//###########################################################################
//
// FILE: Example_2833xFlash.c
//
// TITLE: ePWM Timer Interrupt From Flash Example
//
//! \addtogroup f2833x_example_list
//! ePWM Timer Interrupt From Flash (flash_f28335)
//!
//! This example runs the ePWM interrupt example from flash. ePwm1 Interrupt
//! will run from RAM and puts the flash into sleep mode. ePwm2 Interrupt
//! will run from RAM and puts the flash into standby mode. ePWM3 Interrupt
//! will run from FLASH. All timers have the same period. The timers are
//! started sync'ed. An interrupt is taken on a zero event for each ePWM
//! timer.GPIO32 is toggled while in the background loop.\n
//! \b Note: \n
//! - ePWM1: takes an interrupt every event
//! - ePWM2: takes an interrupt every 2nd event
//! - ePWM3: takes an interrupt every 3rd event
//!
//! Thus the Interrupt count for ePWM1, ePWM4-ePWM6 should be equal
//! The interrupt count for ePWM2 should be about half that of ePWM1
//! and the interrupt count for ePWM3 should be about 1/3 that of ePWM1
//!
//! Follow these steps to run the program.
//! - Build the project
//! - Flash the .out file into the device.
//! - Set the hardware jumpers to boot to Flash
//! - Use the included GEL file to load the project, symbols
//! defined within the project and the variables into the watch
//! window.
//!
//! Steps that were taken to convert the ePWM example from RAM
//! to Flash execution:
//! - Change the linker cmd file to reflect the flash memory map.
//! - Make sure any initialized sections are mapped to Flash.
//! In SDFlash utility this can be checked by the View->Coff/Hex
//! status utility. Any section marked as "load" should be
//! allocated to Flash.
//! - Make sure there is a branch instruction from the entry to Flash
//! at 0x33FFF6 to the beginning of code execution. This example
//! uses the DSP2833x_CodeStartBranch.__asm file to accomplish this.
//! - Set boot mode Jumpers to "boot to Flash"
//! - For best performance from the flash, modify the waitstates
//! and enable the flash pipeline as shown in this example.
//! Note: any code that manipulates the flash waitstate and pipeline
//! control must be run from RAM. Thus these functions are located
//! in their own memory section called ramfuncs.
//!
//! \b Watch \b Variables \n
//! - EPwm1TimerIntCount
//! - EPwm2TimerIntCount
//! - EPwm3TimerIntCount
//
//###########################################################################
// $TI Release: $
// $Release Date: $
// $Copyright:
// Copyright (C) 2009-2023 Texas Instruments Incorporated - http://www.ti.com/
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
//
// Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//
// Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the
// distribution.
//
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//
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// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// $
//###########################################################################
//
// Included Files
//
#include "DSP28x_Project.h" // Device Headerfile and Examples Include File
#include
//
// Defines that configure which ePWM timer interrupts are enabled at
// the PIE level: 1 = enabled, 0 = disabled
//
#define PWM1_INT_ENABLE 1
#define PWM2_INT_ENABLE 1
#define PWM3_INT_ENABLE 1
//
// Defines for the period for each timer
//
#define PWM1_TIMER_TBPRD 0x1FFF
#define PWM2_TIMER_TBPRD 0x1FFF
#define PWM3_TIMER_TBPRD 0x1FFF
//
// Make this long enough so that we can see an LED toggle
//
#define DELAY 1000000L
//
// Functions that will be run from RAM need to be assigned to
// a different section. This section will then be mapped using
// the linker cmd file.
//
#ifdef __TI_COMPILER_VERSION__
#if __TI_COMPILER_VERSION__ >= 15009000
#pragma CODE_SECTION(epwm1_timer_isr, ".TI.ramfunc");
#pragma CODE_SECTION(epwm2_timer_isr, ".TI.ramfunc");
#else
#pragma CODE_SECTION(epwm1_timer_isr, "ramfuncs");
#pragma CODE_SECTION(epwm2_timer_isr, "ramfuncs");
#endif
#endif
//
// Function Prototypes
//
__interrupt void epwm1_timer_isr(void);
__interrupt void epwm2_timer_isr(void);
__interrupt void epwm3_timer_isr(void);
void InitEPwmTimer(void);
//
// Globals
//
Uint32 EPwm1TimerIntCount;
Uint32 EPwm2TimerIntCount;
Uint32 EPwm3TimerIntCount;
Uint32 LoopCount;
//
// These are defined by the linker (see F28335.cmd)
//
extern Uint16 RamfuncsLoadStart;
extern Uint16 RamfuncsLoadEnd;
extern Uint16 RamfuncsRunStart;
extern Uint16 RamfuncsLoadSize;
//
// Main
//
void main(void)
{
//
// Step 1. Initialize System Control:
// PLL, WatchDog, enable Peripheral Clocks
// This example function is found in the DSP2833x_SysCtrl.c file.
//
InitSysCtrl();
//
// Step 2. Initialize 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
//
// 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 = &epwm1_timer_isr;
PieVectTable.EPWM2_INT = &epwm2_timer_isr;
PieVectTable.EPWM3_INT = &epwm3_timer_isr;
EDIS; // This is needed to disable write to EALLOW protected registers
//
// Step 4. Initialize all the Device Peripherals:
// This function is found in DSP2833x_InitPeripherals.c
//
//InitPeripherals(); // Not required for this example
InitEPwmTimer(); // For this example, only initialize the ePWM Timers
//
// Step 5. User specific code, enable interrupts
//
//
// Copy time critical code and Flash setup code to RAM
// This includes the following ISR functions: epwm1_timer_isr(),
// epwm2_timer_isr(), epwm3_timer_isr and and InitFlash();
// The RamfuncsLoadStart, RamfuncsLoadEnd, and RamfuncsRunStart
// symbols are created by the linker. Refer to the F28335.cmd file.
