       (c) Copyright 2004-2005 Xilinx Inc.
*       All rights reserved.
*
******************************************************************************/
/*****************************************************************************/
/**
* @file xemac_intr_fifo_example.c
*
* This file can be used as a standalone example of how to use the XEmac driver
* directly or by the TestAppGen utility to include a test for Emac interrupt in
* direct FIFO mode.
*
* The example here shows using the driver/device in interrupt mode with direct
* FIFO I/O.  This mode is typically not used when the device is configured with
* DMA. Standalone, this example works with a PPC405 processor. Refer the example
* of Interrupt Controller (XIntc) for using an Interrupt Controller with
* Microblaze processor.
*
* @note
*
* None
*
* <pre>
*
* MODIFICATION HISTORY:
*
* Ver   Who  Date     Changes
* ----- ---- -------- ---------------------------------------------------------
* 1.00a rbm  11/23/04 Initial release
* 1.00a sv   06/09/05 Minor changes to comply to Doxygen and coding guidelines
* 1.01a sn   05/09/06 Modified to be used by TestAppGen to include test for
*                     interrupts.
* </pre>
*
******************************************************************************/

/***************************** Include Files *********************************/

#include "xparameters.h"
#include "xemac.h"
#include "xintc.h"
#ifndef __MICROBLAZE__
#include "xexception_l.h"
#endif
/************************** 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.
 */
#ifndef TESTAPP_GEN
#define EMAC_DEVICE_ID          XPAR_ETHERNET_MAC_DEVICE_ID
#define INTC_DEVICE_ID          XPAR_OPB_INTC_0_DEVICE_ID
#define EMAC_IRPT_INTR          XPAR_OPB_INTC_0_ETHERNET_MAC_IP2INTC_IRPT_INTR
#endif

#define XEM_MAX_FRAME_SIZE_IN_WORDS ((XEM_MAX_FRAME_SIZE / sizeof(Xuint32)) + 1)

#define DEFAULT_OPTIONS      (XEM_UNICAST_OPTION | XEM_INSERT_PAD_OPTION | \
                              XEM_INSERT_FCS_OPTION | XEM_INSERT_ADDR_OPTION | \
                              XEM_OVWRT_ADDR_OPTION)

/*
 * The size of the Test Frame in Bytes
 */
#define EMAC_TEST_FRAME_SIZE       200

/**************************** Type Definitions *******************************/


/***************** Macros (Inline Functions) Definitions *********************/


/************************** Function Prototypes ******************************/

XStatus EmacIntrExample(XIntc *IntcInstancePtr,
                        XEmac *EmacInstancePtr,
                        Xuint16 EmacDeviceId,
                        Xuint16 EmacIntrId);

static XStatus LoopbackFrame(XEmac *EmacInstancePtr, Xuint32 PayloadSize);

static XStatus SendFrame(XEmac *EmacInstancePtr, Xuint32 PayloadSize,
                         Xuint8 *DestAddress);

static void FifoRecvHandler(void *CallBackRef);

static void FifoSendHandler(void *CallBackRef);

static void ErrorHandler(void *CallBackRef, XStatus Code);

static XStatus EmacSetupIntrSystem(XIntc *IntcInstancePtr,
                                   XEmac *EmacInstancePtr,
                                   Xuint16 EmacDeviceId,
                                   Xuint16 EmacIntrId);

static void EmacDisableIntrSystem(XIntc *IntcInstancePtr, Xuint16 EmacIntrId);

/************************** Variable Definitions *****************************/

/*
 * Set up valid local MAC address. The loopback test will use the
 * LocalAddress both as source and destination.
 */
static Xuint8 LocalAddress[XEM_MAC_ADDR_SIZE] =
{
    0xDA, 0xDA, 0xDA, 0xDA, 0xDA, 0xDA
};

static Xuint8 RemoteAddress[XEM_MAC_ADDR_SIZE]=
{
  0x5A, 0x5A, 0x5A, 0x5A, 0x5A, 0x5A  
};

 

static XEmac Emac;                  /*  An instance of the XEmac driver */
static XIntc InterruptController;   /*  An instance of the XIntc driver */
/*
 * These buffers need to be 32-bit aligned
 */
static Xuint32 TxFrame[XEM_MAX_FRAME_SIZE_IN_WORDS];
static Xuint32 RecvBuffer[XEM_MAX_FRAME_SIZE_IN_WORDS];

