/******************************************************************************
* Copyright (C) 2002 - 2021 Xilinx, Inc.  All rights reserved.
* SPDX-License-Identifier: MIT
******************************************************************************/

/*****************************************************************************/
/**
* @file xgpio_example.c
*
* This file contains a design example using the AXI GPIO driver (XGpio) and
* hardware device.  It only uses channel 1 of a GPIO device and assumes that
* the bit 0 of the GPIO is connected to the LED on the HW board.
*
*
* <pre>
* MODIFICATION HISTORY:
*
* Ver   Who  Date     Changes
* ----- ---- -------- -----------------------------------------------
* 1.00a rmm  03/13/02 First release
* 1.00a rpm  08/04/03 Removed second example and invalid macro calls
* 2.00a jhl  12/15/03 Added support for dual channels
* 2.00a sv   04/20/05 Minor changes to comply to Doxygen and coding guidelines
* 3.00a ktn  11/20/09 Minor changes as per coding guidelines.
* 4.1   lks  11/18/15 Updated to use canonical xparameters and
*		      clean up of the comments and code for CR 900381
* 4.3   sk   09/29/16 Modified the example to make it work when LED_bits are
*                     configured as an output. CR# 958644
*       ms   01/23/17 Added xil_printf statement in main function to
*                     ensure that "Successfully ran" and "Failed" strings
*                     are available in all examples. This is a fix for
*                     CR-965028.
* 4.5  sne   06/12/19 Fixed IAR compiler warning.
*
* </pre>
******************************************************************************/

/***************************** Include Files *********************************/

#include "xparameters.h"
#include "xgpio.h"
#include "xil_printf.h"

/************************** Constant Definitions *****************************/

#define LED 0x01   /* Assumes bit 0 of GPIO is connected to an LED  */

/*
 * The following constants map to the XPAR parameters created in the
 * xparameters.h file. They are defined here such that a user can easily
 * change all the needed parameters in one place.
 */
#define GPIO_EXAMPLE_DEVICE_ID  XPAR_GPIO_0_DEVICE_ID

/*
 * The following constant is used to wait after an LED is turned on to make
 * sure that it is visible to the human eye.  This constant might need to be
 * tuned for faster or slower processor speeds.
 */
#define LED_DELAY     10000000

/*
 * The following constant is used to determine which channel of the GPIO is
 * used for the LED if there are 2 channels supported.
 */
#define LED_CHANNEL 1

/**************************** Type Definitions *******************************/


/***************** Macros (Inline Functions) Definitions *********************/

#ifdef PRE_2_00A_APPLICATION

/*
 * The following macros are provided to allow an application to compile that
 * uses an older version of the driver (pre 2.00a) which did not have a channel
 * parameter. Note that the channel parameter is fixed as channel 1.
 */
#define XGpio_SetDataDirection(InstancePtr, DirectionMask) \
        XGpio_SetDataDirection(InstancePtr, LED_CHANNEL, DirectionMask)

#define XGpio_DiscreteRead(InstancePtr) \
        XGpio_DiscreteRead(InstancePtr, LED_CHANNEL)

#define XGpio_DiscreteWrite(InstancePtr, Mask) \
        XGpio_DiscreteWrite(InstancePtr, LED_CHANNEL, Mask)

#define XGpio_DiscreteSet(InstancePtr, Mask) \
        XGpio_DiscreteSet(InstancePtr, LED_CHANNEL, Mask)

#endif

/************************** Function Prototypes ******************************/


/************************** Variable Definitions *****************************/

/*
 * The following are declared globally so they are zeroed and so they are
 * easily accessible from a debugger
 */

XGpio Gpio; /* The Instance of the GPIO Driver */

/*****************************************************************************/
/**
*
* The purpose of this function is to illustrate how to use the GPIO
* driver to turn on and off an LED.
*
*
* @return	XST_FAILURE to indicate that the GPIO Initialization had
*		failed.
*
* @note		This function will not return if the test is running.
*
******************************************************************************/
int main(void)
{
	int Status;
	volatile int Delay;

	/* Initialize the GPIO driver */
	Status = XGpio_Initialize(&Gpio, GPIO_EXAMPLE_DEVICE_ID);
	if (Status != XST_SUCCESS) {
		xil_printf("Gpio Initialization Failed\r\n");
		return XST_FAILURE;
	}

	/* Set the direction for all signals as inputs except the LED output */
	XGpio_SetDataDirection(&Gpio, LED_CHANNEL, ~LED);

	/* Loop forever blinking the LED */

	while (1) {
		/* Set the LED to High */
		XGpio_DiscreteWrite(&Gpio, LED_CHANNEL, LED);

		/* Wait a small amount of time so the LED is visible */
		for (Delay = 0; Delay < LED_DELAY; Delay++);

		/* Clear the LED bit */
		XGpio_DiscreteClear(&Gpio, LED_CHANNEL, LED);

		/* Wait a small amount of time so the LED is visible */
		for (Delay = 0; Delay < LED_DELAY; Delay++);
	}

}