用MSP430G2553调试nrf24l0时，因为应经用USCI_A0作为uart ,想用USCI_B0作为SPI与nrf24l10通信，却不成功，求解！！！！

user3506972

Prodigy 20 points

如果用USCI_A0作为SPI就可以跟NRF24L01通信，换成USCI_B0就不行，why???

//这是对NRF24L01写读

uchar SPI_RW(uchar byte)

{

while(!(IFG2 & UCB0TXIFG));
UCB0TXBUF=byte;
//Delay_us(20);
while(!(IFG2 & UCB0RXIFG));
return(UCB0RXBUF);
}

// uart 和spi 初始化

void UART_init(void)
{
DCOCTL = 0x00;
BCSCTL1 = CALBC1_1MHZ;
DCOCTL = CALDCO_1MHZ;

UCA0CTL1 |= UCSWRST;
UCB0CTL1 |= UCSWRST;

P1SEL = BIT1 + BIT2 ;
P1SEL2 = BIT1 + BIT2 ;
UCA0CTL1 |= UCSSEL_2;
UCA0BR0 = 104;
UCA0BR1 = 0;
UCA0MCTL = 0;

UCB0CTL0 |= UCCKPH+ UCMSB + UCMST + UCSYNC ; // 3-pin, 8-bit SPI master
UCB0CTL1 |= UCSSEL_2; // SMCLK
UCB0BR0 |= 0x08; // /2
UCB0BR1 = 0;

UCA0CTL1 &= ~UCSWRST;
UCB0CTL1 &= ~UCSWRST;

}

12 年多前

0 Peter_Zheng 12 年多前

TI__Expert 8395 points

void SPI_Init(void)
{
UCB0CTL0 = UCMSB + UCMST + UCMODE_1 + UCSYNC; // MSB First; Set TBA as master; 4Pin Mode, slave active on UCB1STE=>NCS low; SPI Mode
UCB0CTL1 = UCSWRST + UCSSEL_2; // Reset and hold reset logic state; SMCLK as USC clock source
UCB0BR0 = 0x50; // Set Baud Rate divider (MSByte) for SPI clock
UCB0BR1 = 0; // Set Baud Rate divider (LSByte) for SPI clock

P1SEL |= BIT5 + BIT6 + BIT7; // Configure P1.5, P1.6, & P1.7 as SPICLK, SOMI, and SIMO to talk to BAST
P1SEL2|= BIT5 + BIT6 + BIT7;

P1DIR |= BIT5 + BIT6 + BIT7; // SPICLK, SOMI, and SIMO as outputs

P1DIR &= ~BIT6; // SOMI as input
P1DIR &= ~BIT3; // INT as input

UCB0CTL1 &= ~UCSWRST; // Leave logic reset state. Starts SPI state machine
}

void UART_Init(void)
{
P1SEL = BIT1 + BIT2 ; // P1.1 = RXD, P1.2=TXD
P1SEL2 = BIT1 + BIT2 ;
UCA0CTL1 |= UCSSEL_2; // SMCLK
UCA0BR0 = 0x41; // 8MHz 9600 Baud Rate
UCA0BR1 = 0x03; // 8MHz 9600 Baud Rate
UCA0MCTL = UCBRS0; // Modulation UCBRSx = 1
UCA0CTL1 &= ~UCSWRST; // **Initialize USCI state machine**
IE2 |= UCA0RXIE; // Enable USCI_A0 RX interrupt
}

两个配置，实际应用的代码，做参考。