头文件、宏定义 //########################################################################### #include 'DSP28x_Project.h' // Device Headerfile and Examples Include File#include 'Example_posspeed.h' // Example specific Include file#include
增量式PID函数 struct _pid{ float setspeed; float actualspeed; float err; float err_last; float err_last2; float kp,ki,kd; }pid; void pid_init(){ pid.setspeed=0; pid.actualspeed=0; pid.err=0.0; pid.err_last=0.0; pid.err_last2=0.0; pid.kp=0.5; pid.ki=0.3; pid.kd=0.15; } void pid_realize()//增量式 { pid.setspeed=150; pid.actualspeed=V; pid.err=pid.setspeed-pid.actualspeed; float incrementspeed=pid.kp*(pid.err-pid.err_last)+pid.ki*pid.err+pid.kd*(pid.err-2*pid.err_last+pid.err_last2);//增量速度 pid.err_last2=pid.err_last; pid.err_last=pid.err; N=N-(incrementspeed/200);//占空比系数(占空比=SP*N) if(N>0.5) N=0.5; else if (N<0) N=0; else N=N; } //没有考虑死区，没有设定上下限
GPIO配置函数void configtestled(void){ EALLOW; GpioCtrlRegs.GPBMUX2.bit.GPIO54 = 0; // GPIO6复用为GPIO功能 GpioCtrlRegs.GPBDIR.bit.GPIO54 = 1; // GPIO6设置为输出 GpioCtrlRegs.GPBMUX2.bit.GPIO55 = 0; // GpioCtrlRegs.GPBDIR.bit.GPIO55 = 1; GpioCtrlRegs.GPBMUX2.bit.GPIO56 = 0; // GPIO6复用为GPIO功能 GpioCtrlRegs.GPBDIR.bit.GPIO56 = 1; // GPIO6设置为输出 GpioCtrlRegs.GPBMUX2.bit.GPIO57 = 0; // GpioCtrlRegs.GPBDIR.bit.GPIO57 = 1; EDIS;}
主函数void main(void){// char *msg; N=1.0; V=0;// Uint16 ReceivedChar;// Step 1. Initialize System Control:// PLL, WatchDog, enable Peripheral Clocks// This example function is found in the DSP2833x_SysCtrl.c file. InitSysCtrl();// Step 2. Initalize GPIO:// This example function is found in the DSP2833x_Gpio.c file and// illustrates how to set the GPIO to it's default state.// InitGpio(); // Skipped for this example InitEQep1Gpio(); InitEPwm2Gpio(); InitEPwm4Gpio(); InitScibGpio(); EALLOW; GpioCtrlRegs.GPADIR.bit.GPIO4 = 1; // GPIO4 as output simulates Index signal GpioDataRegs.GPACLEAR.bit.GPIO4 = 1; // Normally low EDIS;// Step 3. Clear all interrupts and initialize PIE vector table:// Disable CPU interrupts DINT; // Initialize the PIE control registers to their default state.// The default state is all PIE interrupts disabled and flags// are cleared.// This function is found in the DSP2833x_PieCtrl.c file. InitPieCtrl(); // Disable CPU interrupts and clear all CPU interrupt flags: IER = 0x0000; IFR = 0x0000; // Initialize the PIE vector table with pointers to the shell Interrupt// Service Routines (ISR).// This will populate the entire table, even if the interrupt// is not used in this example. This is useful for debug purposes.// The shell ISR routines are found in DSP2833x_DefaultIsr.c.// This function is found in DSP2833x_PieVect.c. InitPieVectTable(); // Interrupts that are used in this example are re-mapped to// ISR functions found within this file. EALLOW; // This is needed to write to EALLOW protected registers PieVectTable.EPWM1_INT= &prdTick;//确定中断服务程序的入口地址 EDIS; // This is needed to disable write to EALLOW protected registers pid_init(); EPwmSetup(); // This function exists in Example_EPwmSetup.c// Step 5. User specific code, enable interrupts:// Enable CPU INT1 which is connected to CPU-Timer 0: IER |= M_INT3; // Enable TINT0 in the PIE: Group 3 interrupt 1 PieCtrlRegs.PIEIER3.bit.INTx1 = 1;//使能第三组中断的第一个小中断 // Enable global Interrupts and higher priority real-time debug events: EINT; // Enable Global interrupt INTM ERTM; // Enable Global realtime interrupt DBGM //LoopCount=0; //ErrorCount=0; scib_fifo_init(); // Initialize the SCI FIFO scib_echoback_init(); // Initalize SCI for echoback // msg='\r\n\n\nStart the velocity measurement!