i2stest.c

来自「LPC23XX ARM的驱动程序库」· C语言 代码 · 共 73 行

/*****************************************************************************
 *   i2stest.c:  main C entry file for NXP LPC23xx/24xx Family Microprocessors
 *
 *   Copyright(C) 2006, NXP Semiconductor
 *   All rights reserved.
 *
 *   History
 *   2006.07.20  ver 1.00    Prelimnary version, first Release
 *
******************************************************************************/
#include "LPC23xx.h"                        /* LPC23xx/24xx definitions */
#include "type.h"
#include "i2s.h"

extern volatile BYTE I2STXBuffer[BUFSIZE];
extern volatile BYTE I2SRXBuffer[BUFSIZE];
extern volatile DWORD I2SReadLength;
extern volatile DWORD I2SWriteLength;
extern volatile DWORD I2SRXDone, I2STXDone;

/*******************************************************************************
**   Main Function  main()
*******************************************************************************/
int main (void)
{
    DWORD i;

	/* The test program is to connect CLK, WS, and SDA lines between the
	TX and RX. DAO is the master output, DAI is the slave input. This test
	is not a real-world application but test both TX and RX channel in
	a single program. However, due to the sync issue, the TX will start with 
	MUTE data 0 once it starts while RX is not ready. So, it may begins
	with some MUTE value in the beginning of the RX buffer. This is beyond
	control unless throw away the very first few bytes in the RX buffer. 
	In this program, the very byte is not compared between the TX buffer and
	RX buffer due to this synchonization issue. */

	/* Configure temp register before reading */
    for ( i = 0; i < BUFSIZE; i++ )	/* clear buffer */
    {
		I2STXBuffer[i] = i;
		I2SRXBuffer[i] = 0;
    }

    if ( I2SInit() == FALSE )	/* initialize I2S */
    {
		while ( 1 );			/* Fatal error */
    }

	while ( I2SWriteLength < BUFSIZE )
	{
		while (((I2S_STATE >> 16) & 0xFF) == TXFIFO_FULL);
		I2S_TX_FIFO = I2STXBuffer[I2SWriteLength++];
	}

	I2STXDone = 1;
	/* Wait for RX and TX complete before comparison */
	while ( !I2SRXDone || !I2STXDone );

	for ( i=1; i<BUFSIZE; i++ )
	{
		if ( I2SRXBuffer[i] != I2STXBuffer[i-1] )
		{
			while ( 1 );	/* Validation error */
		}
	}
    return 0;
}

/******************************************************************************
**                            End Of File
******************************************************************************/