text: /******************************************************************************
  *
  * Copyright (C) 2005 - 2015 Xilinx, Inc.  All rights reserved.
  *
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  * of this software and associated documentation files (the "Software"), to deal
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  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
  *
  * Use of the Software is limited solely to applications:
  * (a) running on a Xilinx device, or
  * (b) that interact with a Xilinx device through a bus or interconnect.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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  * in advertising or otherwise to promote the sale, use or other dealings in
  * this Software without prior written authorization from Xilinx.
  *
  ******************************************************************************/
  /*****************************************************************************/
  /**
  * @file xgpio_tapp_example.c
  *
  * This file contains a example for using AXI GPIO hardware and driver.
  * This example assumes that there is a UART Device or STDIO Device in the
  * hardware system.
  *
  * @note
  *
  * None
  *
  * <pre>
  * MODIFICATION HISTORY:
  *
  * Ver	Who  Date	  Changes
  * ----- ---- -------- -----------------------------------------------
  * 1.00a sv   04/15/05 Initial release for TestApp integration.
  * 3.00a sv   11/21/09 Updated to use HAL Processor APIs.
  * 3.01a bss  04/18/13 Removed incorrect Documentation lines.(CR #701641)
  * 4.1   lks  11/18/15 Updated to use canonical xparameters and
  *		      clean up of the comments and code for CR 900381
  * 4.3   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.
  * </pre>
  *
  *****************************************************************************/
  
  /***************************** Include Files ********************************/
  
  #include "xparameters.h"
  #include "xgpio.h"
  #include "stdio.h"
  #include "xstatus.h"
  #include "xil_printf.h"
  
  /************************** Constant Definitions ****************************/
  
  /*
   * 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	  1000000
  
  /* The following constant is used to determine which channel of the GPIO is
   * used if there are 2 channels supported in the GPIO.
   */
  #define LED_CHANNEL 1
  
  #define LED_MAX_BLINK	0x1	/* Number of times the LED Blinks */
  
  #define GPIO_BITWIDTH	16	/* This is the width of the GPIO */
  
  #define printf xil_printf	/* A smaller footprint printf */
  
  /*
   * 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.
   */
  #ifndef TESTAPP_GEN
  #define GPIO_OUTPUT_DEVICE_ID	XPAR_GPIO_0_DEVICE_ID
  #define GPIO_INPUT_DEVICE_ID	XPAR_GPIO_0_DEVICE_ID
  #endif /* TESTAPP_GEN */
  
  /**************************** Type Definitions ******************************/
  
  
  /***************** Macros (Inline Functions) Definitions *******************/
  
  
  /************************** Function Prototypes ****************************/
  
  int GpioOutputExample(u16 DeviceId, u32 GpioWidth);
  
  int GpioInputExample(u16 DeviceId, u32 *DataRead);
  
  void GpioDriverHandler(void *CallBackRef);
  
  
  /************************** Variable Definitions **************************/
  
  /*
   * The following are declared globally so they are zeroed and so they are
   * easily accessible from a debugger
   */
  XGpio GpioOutput; /* The driver instance for GPIO Device configured as O/P */
  XGpio GpioInput;  /* The driver instance for GPIO Device configured as I/P */
  
  /*****************************************************************************/
  /**
  * Main function to call the example. This function is not included if the
  * example is generated from the Peripheral Tests in SDK.
  *
  * @param	None
  *
  * @return
  *		- XST_SUCCESS if successful
  *		- XST_FAILURE if unsuccessful
  *
  * @note		None
  *
  ******************************************************************************/
  #ifndef TESTAPP_GEN
  int main(void)
  {
  	int Status;
  	u32 InputData;
  
  	Status = GpioOutputExample(GPIO_OUTPUT_DEVICE_ID, GPIO_BITWIDTH);
  	if (Status != XST_SUCCESS) {
  		xil_printf("Gpio tapp Example Failed\r\n");
  		  return XST_FAILURE;
  	}
  