//
memcpy(&RamfuncsRunStart, &RamfuncsLoadStart, (Uint32)&RamfuncsLoadSize);
//
// Call Flash Initialization to setup flash waitstates
// This function must reside in RAM
//
InitFlash();
//
// Initialize counters
//
EPwm1TimerIntCount = 0;
EPwm2TimerIntCount = 0;
EPwm3TimerIntCount = 0;
LoopCount = 0;
//
// 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 = PWM1_INT_ENABLE;
PieCtrlRegs.PIEIER3.bit.INTx2 = PWM2_INT_ENABLE;
PieCtrlRegs.PIEIER3.bit.INTx3 = PWM3_INT_ENABLE;
//
// 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)
//
EALLOW;
GpioCtrlRegs.GPBMUX1.bit.GPIO32 = 0;
GpioCtrlRegs.GPBDIR.bit.GPIO32 = 1;
EDIS;
for(;;)
{
//
// This loop will be interrupted, so the overall
// delay between pin toggles will be longer.
//
DELAY_US(DELAY);
LoopCount++;
GpioDataRegs.GPBTOGGLE.bit.GPIO32 = 1;
}
}
//
// InitEPwmTimer -
//
void
InitEPwmTimer()
{
EALLOW;
SysCtrlRegs.PCLKCR0.bit.TBCLKSYNC = 0; // Stop all the TB clocks
EDIS;
//
// Setup Sync
//
EPwm1Regs.TBCTL.bit.SYNCOSEL = TB_SYNC_IN; // Pass through
EPwm2Regs.TBCTL.bit.SYNCOSEL = TB_SYNC_IN; // Pass through
EPwm3Regs.TBCTL.bit.SYNCOSEL = TB_SYNC_IN; // Pass through
//
// Allow each timer to be sync'ed
//
EPwm1Regs.TBCTL.bit.PHSEN = TB_ENABLE;
EPwm2Regs.TBCTL.bit.PHSEN = TB_ENABLE;
EPwm3Regs.TBCTL.bit.PHSEN = TB_ENABLE;
EPwm1Regs.TBPHS.half.TBPHS = 100;
EPwm2Regs.TBPHS.half.TBPHS = 200;
EPwm3Regs.TBPHS.half.TBPHS = 300;
EPwm1Regs.TBPRD = PWM1_TIMER_TBPRD;
EPwm1Regs.TBCTL.bit.CTRMODE = TB_COUNT_UP; // Count up
EPwm1Regs.ETSEL.bit.INTSEL = ET_CTR_ZERO; // Select INT on Zero event
EPwm1Regs.ETSEL.bit.INTEN = PWM1_INT_ENABLE; // Enable INT
EPwm1Regs.ETPS.bit.INTPRD = ET_1ST; // Generate INT on 1st event
EPwm2Regs.TBPRD = PWM2_TIMER_TBPRD;
EPwm2Regs.TBCTL.bit.CTRMODE = TB_COUNT_UP; // Count up
EPwm2Regs.ETSEL.bit.INTSEL = ET_CTR_ZERO; // Enable INT on Zero event
EPwm2Regs.ETSEL.bit.INTEN = PWM2_INT_ENABLE; // Enable INT
EPwm2Regs.ETPS.bit.INTPRD = ET_2ND; // Generate INT on 2nd event
EPwm3Regs.TBPRD = PWM3_TIMER_TBPRD;
EPwm3Regs.TBCTL.bit.CTRMODE = TB_COUNT_UP; // Count up
EPwm3Regs.ETSEL.bit.INTSEL = ET_CTR_ZERO; // Enable INT on Zero event
EPwm3Regs.ETSEL.bit.INTEN = PWM3_INT_ENABLE; // Enable INT
EPwm3Regs.ETPS.bit.INTPRD = ET_3RD; // Generate INT on 3rd event
EALLOW;
SysCtrlRegs.PCLKCR0.bit.TBCLKSYNC = 1; // Start all the timers synced
EDIS;
}
//
// epwm1_timer_isr -This ISR MUST be executed from RAM as it will put the Flash
// into Sleep Interrupt routines uses in this example
//
__interrupt void
epwm1_timer_isr(void)
{
//
// Put the Flash to sleep
//
EALLOW;
FlashRegs.FPWR.bit.PWR = FLASH_SLEEP;
EDIS;
EPwm1TimerIntCount++;
//
// 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;
}
//
// epwm2_timer_isr - This ISR MUST be executed from RAM as it will put the
// Flash into Standby
//
__interrupt void
epwm2_timer_isr(void)
{
EPwm2TimerIntCount++;
//
// Put the Flash into standby
//
EALLOW;
FlashRegs.FPWR.bit.PWR = FLASH_STANDBY;
EDIS;
//
// 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;
}
//
// epwm3_timer_isr -
//
__interrupt void
epwm3_timer_isr(void)
{
Uint16 i;
EPwm3TimerIntCount++;
//
// Short Delay to simulate some ISR Code
//
for(i = 1; i < 0x01FF; i++)
{
}
//
// 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;
}
//
// End of File
//