// TI File $Revision: /main/1 $
// Checkin $Date: September 19, 2008 16:34:55 $
//###########################################################################
//
// FILE: Example_2802xEPwmUpDownAQ.c
//
// TITLE: Action Qualifier Module - Using up/down count
//
// ASSUMPTIONS:
//
// This program requires the DSP2802x header files.
//
// Monitor ePWM1-ePWM3 pins on an oscilloscope as described
// below.
//
// EPWM1A is on GPIO0
// EPWM1B is on GPIO1
//
// EPWM2A is on GPIO2
// EPWM2B is on GPIO3
//
// EPWM3A is on GPIO4
// EPWM3B is on GPIO5
//
// As supplied, this project is configured for "boot to SARAM"
// operation. The 2802x Boot Mode table is shown below.
// For information on configuring the boot mode of an eZdsp,
// please refer to the documentation included with the eZdsp,
//
// $Boot_Table
// While an emulator is connected to your device, the TRSTn pin = 1,
// which sets the device into EMU_BOOT boot mode. In this mode, the
// peripheral boot modes are as follows:
//
// Boot Mode: EMU_KEY EMU_BMODE
// (0xD00) (0xD01)
// ---------------------------------------
// Wait !=0x55AA X
// I/O 0x55AA 0x0000
// SCI 0x55AA 0x0001
// Wait 0x55AA 0x0002
// Get_Mode 0x55AA 0x0003
// SPI 0x55AA 0x0004
// I2C 0x55AA 0x0005
// OTP 0x55AA 0x0006
// Wait 0x55AA 0x0007
// Wait 0x55AA 0x0008
// SARAM 0x55AA 0x000A <-- "Boot to SARAM"
// Flash 0x55AA 0x000B
// Wait 0x55AA Other
//
// Write EMU_KEY to 0xD00 and EMU_BMODE to 0xD01 via the debugger
// according to the Boot Mode Table above. Build/Load project,
// Reset the device, and Run example
//
// $End_Boot_Table
//
//
// DESCRIPTION:
//
// This example configures ePWM1, ePWM2, ePWM3 to produce an
// waveform with independant modulation on EPWMxA and
// EPWMxB.
//
// The compare values CMPA and CMPB are modified within the ePWM's ISR
//
// The TB counter is in up/down count mode for this example.
//
// View the EPWM1A/B, EPWM2A/B and EPWM3A/B waveforms
// via an oscilloscope
//
//
//###########################################################################
// $TI Release: 2802x Header Files V1.00 $
// $Release Date: November 10, 2008 $
//###########################################################################
#include "DSP28x_Project.h" // Device Headerfile and Examples Include File
typedef struct
{
volatile struct EPWM_REGS *EPwmRegHandle;
Uint16 EPwm_CMPA_Direction;
Uint16 EPwm_CMPB_Direction;
Uint16 EPwmTimerIntCount;
Uint16 EPwmMaxCMPA;
Uint16 EPwmMinCMPA;
Uint16 EPwmMaxCMPB;
Uint16 EPwmMinCMPB;
}EPWM_INFO;
// Prototype statements for functions found within this file.
void InitEPwm1Example(void);
void InitEPwm2Example(void);
void InitEPwm3Example(void);
interrupt void epwm1_isr(void);
interrupt void epwm2_isr(void);
interrupt void epwm3_isr(void);
void update_compare(EPWM_INFO*);
// Global variables used in this example
EPWM_INFO epwm1_info;
EPWM_INFO epwm2_info;
EPWM_INFO epwm3_info;
// Configure the period for each timer
#define EPWM1_TIMER_TBPRD 2000 // Period register
#define EPWM1_MAX_CMPA 1950
#define EPWM1_MIN_CMPA 50
#define EPWM1_MAX_CMPB 1950
#define EPWM1_MIN_CMPB 50
#define EPWM2_TIMER_TBPRD 2000 // Period register
#define EPWM2_MAX_CMPA 1950
#define EPWM2_MIN_CMPA 50
#define EPWM2_MAX_CMPB 1950
#define EPWM2_MIN_CMPB 50
#define EPWM3_TIMER_TBPRD 2000 // Period register
#define EPWM3_MAX_CMPA 950
#define EPWM3_MIN_CMPA 50
#define EPWM3_MAX_CMPB 1950
#define EPWM3_MIN_CMPB 1050
// To keep track of which way the compare value is moving
#define EPWM_CMP_UP 1
#define EPWM_CMP_DOWN 0
void main(void)
{
// Step 1. Initialize System Control:
// PLL, WatchDog, enable Peripheral Clocks
// This example function is found in the DSP2802x_SysCtrl.c file.
