Touch Panel TFT Library
  mikroC PRO for PIC Libraries > Hardware Libraries > 
  

Touch Panel TFT Library

The mikroC PRO for PIC provides a library for working with Touch Panel for TFT.

  Note :

Library Dependency Tree

Touch Panel TFT Library Dependency Tree

External dependencies of Touch Panel TFT Library

The following variables must be defined in all projects using Touch Panel TFT Library: Description : Example :
extern sfr sbit DriveX_Left; DriveX_Left line. sbit DriveX_Left at LATA0_bit;
extern sfr sbit DriveX_Right; DriveX_Right line. sbit DriveX_Right at LATA1_bit;
extern sfr sbit DriveY_Up; DriveY_Up line. sbit DriveY_Up at LATA2_bit;
extern sfr sbit DriveY_Down; DriveY_Down line. sbit DriveY_Down at LATA3_bit;
extern sfr sbit DriveX_Left_Direction; Direction of the DriveX_Left pin. sbit DriveX_Left_Direction at TRISA0_bit;
extern sfr sbit DriveX_Right_Direction; Direction of the DriveX_Right pin. sbit DriveX_Right_Direction at TRISA1_bit;
extern sfr sbit DriveY_Up_Direction; Direction of the DriveY_Up pin. sbit DriveY_Up_Direction at TRISA2_bit;
extern sfr sbit DriveY_Down_Direction; Direction of the DriveY_Down pin. sbit DriveY_Down_Direction at TRISA3_bit;

Library Routines

TP_TFT_Init

Prototype

void TP_TFT_Init(unsigned int display_width, unsigned int display_height, unsigned int readX_ChNo, unsigned int readY_ChNo);
Description

Initialize TFT touch panel display. Default touch panel ADC threshold value is set to 900.
Parameters
  • display_width: set display width.
  • display_height: set display height.
  • readX_ChNo: read X coordinate from desired ADC channel.
  • readY_ChNo: read Y coordinate from desired ADC channel.
Returns

Nothing.
Requires

Before calling this function initialize ADC module.
Example 
ADC1_Init();                   // Initalize ADC module
TP_TFT_Init(320, 240, 13, 12); // Initialize touch panel
Notes

None.

TP_TFT_Rotate

Prototype

void TP_TFT_Rotate(char);
Description

Rotates touch panel by 180 degrees.
Parameters
  • rotate: set display width. Valid values : 0 - don't rotate, 1 - rotate by 180 degrees.
Returns

Nothing.
Requires

Nothing.
Example 
TP_TFT_Rotate(1);   // rotate Touch Panel by 180 degrees
Notes

None.

TP_TFT_Set_ADC_Threshold

Prototype

void TP_TFT_Set_ADC_Threshold(unsigned int threshold);
Description

Set custom ADC threshold value, call this function after TP_TFT_Init.
Parameters
  • threshold: custom ADC threshold value.
Returns

Nothing.
Requires

TP_TFT_Init has to be called before using this routine.
Example 
TP_TFT_Set_ADC_Threshold(900);    // Set touch panel ADC threshold
Notes

None.

TP_TFT_Press_Detect

Prototype

char TP_TFT_Press_Detect();
Description

Detects if the touch panel has been pressed.
Parameters

None.
Returns
  • 1 - if touch panel is pressed.
  • 0 - otherwise.
Requires

Global variables :

  • DriveX_Left: DriveX_Left pin.
  • DriveX_Right: DriveX_Right pin.
  • DriveY_Up: DriveY_Up pin.
  • DriveY_Down: DriveY_Down pin.
  • DriveX_Left_Direction: Direction of DriveX_Left pin.
  • DriveX_Right_Direction: Direction of DriveX_Right pin.
  • DriveY_Up_Direction: Direction of DriveY_Up pin.
  • DriveY_Down_Direction: Direction of DriveY_Down pin.
must be defined before using this function.
Example 
// Touch Panel module connections
sbit DriveX_Left at LATA0_bit;
sbit DriveX_Right at LATA1_bit;
sbit DriveY_Up at LATA2_bit;
sbit DriveY_Down at LATA3_bit;
sbit DriveX_Left_Direction at TRISA0_bit;
sbit DriveX_Right_Direction at TRISA1_bit;
sbit DriveY_Up_Direction at TRISA2_bit;
sbit DriveY_Down_Direction at TRISA3_bit;
// End Touch Panel module connections

if (TP_TFT_Press_Detect()) {
  ...
}
Notes

None.

TP_TFT_Get_Coordinates

Prototype

char TP_TFT_Get_Coordinates(unsigned int *x_coordinate, unsigned int *y_coordinate);
Description

Get touch panel coordinates and store them in x_coordinate and y_coordinate parameters.
Parameters
  • x_coordinate: x coordinate of the place of touch.
  • y_coordinate: y coordinate of the place of touch.
Returns
  • 0 - if reading is within display dimension range.
  • 1 - if reading is out of display dimension range.
Requires

Nothing.
Example 
if (TP_TFT_Get_Coordinates(&x_coord, &y_coord) == 0) {
 ...
}
Notes

None.

TP_TFT_Calibrate_Min

Prototype

void TP_TFT_Calibrate_Min();
Description

Calibrate bottom left corner of the touch Panel.
Parameters

None.
Returns

Nothing.
Requires

Nothing.
Example 
TP_TFT_Calibrate_Min();    // Calibration of bottom left corner
Notes

None.

TP_TFT_Calibrate_Max

Prototype

void TP_TFT_Calibrate_Max();
Description

Calibrate upper right corner of the touch panel.
Parameters

None.
Returns

Nothing.
Requires

Nothing.
Example 
TP_TFT_Calibrate_Max();    // Calibration of upper right corner
Notes

None.

TP_TFT_Get_Calibration_Consts

Prototype

void TP_TFT_Get_Calibration_Consts(unsigned int *x_min, unsigned int *x_max, unsigned int *y_min, unsigned int *y_max);
Description

Gets calibration constants after calibration is done and stores them in x_min, x_max, y_min and y_max parameters.
Parameters
  • x_min: x coordinate of the bottom left corner of the working area.
  • x_max: x coordinate of the upper right corner of the working area.
  • y_min: y coordinate of the bottom left corner of the working area.
  • y_max: y coordinate of the upper right corner of the working area.
Returns

Nothing.
Requires

Nothing.
Example 
TP_TFT_Get_Calibration_Consts(&x_min, &y_min, &x_max, &y_max);    // Get calibration constants
Notes

None.

TP_TFT_Set_Calibration_Consts

Prototype

void TP_TFT_Set_Calibration_Consts(unsigned int x_min, unsigned int x_max, unsigned int y_min, unsigned int y_max);
Description

Sets calibration constants.
Parameters
  • x_min: x coordinate of the bottom left corner of the working area.
  • x_max: x coordinate of the upper right corner of the working area.
  • y_min: y coordinate of the bottom left corner of the working area.
  • y_max: y coordinate of the upper right corner of the working area.
Returns

Nothing.
Requires

Nothing.
Example 
TP_TFT_Set_Calibration_Consts(173, 776, 75, 760);    // Set calibration constants
Notes

None.

HW Connection

Touch Panel TFT HW connection

Touch Panel TFT HW connection

Copyright (c) 2002-2012 mikroElektronika. All rights reserved.
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