Posted on May 17, 2011 at 12:09Hi,
I am trying to interface uPSD3334D Controller and SPI ADC Chip(TLC3578 from TI). I am able to communicate with ADC at less than 2.5MHz speed. When I increase the speed, from first byte and second byte a delay of more than 30uSec is coming.
I am using the code I received with ST development kit as reference. Please help. I am attaching the modified code.
Thanks.
Jose
void SPI_Init(void)
{
P4SFS0 = 0xF0;
P4SFS1 = 0xF0;
SPICON1=0x00;
SPICLKD=0x04; SPICON0=0x18;
IEA|=0x40;
IPA|=0x40;
EA=1;
}
void spiRead()
{
SPI_transfer(&INITIALIZE,0,2); //0xA0,0X00
SPI_transfer(&CONFIGURE,0,2); //0XAE, 0X42
SPI_transfer(&READ_FIFO,&RDFF_RX,16); //0XE0,0X00
}
void SPI_transfer(unsigned char *send, unsigned char *receive, unsigned char length)
{
tlength = length;
buf1 = send;
buf2 = receive;
flag1 = *buf1;
flag = 0;
endflag = 0;
while (SPISTAT & SPI_BUSY_FLAG);
SPITDR = *buf1;
buf1++;
tlen = 1;
rlen = 0;
SPICON1 |= RIE;
SPICON1 |= RORIE;
SPICON1 |= TEIE;
SPICON1 |= TIE;
SPICON0 |= TE;
SPICON0 |= RE;
}
void SPI_isr (void) interrupt SPI_VECTOR using 2
{
unsigned char status ;
status = SPISTAT;
if(status & SPI_TRANSMIT_END_FLAG)
{
while (SPISTAT & SPI_BUSY_FLAG);
SPICON1 &= (~TIE);
SPICON0 &= (~TE);
SPICON1 &= (~TEIE);
endflag = 1;
}
if(status & SPI_TI_FLAG)
{
if(tlen < tlength)
{
SPITDR = *buf1;
buf1++;
tlen++;
}
}
if(status & SPI_RI_FLAG)
{
*buf2=SPIRDR;
buf2++;
rlen++;
}
} return 0;
}
