说明:传感器工作在SPI的模式0,传输速度最高10MHZ,MSB,8bit数据;
程序概括:使用芯片的SPIB引脚,根据官方例程进行代码修改,完成寄存器配置
目前程序现象:已关闭自循环标志位,但是发送数据以后,还是会在接收寄存器观察到相同的数据,就是发什么接受什么。
代码:
1、主程序
#include "F28x_Project.h" void spi_xmit(Uint16 a); void spi_fifo_init(void); void spib_fifo_init(void); unsigned char spib_xmit(unsigned char a); unsigned char RecData; unsigned char SendData; void main(void) { InitSysCtrl(); InitSpibGpio(); DINT; InitPieCtrl(); IER = 0x0000; IFR = 0x0000; InitPieVectTable(); spib_fifo_init(); // Initialize the SPI FIFO SendData = 0x00; for(;;) { RecData = spib_xmit(SendData); SendData++; if(SendData == 0xFF) { SendData = 0x00; } } } // // spi_fifo_init - Initialize SPIB FIFO // void spib_fifo_init(void) { // // Initialize SPI FIFO registers // SpibRegs.SPIFFTX.all = 0xE040; SpibRegs.SPIFFRX.all = 0x2044; SpibRegs.SPIFFCT.all = 0x0; // // Initialize core SPI registers // InitSpib(); } // // spi_xmit - Transmit value via SPI // unsigned char spib_xmit(unsigned char a) { unsigned char Receive; SpibRegs.SPITXBUF = a; while(SpibRegs.SPIFFRX.bit.RXFFST !=1) { } Receive = SpibRegs.SPIRXBUF; Receive = Receive >> 8; return Receive; } // // End of file //
2、SPIB的引脚和寄存器配置
void InitSpib(void) { // Initialize SPI-B // Set reset low before configuration changes // Clock polarity (0 == rising, 1 == falling) // 8-bit character // Disable loop-back SpibRegs.***.bit.SPISWRESET = 0; SpibRegs.***.bit.CLKPOLARITY = 0; SpibRegs.***.bit.*** = (8-1); SpibRegs.***.bit.SPILBK = 0; // Enable master (0 == slave, 1 == master) // Enable transmission (Talk) // Clock phase (0 == normal, 1 == delayed) // SPI interrupts are disabled SpibRegs.***.bit.MASTER_SLAVE = 1; SpibRegs.***.bit.TALK = 1; SpibRegs.***.bit.CLK_PHASE = 0; SpibRegs.***.bit.SPIINTENA = 0; // Set the baud rate SpibRegs.SPIBRR.bit.SPI_BIT_RATE = SPI_BRR; // Set FREE bit // Halting on a breakpoint will not halt the SPI SpibRegs.SPIPRI.bit.FREE = 1; // Release the SPI from reset SpibRegs.***.bit.SPISWRESET = 1; } void InitSpibGpio(void) { EALLOW; GpioCtrlRegs.GPAPUD.bit.GPIO24 = 0; // Enable pull-up on GPIO16 (SPISIMOB) GpioCtrlRegs.GPAPUD.bit.GPIO25 = 0; // Enable pull-up on GPIO17 (SPISOMIB) GpioCtrlRegs.GPAPUD.bit.GPIO26 = 0; // Enable pull-up on GPIO18 (***) GpioCtrlRegs.GPAPUD.bit.GPIO27 = 0; // Enable pull-up on GPIO19 (SPISTEB) GpioCtrlRegs.GPAQSEL2.bit.GPIO24 = 3; // Asynch input GPIO16 (SPISIMOB) GpioCtrlRegs.GPAQSEL2.bit.GPIO25 = 3; // Asynch input GPIO17 (SPISOMIB) GpioCtrlRegs.GPAQSEL2.bit.GPIO26 = 3; // Asynch input GPIO18 (***) GpioCtrlRegs.GPAQSEL2.bit.GPIO27 = 3; // Asynch input GPIO19 (SPISTEB) GpioCtrlRegs.GPAGMUX2.bit.GPIO24 = 1; // Configure GPIO16 as SPISIMOA GpioCtrlRegs.GPAGMUX2.bit.GPIO25 = 1; // Configure GPIO17 as SPISOMIA GpioCtrlRegs.GPAGMUX2.bit.GPIO26 = 1; // Configure GPIO18 as *** GpioCtrlRegs.GPAGMUX2.bit.GPIO27 = 1; // Configure GPIO19 as SPISTEA GpioCtrlRegs.GPAMUX2.bit.GPIO24 = 2; // Configure GPIO16 as SPISIMOA GpioCtrlRegs.GPAMUX2.bit.GPIO25 = 2; // Configure GPIO17 as SPISOMIA GpioCtrlRegs.GPAMUX2.bit.GPIO26 = 2; // Configure GPIO18 as *** GpioCtrlRegs.GPAMUX2.bit.GPIO27 = 2; // Configure GPIO19 as SPISTEA EDIS; }