TMS320F28335: GPIO16_External Interrupt is not working

Hi Dipak,

Sorry for the delay wasn't able to find the board to test the code.

Finally today I was able to find an old control card to test the code and I have attached the modified example that works on my end for XINT1,2,3

For XINT3-7 there is a catch that it only works with GPIO32-63 as shown in the user manual screenshot below.

In the code below I assigned GPIO33 as XINT3 source and it works as expected.

Let me know if you have any further issues so we can close this thread after you verified its working on your end as well.

Thanks.

//###########################################################################
//
// FILE:	Example_2833xExternalInterrupt.c
//
// TITLE:	External Interrupt Example
//
//! \addtogroup f2833x_example_list
//! <h1>External Interrupt (external_interrupt)</h1>
//!
//! This program sets up GPIO0 as XINT1 and GPIO1 as XINT2.  Two other
//! GPIO signals are used to trigger the interrupt (GPIO30 triggers
//! XINT1 and GPIO31 triggers XINT2). XINT1 input is synched to SYSCLKOUT
//! XINT2 has a long qualification - 6 samples at 510*SYSCLKOUT each.
//! GPIO34 will go high outside of the interrupts and low within the
//! interrupts. This signal can be monitored on a scope.
//! Each interrupt is fired in sequence - XINT1 first and then XINT2 AND THEN xint3
//!
//! Monitor GPIO34 with an oscilloscope. GPIO34 will be high outside of
//! the ISRs and low within each ISR.
//!
//! \b External \b Connections \n
//!  - Connect GPIO30 to GPIO0. GPIO0 is assigned to XINT1
//!  - Connect GPIO31 to GPIO1. GPIO1 is assigned to XINT2
//!  - Connect GPIO29 to GPIO33. GPIO33 is assigned to XINT3
//!
//! \b Watch \b Variables \n
//!  - Xint1Count - XINT1 interrupt count
//!  - Xint2Count - XINT2 interrupt count
//!  - LoopCount  - Idle loop count
//
//###########################################################################
// $TI Release: $
// $Release Date: $
// $Copyright:
// Copyright (C) 2009-2024 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.
// 
//   Neither the name of Texas Instruments Incorporated nor the names of
//   its contributors may be used to endorse or promote products derived
//   from this software without specific prior written permission.
// 
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// $
//###########################################################################

//
// Included Files
//
#include "DSP28x_Project.h"     // Device Headerfile and Examples Include File

//
// Function Prototypes
//
__interrupt void xint1_isr(void);
__interrupt void xint2_isr(void);
__interrupt void xint3_isr(void);

//
// Globals
//
volatile Uint32 Xint1Count;
volatile Uint32 Xint2Count;
volatile Uint32 Xint3Count;
Uint32 LoopCount;

//
// Defines
//
#define DELAY 35.700L

//
// Main
//
void main(void)
{
    Uint32 TempX1Count;
    Uint32 TempX2Count;
    Uint32 TempX3Count;

    //
    // 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 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.XINT1 = &xint1_isr;
    PieVectTable.XINT2 = &xint2_isr;
    PieVectTable.XINT3 = &xint3_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

    //
    // Step 5. User specific code, enable interrupts
    //

    //
    // Clear the counters
    //
    Xint1Count = 0; // Count Xint1 interrupts
    Xint2Count = 0; // Count XINT2 interrupts
    Xint3Count = 0; // Count XINT2 interrupts

    LoopCount = 0;  // Count times through idle loop

    //
    // Enable Xint1 and XINT2 in the PIE: Group 1 interrupt 4 & 5
    // Enable int1 which is connected to WAKEINT:
    //
    PieCtrlRegs.PIECTRL.bit.ENPIE = 1;          // Enable the PIE block
    PieCtrlRegs.PIEIER1.bit.INTx4 = 1;          // Enable PIE Group 1 INT4
    PieCtrlRegs.PIEIER1.bit.INTx5 = 1;          // Enable PIE Group 1 INT5
    PieCtrlRegs.PIEIER12.bit.INTx1 = 1;         // enable PIE Group 12 INT1
    IER |= M_INT1;                              // Enable CPU int1
    IER |= M_INT12;
    EINT;                                       // Enable Global Interrupts

    //
    // GPIO30 & GPIO31 are outputs, start GPIO30 high and GPIO31 low
    //
    EALLOW;
    GpioDataRegs.GPASET.bit.GPIO30 = 1;         // Load the output latch
    GpioCtrlRegs.GPAMUX2.bit.GPIO30 = 0;        // GPIO
    GpioCtrlRegs.GPADIR.bit.GPIO30 = 1;         // output

    GpioDataRegs.GPACLEAR.bit.GPIO31 = 1;       // Load the output latch
    GpioCtrlRegs.GPAMUX2.bit.GPIO31 = 0;        // GPIO
    GpioCtrlRegs.GPADIR.bit.GPIO31 = 1;         // output

    GpioDataRegs.GPASET.bit.GPIO29 = 1;       // Load the output latch
    GpioCtrlRegs.GPAMUX2.bit.GPIO29 = 0;        // GPIO
    GpioCtrlRegs.GPADIR.bit.GPIO29 = 1;         // output

    EDIS;

    //
    // GPIO0 and GPIO1 are inputs
    //
    EALLOW;
    GpioCtrlRegs.GPAMUX1.bit.GPIO0 = 0;      // GPIO
    GpioCtrlRegs.GPADIR.bit.GPIO0 = 0;       // input
    GpioCtrlRegs.GPAQSEL1.bit.GPIO0 = 0;     // Xint1 Synch to SYSCLKOUT only

