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Hi,
I am trying to work out the SPI communication between two evaluation boards , MSP432P401R (Master) and MSP430F5529 (Slave)
the code used is directly from the examples provided by TI .
The value received is only FF . Would like to know where I am going wrong.
CODE is as follows :
1) for SPI 3-Wire Master Incremented Data (on msp432p401r)
#include "msp.h"
unsigned char RXData;
unsigned char TXData;
int main(void)
{
volatile uint32_t i;
WDTCTL = WDTPW | WDTHOLD; // Stop watchdog timer
P1SEL0 |= BIT5 | BIT6 | BIT7; // set 3-SPI pin as second function
__enable_interrupt();
NVIC_ISER0 = 1 << ((INT_EUSCIB0 - 16) & 31); // Enable eUSCIB0 interrupt in NVIC module
UCB0CTLW0 |= UCSWRST; // **Put state machine in reset**
UCB0CTLW0 |= UCMST|UCSYNC|UCCKPL|UCMSB; // 3-pin, 8-bit SPI master
// Clock polarity high, MSB
UCB0CTLW0 |= UCSSEL__ACLK; // ACLK
UCB0BR0 = 0x02; // /2,fBitClock = fBRCLK/(UCBRx+1).
UCB0BR1 = 0; //
UCB0IE |= UCRXIE;
UCB0CTLW0 &= ~UCSWRST; // **Initialize USCI state machine**
TXData = 0x01; // Holds TX data
while(1)
{
UCB0IE |= UCTXIE; // Enable TX interrupt
for (i = 2000; i > 0; i--); // Delay before next transmission
TXData++; // Increment transmit data
}
}
// SPI interrupt service routine
void eUSCIB0IsrHandler(void)
{
if (UCB0IFG & UCTXIFG)
UCB0TXBUF = TXData; // Transmit characters
UCB0IE &= ~UCTXIE;
while (!(UCB0IFG & UCRXIFG));
RXData = UCB0RXBUF;
}
2) SPI 3-Wire Slave Data Echo (msp430f5529)
#include <msp430.h>
int main(void)
{
WDTCTL = WDTPW+WDTHOLD; // Stop watchdog timer
P4SEL |= BIT4+BIT5; // P3.3,4 option select
P4SEL |= BIT0; // P2.7 option select
UCA1CTL1 |= UCSWRST; // **Put state machine in reset**
UCA1CTL0 |= UCSYNC+UCCKPL+UCMSB; // 3-pin, 8-bit SPI slave,
// Clock polarity high, MSB
UCA1CTL1 &= ~UCSWRST; // **Initialize USCI state machine**
UCA1IE |= UCRXIE; // Enable USCI_A1 RX interrupt
__enable_interrupt();
}
#pragma vector=USCI_A1_VECTOR
__interrupt void USCI_A1_ISR(void)
{
if (UCA1IFG & UCRXIFG)
while (!(UCA1IFG & UCTXIFG));
UCA1TXBUF = UCA1RXBUF;
}
Thanks
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