/*
 * Shared variables used to test the callbacks with the send/receive
 */
static int SentPayloadSize;             /* Outstanding frame length */
static XStatus LoopbackError;           /* Asynchronous error occurred */
volatile static Xboolean RecvDone;      /* Received a frame */
volatile static Xboolean SendDone;      /* Sent a frame */


/*****************************************************************************/
/**
* Main function to call the Emac Interrupt-FIFO example.
*
* @param    None
*
* @return   XST_SUCCESS if successful, XST_FAILURE if unsuccessful
*
* @note     None
*
******************************************************************************/
#ifndef TESTAPP_GEN
int main(void)
{
    XStatus Status;
   
    /*
     * Run the Emac Interrupt-FIFO example , specify the Device ID that is
     * generated in xparameters.h
     */
   
    Status = EmacIntrExample(&InterruptController,
                             &Emac,
                             EMAC_DEVICE_ID,
                             EMAC_IRPT_INTR);
   
   
    if (Status != XST_SUCCESS)
    {
        return XST_FAILURE;
    }
   
    return XST_SUCCESS;
   
}
#endif //TESTAPP_GEN

/******************************************************************************/
/**
*
* The main entry point for showing the XEmac driver in interrupt mode with
* FIFOs. The example configures the device for internal loopback mode, then
* sends an Ethernet frame and receives the same Ethernet frame.
*
* @param    IntcInstancePtr is the pointer to the instance of the INTC
*           component.
* @param    EmacInstancePtr is the pointer to the instance of the EMAC
*           component.
* @param    EmacDeviceId is the XPAR_<emac_instance>_DEVICE_ID value from
*           xparameters.h for EMAC
* @param    EmacIntrId is XPAR_<INTC_instance>_<EMAC_instance>_IP2INTC_IRPT_INTR
*           value from xparameters.h  
* @return   XST_SUCCESS if successful, otherwise XST_FAILURE
*
* @note     None.
*
******************************************************************************/

XStatus EmacIntrExample(XIntc *IntcInstancePtr,
                        XEmac *EmacInstancePtr,
                        Xuint16 EmacDeviceId,
                        Xuint16 EmacIntrId)
{

    XStatus Status;
    Xuint32 Options;
    XEmac_Config *ConfigPtr;

    /*
     * We change the configuration of the device to indicate no DMA just in
     * case it was built with DMA. In order for this example to work, you
     * either need to do this or, better yet, build the hardware without DMA.
     */
    ConfigPtr = XEmac_LookupConfig(EmacDeviceId);
    ConfigPtr->IpIfDmaConfig = XEM_CFG_NO_DMA;

    /*
     * Initialize the XEmac component. The device ID chosen should be
     * configured without DMA (see the xemac_g.c file)
     */
    Status = XEmac_Initialize(EmacInstancePtr, EmacDeviceId);
    if (Status != XST_SUCCESS)
    {
        return XST_FAILURE;
    }

    /*
     * We can check to be sure the device is confgured without DMA before
     * going on with the example.
     */
    if (XEmac_mIsDma(EmacInstancePtr))
    {
        /*
         * OOPS! it has DMA
         */
        return XST_FAILURE;
    }

    /*
     * Run self-test on the device, which verifies basic sanity of the
     * device and the driver.
     */
    Status = XEmac_SelfTest(EmacInstancePtr);
    if (Status != XST_SUCCESS)
    {
        return XST_FAILURE;
    }

    /*
     * First configure the device into loopback mode.  We also configure it
     * for unicast and broadcast addressing.
     */
    Options = (DEFAULT_OPTIONS | XEM_BROADCAST_OPTION);// LOOPBACK option is removed
    Status = XEmac_SetOptions(EmacInstancePtr, Options);
    if (Status != XST_SUCCESS)
    {
        return XST_FAILURE;
    }

    /*
     * Set the MAC address.
     */
    Status = XEmac_SetMacAddress(EmacInstancePtr, LocalAddress);
    if (Status != XST_SUCCESS)
    {
        return XST_FAILURE;
    }