InitSysCtrl();
// Step 2. Initalize GPIO:
// This example function is found in the DSP2802x_Gpio.c file and
// illustrates how to set the GPIO to it's default state.
// InitGpio(); // Skipped for this example
// For this case just init GPIO pins for ePWM1, ePWM2, ePWM3
// These functions are in the DSP2802x_EPwm.c file
InitEPwm1Gpio();
InitEPwm2Gpio();
InitEPwm3Gpio();
// 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 DSP2802x_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 DSP2802x_DefaultIsr.c.
// This function is found in DSP2802x_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 = &epwm1_isr;
PieVectTable.EPWM2_INT = &epwm2_isr;
PieVectTable.EPWM3_INT = &epwm3_isr;
EDIS; // This is needed to disable write to EALLOW protected registers
// Step 4. Initialize all the Device Peripherals:
// This function is found in DSP2802x_InitPeripherals.c
// InitPeripherals(); // Not required for this example
// For this example, only initialize the ePWM
EALLOW;
SysCtrlRegs.PCLKCR0.bit.TBCLKSYNC = 0;
EDIS;
InitEPwm1Example();
InitEPwm2Example();
InitEPwm3Example();
EALLOW;
SysCtrlRegs.PCLKCR0.bit.TBCLKSYNC = 1;
EDIS;
// Step 5. User specific code, enable interrupts:
// Enable CPU INT3 which is connected to EPWM1-3 INT:
IER |= M_INT3;
// Enable EPWM INTn in the PIE: Group 3 interrupt 1-3
PieCtrlRegs.PIEIER3.bit.INTx1 = 1;
PieCtrlRegs.PIEIER3.bit.INTx2 = 1;
PieCtrlRegs.PIEIER3.bit.INTx3 = 1;
// Enable global Interrupts and higher priority real-time debug events:
EINT; // Enable Global interrupt INTM
ERTM; // Enable Global realtime interrupt DBGM
// Step 6. IDLE loop. Just sit and loop forever (optional):
for(;;)
{
asm(" NOP");
}
}
interrupt void epwm1_isr(void)
{
// Update the CMPA and CMPB values
update_compare(&epwm1_info);
// Clear INT flag for this timer
EPwm1Regs.ETCLR.bit.INT = 1;
// Acknowledge this interrupt to receive more interrupts from group 3
PieCtrlRegs.PIEACK.all = PIEACK_GROUP3;
}
interrupt void epwm2_isr(void)
{
// Update the CMPA and CMPB values
update_compare(&epwm2_info);
// Clear INT flag for this timer
EPwm2Regs.ETCLR.bit.INT = 1;
// Acknowledge this interrupt to receive more interrupts from group 3
PieCtrlRegs.PIEACK.all = PIEACK_GROUP3;
}
interrupt void epwm3_isr(void)
{
// Update the CMPA and CMPB values
update_compare(&epwm3_info);
// Clear INT flag for this timer
EPwm3Regs.ETCLR.bit.INT = 1;
// Acknowledge this interrupt to receive more interrupts from group 3
PieCtrlRegs.PIEACK.all = PIEACK_GROUP3;
}
void InitEPwm1Example()
{
// Setup TBCLK
EPwm1Regs.TBPRD = EPWM1_TIMER_TBPRD; // Set timer period 801 TBCLKs
EPwm1Regs.TBPHS.half.TBPHS = 0x0000; // Phase is 0