Hi, I`ve a problem with SPI on 2809. I`ve tried the examples with loopback and with the code written by myself. Actually I have no clue what is wrong, when I set to 16-bit character length there is a transmission on miso/mosi seen on osciloscope, but when I change from 16 to 8 bit char length mosi line is dead.
here is the init spi:
void InitSpi(void){
SpibRegs.SPICCR.bit.SPISWRESET = 0; // Reset SPI
SpibRegs.SPIFFTX.all = 0xE040;
SpibRegs.SPIFFRX.all = 0x204F;
SpibRegs.SPIFFCT.all = 0x0;
SpibRegs.SPIFFTX.bit.SPIFFENA = 0; // Enable FIFO's
SpibRegs.SPICTL.all = 0x0006; // Master, Talk enabled
SpibRegs.SPISTS.all = 0x0000;
SpibRegs.SPIBRR = 127; // Baud rate - najwolniejszy
SpibRegs.SPIPRI.bit.FREE = 1; // Set so breakpoints don't disturb xmission
SpibRegs.SPICCR.all = 0x009F; // Relinquish SPI from Reset, 0 0 |1001| 1111 -> |reset,loop on|
}
some defs:
#define WREN 0x06 /* set write enable latch for NM25C020 */
#define WRDI 0x04 /* reset write enable latch */
#define RDSR 0x05 /* read status register */
#define WRSR 0x01 /* write status register */
#define READ 0x03 /* read data from memory */
#define WRITE 0x02 /* write dato to memory */
#define DUMMY 0x00;
and the example func which I use to test te transmission:
Uint16 ReadStatusEEPROM(void){
Uint16 stat;
/* reads status register out of the EEPROM */
SpibRegs.SPITXBUF = RDSR; // write opcode into serial shift data register
while(SpibRegs.SPISTS.bit.INT_FLAG == 0){}
DELAY_US(100);
SpibRegs.SPITXBUF = DUMMY; // write dummy into serial shift data register
while(SpibRegs.SPISTS.bit.INT_FLAG == 0){}
stat = SpibRegs.SPIRXBUF; // receive status of the EEPROM
while(SpibRegs.SPISTS.bit.INT_FLAG == 0){}
return(stat);
}
In future I will use spi for communication with eeprom 25lc160 and as I can see I need 8bit communication, because it will be much simplier form me.
