TMS570LC4357: Explaination of example_adcDisplay code of TMS570LC4357

/** @example example_adcDisplay.c
*   This is an example which describes the steps to create an example application which 
*   configures ADC to start conversion ona GIO trigger and display it over an uart .
*   The digital value can be viewed on a pc terminal with the uart configures @ 9600
*   no parity ,2 stop bits.
*
*   
*   @b Step @b 1:
*
*   Create a new project.
*
*   Navigate: -> File -> New -> Project
*
*   @image html example_createProject.JPG "Figure: Create a new Project"
*
*   @b Step @b 2:
*
*   Configure driver code generation: 
*   - Enable GIO driver
*   - Enable SCI driver
*   - Enable ADC driver
*   - Disable others
*
*   Navigate: -> TMS570LCxx /RM5x -> Enable Drivers
*
*   @image html adcDisplay_enabledriver.JPG "Figure: SCI Enable Driver"
*
*
*   @b Step @b 3:
*
*   Navigate: -> TMS570LCxx /RM5x -> ADC
*
*   Configure ADC General : 
*
*   @image html adcDisplay1.JPG "Figure: ADC General Configuration"
*
*
*   @b Step @b 4:
*
*   Configure ADC Group1 : 
*
*   - Configure ADC Group 1 with "Hardware trigger" source as "GIOB0" at "Rising edge"
*   - Enable ADC1 Group 1 channel selection Pin 0 and Pin 1
*
*   @image html adcDisplay2.JPG "Figure: ADC Group Configuration"
*
*   @b Step @b 5:
*
*   Configure SCI: 
*   - Configure SCI baudrate as 9600
*
*   Navigate: -> TMS570LCxx /RM5x -> ADC
*
*   @image html sci_uart1.JPG "Figure: SCI Configuration"
*
*   @b Step @b 6:
*
*   Copy the source code below into your sys_main.c or replace sys_main.c with this file.
*
*   The example file can also be found in the examples folder: ../HALCoGen/examples
*
*   @note HALCoGen generates an empty main function in sys_main.c, 
*         please make sure that you link in the right main function or copy the source into the user code sections of this file.
*
*
*/

/* 
* Copyright (C) 2009-2015 Texas Instruments Incorporated - 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,
*  DATA, OR PROFITS; OR BUSINESS INTERRUPTION HOWEVER CAUSED AND ON ANY
*  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.
*
*/

/* USER CODE BEGIN (0) */
/* USER CODE END */

/* Include Files */

#include "HL_sys_common.h"
#include "HL_system.h"

/* USER CODE BEGIN (1) */

#include "HL_esm.h"
#include "HL_adc.h"
#include "HL_sci.h"
#include "HL_gio.h"

#define  TSIZE1 12
uint8  TEXT1[TSIZE1]= {'\r','\n','|','\t','C','H','.','I','D','=','0','x'};
#define  TSIZE2 9
uint8  TEXT2[TSIZE2]= {'\t','V','A','L','U','E','=','0','x'};


adcData_t adc_data[2];
void sciDisplayText(sciBASE_t *sci, uint8 *text, uint32 length);
void sciDisplayData(sciBASE_t *sci, uint8 *text,uint32 length);
void wait(uint32 time);

/* USER CODE END */

/** @fn void main(void)
*   @brief Application main function
*   @note This function is empty by default.
*
*   This function is called after startup.
*   The user can use this function to implement the application.
*/

/* USER CODE BEGIN (2) */
/* USER CODE END */

void main(void)
{
/* USER CODE BEGIN (3) */
	   uint32 ch_count=0;
	    uint32 id    =0;
	    uint32 value =0;

	    /* initialize gio     */
	    gioInit();
	    gioSetDirection(gioPORTB, 1);

	    /* initialize sci/sci-lin  : even parity , 2 stop bits */
	    sciInit();

	    /* initialize ADC  */
	    /* Group1 -> Channel 0 and 1                        */
	    /* HW trigger trigger source as GIOB  Pin 0         */
	    adcInit();

	    /* start adc conversion */
	    adcStartConversion(adcREG1,adcGROUP1);

	    while(1) /* ... continue forever */
	    {
	        /* trigger using gio port b, pin 0  */
	        gioSetBit(gioPORTB, 0, 1);

	        /* ... wait and read the conversion count */
	        while((adcIsConversionComplete(adcREG1,adcGROUP1))==0);
	        ch_count = adcGetData(adcREG1, adcGROUP1,&adc_data[0]);

	        ch_count = ch_count;
	        /* conversion results :                                       */
	        /* adc_data[0] -> should have conversions for Group1 channel1 */
	        /* adc_data[1] -> should have conversions for Group1 channel2 */

	        id    = adc_data[0].id;
	        value = adc_data[0].value;

	        gioSetBit(gioPORTB, 0, 0);

	        sciDisplayText(sciREG1,&TEXT1[0],TSIZE1);   /* send text 1 */
	        sciDisplayData(sciREG1,(uint8*)&id,4);    /* send data 1 */
	        sciDisplayText(sciREG1,&TEXT2[0],TSIZE2);   /* send text 2 */
	        sciDisplayData(sciREG1,(uint8*)&value,4); /* send data 2 */

	        id    = adc_data[1].id;
	        value = adc_data[1].value;

	        sciDisplayText(sciREG1,&TEXT1[0],TSIZE1);   /* send text 1 */
	        sciDisplayData(sciREG1,(uint8*)&id,4);    /* send data 1 */
	        sciDisplayText(sciREG1,&TEXT2[0],TSIZE2);   /* send text 2 */
	        sciDisplayData(sciREG1,(uint8*)&value,4); /* send data 2 */

	        wait(0xFFFFF);
	    };

/* USER CODE END */
}

/* USER CODE BEGIN (4) */
void sciDisplayData(sciBASE_t *sci, uint8 *text,uint32 length)
{
    uint8 txt = 0;
    uint8 txt1 = 0;

#if ((__little_endian__ == 1) || (__LITTLE_ENDIAN__ == 1))
text = text + (length -1);
#endif

    while(length--)
    {
#if ((__little_endian__ == 1) || (__LITTLE_ENDIAN__ == 1))
        txt = *text--;
#else
        txt = *text++;
#endif

        txt1 = txt;

        txt  &= ~(0xF0);
        txt1 &= ~(0x0F);
        txt1  =txt1>>4;

        if(txt<=0x9)
        {
            txt +=0x30;
        }
        else if(txt > 0x9 && txt < 0xF)
        {
            txt +=0x37;
        }
        else
        {
            txt = 0x30;
        }

        if(txt1 <= 0x9)
        {
            txt1 +=0x30;
        }
        else if((txt1 > 0x9) && (txt1 <= 0xF))
        {
            txt1 +=0x37;
        }
        else
        {
            txt1 = 0x30;
        }

        while ((sciREG1->FLR & 0x4) == 4); /* wait until busy */
        sciSendByte(sciREG1,txt1);      /* send out text   */
        while ((sciREG1->FLR & 0x4) == 4); /* wait until busy */
        sciSendByte(sciREG1,txt);      /* send out text   */
    };
}

void sciDisplayText(sciBASE_t *sci, uint8 *text,uint32 length)
{
    while(length--)
    {
        while ((sciREG1->FLR & 0x4) == 4); /* wait until busy */
        sciSendByte(sciREG1,*text++);      /* send out text   */
    };
}

void wait(uint32 time)
{
    while(time){time--;};
}
/* USER CODE END */