  	Status = GpioInputExample(GPIO_INPUT_DEVICE_ID, &InputData);
  	if (Status != XST_SUCCESS) {
  		xil_printf("Gpio tapp Example Failed\r\n");
  		  return XST_FAILURE;
  	}
  
  	printf("Data read from GPIO Input is  0x%x \n\r", (int)InputData);
  
  	xil_printf("Successfully ran Gpio tapp Example\r\n");
  	return XST_SUCCESS;
  }
  #endif
  
  
  /*****************************************************************************/
  /**
  *
  * This function does a minimal test on the GPIO device configured as OUTPUT
  * and driver as a example.
  *
  *
  * @param	DeviceId is the XPAR_<GPIO_instance>_DEVICE_ID value from
  *		xparameters.h
  * @param	GpioWidth is the width of the GPIO
  *
  * @return
  *		- XST_SUCCESS if successful
  *		- XST_FAILURE if unsuccessful
  *
  * @note		None
  *
  ****************************************************************************/
  int GpioOutputExample(u16 DeviceId, u32 GpioWidth)
  {
  	volatile int Delay;
  	u32 LedBit;
  	u32 LedLoop;
  	int Status;
  
  	/*
  	 * Initialize the GPIO driver so that it's ready to use,
  	 * specify the device ID that is generated in xparameters.h
  	 */
  	 Status = XGpio_Initialize(&GpioOutput, DeviceId);
  	 if (Status != XST_SUCCESS)  {
  		  return XST_FAILURE;
  	 }
  
  	 /* Set the direction for all signals to be outputs */
  	 XGpio_SetDataDirection(&GpioOutput, LED_CHANNEL, 0x0);
  
  	 /* Set the GPIO outputs to low */
  	 XGpio_DiscreteWrite(&GpioOutput, LED_CHANNEL, 0x0);
  
  	 for (LedBit = 0x0; LedBit < GpioWidth; LedBit++)  {
  
  		for (LedLoop = 0; LedLoop < LED_MAX_BLINK; LedLoop++) {
  
  			/* Set the GPIO Output to High */
  			XGpio_DiscreteWrite(&GpioOutput, LED_CHANNEL,
  						1 << LedBit);
  
  #ifndef __SIM__
  			/* Wait a small amount of time so the LED is visible */
  			for (Delay = 0; Delay < LED_DELAY; Delay++);
  
  #endif
  			/* Clear the GPIO Output */
  			XGpio_DiscreteClear(&GpioOutput, LED_CHANNEL,
  						1 << LedBit);
  
  
  #ifndef __SIM__
  			/* Wait a small amount of time so the LED is visible */
  			for (Delay = 0; Delay < LED_DELAY; Delay++);
  #endif
  
  		  }
  
  	 }
  
  	 return XST_SUCCESS;
  
  }
  
  
  /******************************************************************************/
  /**
  *
  * This function  performs a test on the GPIO driver/device with the GPIO
  * configured as INPUT
  *
  * @param	DeviceId is the XPAR_<GPIO_instance>_DEVICE_ID value from
  *		xparameters.h
  * @param	DataRead is the pointer where the data read from GPIO Input is
  *		returned
  *
  * @return
  *		- XST_SUCCESS if the Test is successful
  *		- XST_FAILURE if the test is not successful
  *
  * @note	  	None.
  *
  ******************************************************************************/
  int GpioInputExample(u16 DeviceId, u32 *DataRead)
  {
  	 int Status;
  
  	 /*
  	  * Initialize the GPIO driver so that it's ready to use,
  	  * specify the device ID that is generated in xparameters.h
  	  */
  	 Status = XGpio_Initialize(&GpioInput, DeviceId);
  	 if (Status != XST_SUCCESS) {
  		  return XST_FAILURE;
  	 }
  
  	 /* Set the direction for all signals to be inputs */
  	 XGpio_SetDataDirection(&GpioInput, LED_CHANNEL, 0xFFFFFFFF);
  
  	 /* Read the state of the data so that it can be  verified */
  	 *DataRead = XGpio_DiscreteRead(&GpioInput, LED_CHANNEL);
  
  	 return XST_SUCCESS;
  
  }
  
  