\n\0';// scib_msg(msg); configtestled(); // LED1=1; // DELAY_US(50000); // LED2=0; // DELAY_US(50000000); // LED1=0; // DELAY_US(50000); // LED2=1; // DELAY_US(5000000); // LED1=0; // LED2=0; // DELAY_US(50000); LED3=1; DELAY_US(50000); LED4=0; DELAY_US(50000); // LED3=0; // DELAY_US(50000); // LED4=1; // DELAY_US(50000000); // LED3=0; // LED4=0; qep_posspeed.init(&qep_posspeed); while (1) { //int32 i=0; // while(i<320000) // { pid_realize(); //PID调节 M=7500*N; EPwm2Regs.CMPA.half.CMPA=M; //占空比更新 EQep1Regs.QFLG.bit.UTO==1; //高速测量中断产生 qep_posspeed.calc(&qep_posspeed); // i++; // } scib_xmit(V); //串口显示 } }
测速中断函数 interrupt void prdTick(void) // EPWM1 Interrupts once every 4 QCLK counts (one period){ Uint16 i; // Position and Speed measurement qep_posspeed.calc(&qep_posspeed); // Control loop code for position control & Speed contol Interrupt_Count++; if (Interrupt_Count==2500) // Every 1000 interrupts(4000 QCLK counts or 1 rev.) { EALLOW; GpioDataRegs.GPASET.bit.GPIO4 = 1; // Pulse Index signal (1 pulse/rev.) for (i=0; i<700; i++){ } GpioDataRegs.GPACLEAR.bit.GPIO4 = 1; Interrupt_Count = 0; // Reset count EDIS; } // Acknowledge this interrupt to receive more interrupts from group 1 PieCtrlRegs.PIEACK.all = PIEACK_GROUP3; EPwm1Regs.ETCLR.bit.INT=1; }
串口发送函数、引脚配置函数void scib_echoback_init(){ // Note: Clocks were turned on to the SCIA peripheral // in the InitSysCtrl() function ScibRegs.SCICCR.all =0x0007; // 1 stop bit, No loopback // No parity,8 char bits, // async mode, idle-line protocol ScibRegs.SCICTL1.all =0x0003; // enable TX, RX, internal SCICLK, // Disable RX ERR, SLEEP, TXWAKE ScibRegs.SCICTL2.all =0x0003; ScibRegs.SCICTL2.bit.TXINTENA = 1; ScibRegs.SCICTL2.bit.RXBKINTENA =1; ScibRegs.SCIHBAUD =0x0001; // 9600 baud @LSPCLK = 37.5MHz. ScibRegs.SCILBAUD =0x00E7; ScibRegs.SCICTL1.all =0x0023; // Relinquish SCI from Reset} // Transmit a character from the SCIvoid scib_xmit(int a){ while (ScibRegs.SCICTL2.bit.TXRDY == 0) {} ScibRegs.SCITXBUF=a; } void scib_msg(char * msg){ int i; i = 0; while(msg[i] != '\0') { scib_xmit(msg[i]); i++; }} // Initalize the SCI FIFOvoid scib_fifo_init(){ ScibRegs.SCIFFTX.all=0x8000; }void InitScibGpio(){ EALLOW; GpioCtrlRegs.GPAPUD.bit.GPIO18 = 0; // Enable pull-up for GPIO18 (SCITXDB) GpioCtrlRegs.GPAPUD.bit.GPIO19 = 0; // Enable pull-up for GPIO19 (SCIRXDB) GpioCtrlRegs.GPAQSEL2.bit.GPIO18 = 3; GpioCtrlRegs.GPAQSEL2.bit.GPIO19 = 3; // Asynch input GPIO19 (SCIRXDB) GpioCtrlRegs.GPAMUX2.bit.GPIO18 = 2; // Configure GPIO18 for SCITXDB operation GpioCtrlRegs.GPAMUX2.bit.GPIO19 = 2; // Configure GPIO19 for SCIRXDB operation EDIS;}
要结合官方例程看，或结合书籍《手把手教你学DSP---基于TMS320F28335》