    /*
     * Connect to the interrupt controller and enable interrupts
     */
    Status = EmacSetupIntrSystem(IntcInstancePtr,
                                 EmacInstancePtr,
                                 EmacDeviceId,
                                 EmacIntrId);
    if (Status != XST_SUCCESS)
    {
        return XST_FAILURE;
    }

    /*
     * Set the FIFO callbacks and error handler. These callbacks are invoked
     * by the driver during interrupt processing.
     */
    XEmac_SetFifoSendHandler(EmacInstancePtr, EmacInstancePtr, FifoSendHandler);
    XEmac_SetFifoRecvHandler(EmacInstancePtr, EmacInstancePtr, FifoRecvHandler);
    XEmac_SetErrorHandler(EmacInstancePtr, EmacInstancePtr, ErrorHandler);


    /*
     * Start the device, which enables the transmitter and receiver
     */
    Status = XEmac_Start(EmacInstancePtr);
    if (Status != XST_SUCCESS)
    {
        return XST_FAILURE;
    }

    /*
     * We clear the driver statistics so we can look at them later
     */
    XEmac_ClearStats(EmacInstancePtr);

    /*
     * Loopback a 200-byte frame (214 with the Ethernet header).
     */
    Status = LoopbackFrame(EmacInstancePtr, EMAC_TEST_FRAME_SIZE);
    if (Status != XST_SUCCESS)
    {
        return XST_FAILURE;
    }


    /*
     * Disable the EMAC interrupt
     */
    EmacDisableIntrSystem(IntcInstancePtr, EmacIntrId);

    return XST_SUCCESS;
}


/*****************************************************************************/
/**
*
* This function loopbacks a frame of given size. This function assumes interrupt
* mode and loopback mode and sends the frame. The FifoRecvHandler is expected to
* handle the received frame.
*
* @param    EmacInstancePtr is the pointer to the instance of the EMAC
*           component.
* @param    PayloadSize is the size of the frame to create. The size only
*           reflects the payload size, it does not include the Ethernet header
*           size (14 bytes) nor the Ethernet CRC size (4 bytes).
*
* @return   XST_SUCCESS if successful, otherwise XST_FAILURE
*
* @note     None.
*
******************************************************************************/
static XStatus LoopbackFrame(XEmac *EmacInstancePtr, Xuint32 PayloadSize)
{
    XStatus Status;

    SendDone = XFALSE;
    RecvDone = XFALSE;
    LoopbackError = XST_SUCCESS;

    SentPayloadSize = PayloadSize;

    Status = SendFrame(EmacInstancePtr, PayloadSize, RemoteAddress); // RemoteAddress replaced LocalAddress
    if (Status == XST_SUCCESS)
    {
        /*
         * Wait here until both send and receive have been completed
         */
        while (!SendDone || !RecvDone);

        /*
         * Check for errors found in the callbacks
         */
        if (LoopbackError != XST_SUCCESS)
        {
            return XST_FAILURE;
        }

        return XST_SUCCESS;
    }

    return XST_FAILURE;
}

/*****************************************************************************/
/**
* This functions sends an Ethernet frame of given size
*
* @param    EmacInstancePtr is the pointer to the instance of the EMAC
*           component.
* @param    PayloadSize is the size of the frame to create. The size only
*           reflects the payload size, it does not include the Ethernet header
*           size (14 bytes) nor the Ethernet CRC size (4 bytes).
* @param    DestAddress is the Destination Address
*
* @return   XST_SUCCESS if successful, else XST_FAILURE
*
* @note     None.
*
******************************************************************************/
static XStatus SendFrame(XEmac *EmacInstancePtr, Xuint32 PayloadSize,
                         Xuint8 *DestAddress)
{
    Xuint8 *FramePtr;
    Xuint8 *AddrPtr = DestAddress;
    int Index;

    /*
     * Assemble the frame with a destination address and a bogus source address
     * (the MAC overwrites it by default)
     */
    FramePtr = (Xuint8 *)TxFrame;

    *FramePtr++ = *AddrPtr++;
    *FramePtr++ = *AddrPtr++;
    *FramePtr++ = *AddrPtr++;
    *FramePtr++ = *AddrPtr++;
    *FramePtr++ = *AddrPtr++;
    *FramePtr++ = *AddrPtr++;

