serial.c

来自「JENNIC无线传感器网络 ZIGBEE 文件资料」· C语言 代码 · 共 241 行

/****************************************************************************
 *
 * MODULE:             Serial
 *
 * COMPONENT:          serial.c,v
 *
 * VERSION:            AT-Jenie_Release_v1_RC3
 *
 * REVISION:           1.3
 *
 * DATED:              2007/09/25 09:03:20
 *
 * STATUS:             Exp
 *
 * AUTHOR:             MRW
 *
 * DESCRIPTION:        Generic buffered UART serial communications with RX
 *                     flow control on RTS
 *
 * CHANGE HISTORY:
 *
 * serial.c,v
 *
 *
 * MRW
 *
 * LAST MODIFIED BY:   mwild
 *                     $Modtime: $
 *
 ****************************************************************************
 *
 *  (c) Copyright 2007 JENNIC Ltd
 *
 ****************************************************************************/

/****************************************************************************/
/***        Include files                                                 ***/
/****************************************************************************/

#include <jendefs.h>
#include <AppHardwareApi.h>

#include "interrupt.h"
#include "uart.h"
#include "queue.h"
#include "serial.h"

/****************************************************************************/
/***        Macro Definitions                                             ***/
/****************************************************************************/

#define SERIAL_TX_QUEUE_SIZE                32
#define SERIAL_RX_QUEUE_SIZE                32
#define SERIAL_RX_QUEUE_HIGH_WATER_MARK     28
#define SERIAL_RX_QUEUE_LOW_WATER_MARK      4

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

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

PRIVATE void vRxChar(uint8 u8Char);
PRIVATE void vTxReady(void);

/****************************************************************************/
/***        Exported Variables                                            ***/
/****************************************************************************/

/****************************************************************************/
/***        Local Variables                                               ***/
/****************************************************************************/

QUEUE_DECLARE_Q(sRxQueue, SERIAL_RX_QUEUE_SIZE); /* [I SP001222_P1 282]*/
QUEUE_DECLARE_Q(sTxQueue, SERIAL_TX_QUEUE_SIZE); /* [I SP001222_P1 282]*/

/****************************************************************************/
/***        Exported Functions                                            ***/
/****************************************************************************/

/****************************************************************************/
/***        Local Functions                                               ***/
/****************************************************************************/

/****************************************************************************
 *
 * NAME: vSerial_Init
 *
 * DESCRIPTION:
 *
 * PARAMETERS:      Name            RW  Usage
 * None.
 *
 * RETURNS:
 * None.
 *
 * NOTES:
 * None.
 ****************************************************************************/

PUBLIC void vSerial_Init(void)
{
    vUART_Init(vRxChar, vTxReady);
    vUART_RtsStartFlow(); /* [I SP001222_P1 284]*/
}

/****************************************************************************
 *
 * NAME: vSerial_TxChar
 *
 * DESCRIPTION:
 *
 * PARAMETERS:      Name            RW  Usage
 * None.
 *
 * RETURNS:
 * None.
 *
 * NOTES:
 * None.
 ****************************************************************************/

PUBLIC bool_t bSerial_TxChar(uint8 u8Chr)
{
    bool_t bStatus = TRUE;

    /*
     * prevent race condition where transmitter is busy, but becomes ready
     * between reading its status and queuing the character to transmit
     */
    vInterrupt_Suspend();

    if (bQueue_Empty(sTxQueue) && bUART_TxReady()) {
        vUART_SetTxInterrupt(TRUE);
        vUART_TxChar(u8Chr);
    } else {
        if (!bQueue_Full(sTxQueue)) {
            vQueue_AddItem(sTxQueue, u8Chr);
        } else {
            bStatus = FALSE;
        }
    }

    vInterrupt_Resume();

    return bStatus;
}

/****************************************************************************
 *
 * NAME: i16Serial_RxChar
 *
 * DESCRIPTION:
 *
 * PARAMETERS:      Name            RW  Usage
 * None.
 *
 * RETURNS:
 * None.
 *
 * NOTES:
 * None.
 ****************************************************************************/

PUBLIC int16 i16Serial_RxChar(void)
{
    int16 i16Result = -1;

    if(!bQueue_Empty(sRxQueue)) {
        i16Result = (int16)u8Queue_RemoveItem(sRxQueue);

        if (u16Queue_Count(sRxQueue) == SERIAL_RX_QUEUE_LOW_WATER_MARK) {
            vUART_RtsStartFlow(); /* [I SP001222_P1 286]*/
        }
    }

    return i16Result;
}

/****************************************************************************/
/***        Local Functions                                               ***/
/****************************************************************************/

/****************************************************************************
 *
 * NAME: vTxReady
 *
 * DESCRIPTION:
 * Transmitter ready callback
 *
 * PARAMETERS:      Name            RW  Usage
 * None.
 *
 * RETURNS:
 * None.
 *
 * NOTES:
 * None.
 ****************************************************************************/

PRIVATE void vTxReady(void)
{
    if (!bQueue_Empty(sTxQueue)) {
        vUART_TxChar(u8Queue_RemoveItem(sTxQueue));
    } else {
        vUART_SetTxInterrupt(FALSE);
    }
}

/****************************************************************************
 *
 * NAME: vRxChar
 *
 * DESCRIPTION:
 * Receive character callback
 *
 * PARAMETERS:      Name            RW  Usage
 * None.
 *
 * RETURNS:
 * None.
 *
 * NOTES:
 * None.
 ****************************************************************************/

PRIVATE void vRxChar(uint8 u8Char)
{
    vQueue_AddItem(sRxQueue, u8Char);

    if (u16Queue_Count(sRxQueue) == SERIAL_RX_QUEUE_HIGH_WATER_MARK) {
        vUART_RtsStopFlow(); /* [I SP001222_P1 285]*/
    }
}

/****************************************************************************/
/***        END OF FILE                                                   ***/
/****************************************************************************/