    GpioCtrlRegs.GPAMUX1.bit.GPIO1 = 0;      // GPIO
    GpioCtrlRegs.GPADIR.bit.GPIO1 = 0;       // input
    GpioCtrlRegs.GPAQSEL1.bit.GPIO1 = 2;     // XINT2 Qual using 6 samples
    
    GpioCtrlRegs.GPAMUX1.bit.GPIO2 = 0;      // GPIO
    GpioCtrlRegs.GPADIR.bit.GPIO2 = 0;       // input
    GpioCtrlRegs.GPAQSEL1.bit.GPIO2 = 0;     // Xint3 Synch to SYSCLKOUT only

    //
    // Each sampling window is 510*SYSCLKOUT
    //
    GpioCtrlRegs.GPACTRL.bit.QUALPRD0 = 0xFF;
    EDIS;

    //
    // GPIO0 is XINT1, GPIO1 is XINT2
    //
    EALLOW;
    GpioIntRegs.GPIOXINT1SEL.bit.GPIOSEL = 0;   // Xint1 is GPIO0
    GpioIntRegs.GPIOXINT2SEL.bit.GPIOSEL = 1;   // XINT2 is GPIO1
    GpioIntRegs.GPIOXINT3SEL.bit.GPIOSEL = 1;   // XINT3 is GPIO33 (Refer to User guide) XINT3-7 are assigned to GPIO32-63

    EDIS;

    //
    // Configure XINT1
    //
    XIntruptRegs.XINT1CR.bit.POLARITY = 0;      // Falling edge interrupt
    XIntruptRegs.XINT2CR.bit.POLARITY = 1;      // Rising edge interrupt
    XIntruptRegs.XINT3CR.bit.POLARITY = 0;      // Falling edge interrupt

    //
    // Enable XINT1 and XINT2
    //
    XIntruptRegs.XINT1CR.bit.ENABLE = 1;        // Enable Xint1
    XIntruptRegs.XINT2CR.bit.ENABLE = 1;        // Enable XINT2
    XIntruptRegs.XINT3CR.bit.ENABLE = 1;        // Enable XINT3

    //
    // GPIO34 will go low inside each interrupt.  Monitor this on a scope
    //
    EALLOW;
    GpioCtrlRegs.GPBMUX1.bit.GPIO34 = 0;        // GPIO
    GpioCtrlRegs.GPBDIR.bit.GPIO34 = 1;         // output
    EDIS;

    //
    // Step 6. IDLE loop
    //
    for(;;)
    {
        TempX1Count = Xint1Count;
        TempX2Count = Xint2Count;
        TempX3Count = Xint3Count;

        //
        // Trigger both XINT1
        //
        GpioDataRegs.GPBSET.bit.GPIO34 = 1;   // GPIO34 is high
        GpioDataRegs.GPACLEAR.bit.GPIO30 = 1; // Lower GPIO30, trigger Xint1
        while(Xint1Count == TempX1Count)
        {
            
        }

        //
        // Trigger both XINT2
        //
        GpioDataRegs.GPBSET.bit.GPIO34 = 1;   // GPIO34 is high
        DELAY_US(DELAY);                      // Wait for Qual period
        GpioDataRegs.GPASET.bit.GPIO31 = 1;   // Raise GPIO31, trigger XINT2
        while(Xint2Count == TempX2Count)
        {
            
        }

        GpioDataRegs.GPBSET.bit.GPIO34 = 1;   // GPIO34 is high
        GpioDataRegs.GPACLEAR.bit.GPIO29 = 1; // Lower GPIO29, trigger Xint3
        while(Xint3Count == TempX3Count)
        {

        }

        //
        // Check that the counts were incremented properly and get ready
        // to start over.
        //
        if(Xint1Count == TempX1Count+1 && Xint2Count == TempX2Count+1 && Xint3Count == TempX3Count+1)
        {
            LoopCount++;
            GpioDataRegs.GPASET.bit.GPIO30 = 1;   // raise GPIO30
            GpioDataRegs.GPACLEAR.bit.GPIO31 = 1; // lower GPIO31
            GpioDataRegs.GPASET.bit.GPIO29 = 1;   // raise GPIO30
        }
        else
        {
            __asm("      ESTOP0"); // stop here
        }
    }
}

//
// Step 7. Insert all local Interrupt Service Routines (ISRs) and 
// functions here
//

//
// Note: If local ISRs are used, reassign vector addresses in vector table as
// shown in Step 5
//

//
// xint1_isr -
//
__interrupt void 
xint1_isr(void)
{
    GpioDataRegs.GPBCLEAR.bit.GPIO34 = 0x1;   // GPIO34 is low
    Xint1Count++;

    //
    // Acknowledge this interrupt to get more from group 1
    //
    PieCtrlRegs.PIEACK.all = PIEACK_GROUP1;
}

//
// xint2_isr -
//
__interrupt void 
xint2_isr(void)
{
    GpioDataRegs.GPBCLEAR.bit.GPIO34 = 0x1;   // GPIO34 is low
    Xint2Count++;

    //
    // Acknowledge this interrupt to get more from group 1
    //
    PieCtrlRegs.PIEACK.all = PIEACK_GROUP1;
}

__interrupt void
xint3_isr(void)
{
    GpioDataRegs.GPBCLEAR.bit.GPIO34 = 0x1;   // GPIO34 is low
    Xint3Count++;
    //
    // Acknowledge this interrupt to get more from group 12
    //
    PieCtrlRegs.PIEACK.all = PIEACK_GROUP12;
}
//
// End of File
//