main.c

/******************************************************************************
* File Name:   main.c
*
* Description: This code example features how a LVD block in PSoC 6 can be 
               configured to generate an interrupt when voltage drops below
               a certain level.
*
* Related Document: See README.md
*
*******************************************************************************
* Copyright 2022, Cypress Semiconductor Corporation (an Infineon company) or
* an affiliate of Cypress Semiconductor Corporation.  All rights reserved.
*
* This software, including source code, documentation and related
* materials ("Software") is owned by Cypress Semiconductor Corporation
* or one of its affiliates ("Cypress") and is protected by and subject to
* worldwide patent protection (United States and foreign),
* United States copyright laws and international treaty provisions.
* Therefore, you may use this Software only as provided in the license
* agreement accompanying the software package from which you
* obtained this Software ("EULA").
* If no EULA applies, Cypress hereby grants you a personal, non-exclusive,
* non-transferable license to copy, modify, and compile the Software
* source code solely for use in connection with Cypress's
* integrated circuit products.  Any reproduction, modification, translation,
* compilation, or representation of this Software except as specified
* above is prohibited without the express written permission of Cypress.
*
* Disclaimer: THIS SOFTWARE IS PROVIDED AS-IS, WITH NO WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, NONINFRINGEMENT, IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. Cypress
* reserves the right to make changes to the Software without notice. Cypress
* does not assume any liability arising out of the application or use of the
* Software or any product or circuit described in the Software. Cypress does
* not authorize its products for use in any products where a malfunction or
* failure of the Cypress product may reasonably be expected to result in
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*******************************************************************************/

/*******************************************************************************
 * Include header files
 ******************************************************************************/
#include "cy_pdl.h"
#include "cyhal.h"
#include "cybsp.h"

/*******************************************************************************
* Macros
********************************************************************************/
#define LVD_INTERRUPT_PRIORITY   2UL
#define DELAY                    1000UL

/*******************************************************************************
* Function Prototypes
********************************************************************************/
void lvd_init(void);
void lvd_interrupt_handler(void);

/*******************************************************************************
* Global Variables
********************************************************************************/
/* LVD interrupt configuration */
const cy_stc_sysint_t lvd_interrupt_cfg =
{
    .intrSrc =      srss_interrupt_IRQn,
    .intrPriority = LVD_INTERRUPT_PRIORITY
};

/* Flag to check the status of LVD interrupt */
uint32_t interrupt_flag = 0;


/*******************************************************************************
* Function Name: main
********************************************************************************
* Summary:
*  This is the main function for LVD example. It initializes the LVD block
*  and the user led.
*
* Parameters:
*  void
*
* Return:
*  int
*
*******************************************************************************/
int main(void)
{
    cy_rslt_t result;

    /* Initialize the device and board peripherals */
    result = cybsp_init() ;
    if (result != CY_RSLT_SUCCESS)
    {
        CY_ASSERT(0);
    }

    /* Enable global interrupts */
    __enable_irq();

    /* Initialize user led as output with strong drive mode and initial value = true*/
    cyhal_gpio_init(CYBSP_USER_LED, CYHAL_GPIO_DIR_OUTPUT, CYHAL_GPIO_DRIVE_STRONG, true);

    /* Initialize the LVD block */
    lvd_init();

    for(;;)
    {
        /* Verify if the LVD interrupt was generated by checking if the interrupt flag is set */
        if (interrupt_flag)
        {
            /* Blink the led in case of LVD interrupt */
            cyhal_gpio_write(CYBSP_USER_LED, false);
            cyhal_system_delay_ms(DELAY);
            cyhal_gpio_write(CYBSP_USER_LED, true);

            /* Reset the interrupt flag to zero */
            interrupt_flag = 0;

        }
    }
}


/***************************************************************************
* Function Name: lvd_init
****************************************************************************
* Summary:
*  This function initializes and configures the LVD block
*
**************************************************************************/
void lvd_init()
{
    /* Disable LVD interrupts */
    Cy_LVD_ClearInterruptMask();

    /* Set the threshold value for monitoring the VDDD voltage */
    Cy_LVD_SetThreshold(CY_LVD_THRESHOLD_2_7_V) ;

    /* Set configuration for LVD interrupt */
    Cy_LVD_SetInterruptConfig(CY_LVD_INTR_BOTH);

    /* Enable the LVD Block */
    Cy_LVD_Enable();

    /* Provide delay to avoid false interrupt detection */
    Cy_SysLib_DelayUs(20U);

    /* Clear any false interrupt */
    Cy_LVD_ClearInterrupt();

    /* Initialize the LVD interrupt */
    (void)Cy_SysInt_Init(&lvd_interrupt_cfg, lvd_interrupt_handler);

    /* Enables LVD interrupts */
    Cy_LVD_SetInterruptMask();
    NVIC_EnableIRQ(lvd_interrupt_cfg.intrSrc);
}


/***************************************************************************
* Function Name: lvd_interrupt_handler
****************************************************************************
* Summary:
*  This function processes the LVD interrupts
*
***************************************************************************/
void lvd_interrupt_handler()
{
    cy_en_lvd_status_t voltage_status = 0;
    uint32_t interrupt_status = 0;

    /* Get the status of interrupt and Voltage */
    interrupt_status = Cy_LVD_GetInterruptStatus();
    voltage_status = Cy_LVD_GetStatus();

    /* Set the flag in case of an interrupt */
    interrupt_flag = 1;

    if((interrupt_status == CY_LVD_INTR ) && (voltage_status == CY_LVD_STATUS_BELOW))
    {
        /*Do the necessary processing if the voltage drops below the set threshold */
    }

    /* Clear the interrupt */
    Cy_LVD_ClearInterrupt();
}

/* [] END OF FILE */