    FramePtr += XEM_MAC_ADDR_SIZE;  /* get past source address (bogus) */

    /*
     * Set up the type/length field - be sure its in network order
     */
    *((Xuint16 *)FramePtr) = PayloadSize;
    FramePtr++;
    FramePtr++;

    /*
     * Now fill in the data field with known values so we can verify them
     * on receive.
     */
    for (Index = 0; Index < PayloadSize; Index++)
    {
        *FramePtr++ = (Xuint8)Index;
    }

    /*
     * Now send the frame (payload and header)
     */
    return XEmac_FifoSend(EmacInstancePtr, (Xuint8 *)TxFrame,
                          PayloadSize + XEM_HDR_SIZE);
}


/*****************************************************************************/
/**
* This is the Callback function (called from driver) to handle frames received
* in direct memory-mapped I/O mode.  This function is called once per frame
* received. It notifies me that there is data to be retrieved from the driver.
* The driver's receive function is called to get the data.
*
* @param    CallBackRef is the callback reference passed from the driver, which
*           in our case is a pointer to a DriverInfo structure.
*
* @return   None.
*
* @note     This function is called by the driver within interrupt context.
*
******************************************************************************/
static void FifoRecvHandler(void *CallBackRef)
{
    XEmac *EmacPtr = (XEmac *)CallBackRef;
    Xuint32 FrameLen;
    XStatus Status;
    int Index;
    Xuint8 *FramePtr;

    /*
     * Retrieve the frame from the EMAC
     */
    FrameLen = XEM_MAX_FRAME_SIZE;
    Status = XEmac_FifoRecv(EmacPtr, (Xuint8 *)RecvBuffer, &FrameLen);
    if (Status != XST_SUCCESS)
    {
        LoopbackError = Status;
        RecvDone = XTRUE;
        return;
    }

    /*
     * Verify the frame is the correct length. SentPayloadSize is a shared
     * variable.
     */
    if (FrameLen != (SentPayloadSize + XEM_HDR_SIZE + XEM_TRL_SIZE))
    {
        LoopbackError = XST_LOOPBACK_ERROR;
        RecvDone = XTRUE;
        return;
    }

    /*
     * Verify the frame contents
     */
    FramePtr = (Xuint8 *)RecvBuffer;
    FramePtr += XEM_HDR_SIZE;    /* get past the header */
    for (Index = 0; Index < SentPayloadSize; Index++)
    {
        if (*FramePtr++ != (Xuint8)Index)
        {
            LoopbackError = XST_LOOPBACK_ERROR;
            break;
        }
    }

    RecvDone = XTRUE;
}


/*****************************************************************************/
/**
* This is the Callback function (called from driver) to handle confirmation of
* transmit events when in direct memory-mapped I/O mode.
*
* @param    CallBackRef is the callback reference passed from the driver, which
*           in our case is a pointer the driver instance.
*
* @return   None.
*
* @note     None.
*
******************************************************************************/
static void FifoSendHandler(void *CallBackRef)
{
    XEmac *EmacPtr = (XEmac *)CallBackRef;
    XEmac_Stats Stats;

    /*
     * Check stats for transmission errors (overrun or underrun errors are
     * caught by the asynchronous error handler).
     */
    XEmac_GetStats(EmacPtr, &Stats);
    if (Stats.XmitLateCollisionErrors || Stats.XmitExcessDeferral)
    {
        LoopbackError = XST_LOOPBACK_ERROR;
    }

    SendDone = XTRUE;
}

/*****************************************************************************/
/**
*
* This function is the Callback function (called from driver) to handle
* asynchronous errors. These errors are usually bad and require a reset of the
* device.  Here is an example of how to recover (albeit data will be lost during
* the reset)
*
* @param    CallBackRef is the callback reference passed from the driver, which
*           in our case is a pointer the driver instance.
* @param    Code is the Error Status
*
* @return   None.
*
* @note     None.
*
******************************************************************************/
static void ErrorHandler(void *CallBackRef, XStatus Code)
{
    XEmac *EmacPtr = (XEmac *)CallBackRef;

