hi all,
M new bie in I2C and m using MSP430F53xx series of controller for controlling and updating registers of PCM9211 using I2C, for this i picked up a example code of CCS 5.2 for sending multiple byte to slave but its not working and I'm unable to recognize whats wrong going here, so i tried I2C between two MSP430 and again its not working...
both hardware were individually working fine during I2C in my scope SCL or SDA is always High.
m attaching my code, please have a look
only modification in example code MSP430F530x_uscib0_i2c_08 is TxData sending
in my code P3.0 n P3.1 is configured as SDA, SCL line, 10k external pullup is also used.
through this code i have to update various registers of PCM9211, so first byte of tx data is reg addr. and then reg. value and so on.
m pasting code here...
//******************************************************************************
// MSP430F530x Demo - USCI_B0 I2C Master TX multiple bytes to PCM9211 Slave
//
// Description: This demo connects MSP430's via the I2C bus. The master
// transmits to the slave. This is the MASTER CODE. It cntinuously
// transmits an array of data and demonstrates how to implement an I2C
// master transmitter sending multiple bytes using the USCI_B0 TX interrupt.
// ACLK = n/a, MCLK = SMCLK = BRCLK = default DCO = ~1.045MHz */
#include <msp430.h>
unsigned char *PTxData; // Pointer to TX data
unsigned char TXByteCtr;
const unsigned char TxData[ ] = // Table of data to transmit, reg loc. then value
{
0x40,0x33,
0x40,0xc0,
0x31,0x1A,
0x33,0x22,
0x20,0x00,
0x24,0x00,
0x26,0x81,
0x33,0x22,
0x42,0x02,
0X48,0X00,
0x49,0x00,
0x46,0xD7,
0x47,0xD7,
0x60,0x22,
0x61,0x10,
0x62,0x00,
0x78,0xDD,
0x6E,0x0F,
0x6F,0x40,
0x6B,0x22
};
int main(void)
{
unsigned int i;
WDTCTL = WDTPW | WDTHOLD; // Stop WDT
P3SEL |= 0x03; // Assign I2C pins to USCI_B0
UCB0CTL1 |= UCSWRST; // Enable SW reset
UCB0CTL0 = UCMST | UCMODE_3 | UCSYNC; // I2C Master, synchronous mode
UCB0CTL1 = UCSSEL_2 | UCSWRST; // Use SMCLK, keep SW reset
UCB0BR0 = 12; // fSCL = SMCLK/12 = ~100kHz
UCB0BR1 = 0;
UCB0I2CSA = 0x80; // Slave Address is 048h
UCB0CTL1 &= ~UCSWRST; // Clear SW reset, resume operation
UCB0IE |= UCTXIE; // Enable TX interrupt
while (1)
{
for(i=0;i<10;i++); // Delay required between transaction
PTxData = (unsigned char *)TxData; // TX array start address
// transmit operation.
TXByteCtr = sizeof TxData; // Load TX byte counter
UCB0CTL1 |= UCTR | UCTXSTT; // I2C TX, start condition
__bis_SR_register(LPM0_bits | GIE); // Enter LPM0, enable interrupts
__no_operation(); // Remain in LPM0 until all data
// is TX'd
while (UCB0CTL1 & UCTXSTP); // Ensure stop condition got sent
}
}
#pragma vector = USCI_B0_VECTOR
__interrupt void USCI_B0_ISR(void)
{
switch(__even_in_range(UCB0IV,12))
{
case 0: break; // Vector 0: No interrupts
case 2: break; // Vector 2: ALIFG
case 4: break; // Vector 4: NACKIFG
case 6: break; // Vector 6: STTIFG
case 8: break; // Vector 8: STPIFG
case 10: break; // Vector 10: RXIFG
case 12: // Vector 12: TXIFG
if (TXByteCtr) // Check TX byte counter
{
UCB0TXBUF = *PTxData++; // Load TX buffer
TXByteCtr--; // Decrement TX byte counter
}
else
{
UCB0CTL1 |= UCTXSTP; // I2C stop condition
UCB0IFG &= ~UCTXIFG; // Clear USCI_B0 TX int flag
__bic_SR_register_on_exit(LPM0_bits); // Exit LPM0
}
default: break;
}
}
please assist as soon as possible whats wrong
I have few more queries
1.how to check ACK n NACK signal using this code, because it may explains device is selected or i can check for successfully tx of last data then new data s transmitted
2. or may i blink an led during proper communication
please reply as soon as possible and looking for your valuable replies
regards:-
Sonu Verma