    LoopbackError = Code;   /* Set the shared variable */

    /*
     * Most if not all asynchronous errors returned by the XEmac driver are
     * serious.  The usual remedy is to reset the device.  The user will need
     * to re-configure the driver/device after the reset, so if you don't know
     * how it is configured, be sure to retrieve its options and configuration
     * (e.g., using the XEmac_Get... functions) before the reset.
     */
    if (Code == XST_RESET_ERROR)
    {
        /*
         * May want to set a breakpoint here during debugging
         */
        XEmac_Reset(EmacPtr);

        (void)XEmac_SetMacAddress(EmacPtr, LocalAddress);
        (void)XEmac_SetOptions(EmacPtr, DEFAULT_OPTIONS);

        (void)XEmac_Start(EmacPtr);
    }
}

/*****************************************************************************/
/**
*
* This function setups the interrupt system so interrupts can occur for the
* EMAC.  This function is application-specific since the actual system may or
* may not have an interrupt controller.  The EMAC could be directly connected
* to a processor without an interrupt controller.  The user should modify this
* function to fit the application.
*
* @param    IntcInstancePtr is the pointer to the instance of the INTC
*           component.
* @param    EmacInstancePtr is the pointer to the instance of the EMAC
*           component which is going to be connected to the interrupt
*           controller.
* @param    EmacDeviceId is the XPAR_<emac_instance>_DEVICE_ID value from
*           xparameters.h for EMAC
* @param    EmacIntrId is XPAR_<INTC_instance>_<EMAC_instance>_IP2INTC_IRPT_INTR
*           value from xparameters.h
*
* @return   XST_SUCCESS if successful, otherwise XST_FAILURE.
*
* @note     None
*
******************************************************************************/

static XStatus EmacSetupIntrSystem(XIntc *IntcInstancePtr,
                                   XEmac *EmacInstancePtr,
                                   Xuint16 EmacDeviceId,
                                   Xuint16 EmacIntrId)
{
    XStatus Status;

#ifndef TESTAPP_GEN
    /*
     * Initialize the interrupt controller driver so that it is ready to use.
     */
    Status = XIntc_Initialize(IntcInstancePtr, INTC_DEVICE_ID);
    if (Status != XST_SUCCESS)
    {
        return XST_FAILURE;
    }
#endif
    /*
     * Connect the 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(IntcInstancePtr,
                           EmacIntrId,
                           (XInterruptHandler)XEmac_IntrHandlerFifo,
                           EmacInstancePtr);
    if (Status != XST_SUCCESS)
    {
        return XST_FAILURE;
    }

#ifndef TESTAPP_GEN
    /*
     * Start the interrupt controller so interrupts are enabled for all
     * devices that cause interrupts. Specify real mode so that the EMAC
     * can cause interrupts through the interrupt controller.
     */
    Status = XIntc_Start(IntcInstancePtr, XIN_REAL_MODE);
    if (Status != XST_SUCCESS)
    {
        return XST_FAILURE;
    }
#endif
    /*
     * Enable the interrupt for the EMAC
     */
    XIntc_Enable(IntcInstancePtr, EmacIntrId);

#ifndef TESTAPP_GEN

    /*Initialize the PPC405 exception table     
    XExc_Init();

    XExc_RegisterHandler(XEXC_ID_NON_CRITICAL_INT,
                         (XExceptionHandler)XIntc_InterruptHandler,
                         IntcInstancePtr);

    XExc_mEnableExceptions(XEXC_NON_CRITICAL);

   */
 microblaze_enable_interrupts();
#endif

    return XST_SUCCESS;
}


/*****************************************************************************/
/**
*
* This function disables the interrupts that occur for the EMAC. 
*
* @param    IntrInstancePtr is the pointer to the instance of the INTC
*           component.
* @param    IntrMask is the interrupt vector for EMAC Interrupt.
*
* @return   None
*
* @note     None
*
******************************************************************************/
static void EmacDisableIntrSystem(XIntc *IntrInstancePtr, Xuint16 IntrMask)
{
   
    /*
     * Disconnect and disable the interrupt for the EMAC
     */
    XIntc_Disconnect(IntrInstancePtr, IntrMask);

}

 

 

 

Do I forget to midify something?

Message Edited by shijiluoben on 05-13-2008 07:59 PM
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