Guillermo Stedile / RA8875

Forked para SNOCC

Dependencies:   GPS

Dependents:   SNOCC_V1 SNOCC_V2

Fork of RA8875 by SNOCC

RA8875_Touch.cpp@78:faf49c381591, 2014-12-28 (annotated)

Committer:
WiredHome
Date:
Sun Dec 28 03:14:35 2014 +0000
Revision:
78:faf49c381591
Child:
79:544eb4964795
Continue work on touch screen, and some file refactoring for easier maintenance.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
WiredHome 78:faf49c381591 1 /// This file contains the RA8875 Touch panel methods.
WiredHome 78:faf49c381591 2 ///
WiredHome 78:faf49c381591 3
WiredHome 78:faf49c381591 4 #include "RA8875.h"
WiredHome 78:faf49c381591 5
WiredHome 78:faf49c381591 6 // ### Touch Panel support code additions begin here
WiredHome 78:faf49c381591 7
WiredHome 78:faf49c381591 8 RetCode_t RA8875::TouchPanelInit(void)
WiredHome 78:faf49c381591 9 {
WiredHome 78:faf49c381591 10 //TPCR0: Set enable bit, default sample time, wakeup, and ADC clock
WiredHome 78:faf49c381591 11 WriteCommand(TPCR0, TP_ENABLE | TP_ADC_SAMPLE_DEFAULT_CLKS | TP_ADC_CLKDIV_DEFAULT);
WiredHome 78:faf49c381591 12 // TPCR1: Set auto/manual, Ref voltage, debounce, manual mode params
WiredHome 78:faf49c381591 13 WriteCommand(TPCR1, TP_MODE_DEFAULT | TP_DEBOUNCE_DEFAULT);
WiredHome 78:faf49c381591 14 WriteCommand(INTC1, ReadCommand(INTC1) | RA8875_INT_TP); // reg INTC1: Enable Touch Panel Interrupts (D2 = 1)
WiredHome 78:faf49c381591 15 WriteCommand(INTC2, RA8875_INT_TP); // reg INTC2: Clear any TP interrupt flag
WiredHome 78:faf49c381591 16 return noerror;
WiredHome 78:faf49c381591 17 }
WiredHome 78:faf49c381591 18
WiredHome 78:faf49c381591 19 RetCode_t RA8875::TouchPanelInit(uint8_t bTpEnable, uint8_t bTpAutoManual, uint8_t bTpDebounce, uint8_t bTpManualMode, uint8_t bTpAdcClkDiv, uint8_t bTpAdcSampleTime)
WiredHome 78:faf49c381591 20 {
WiredHome 78:faf49c381591 21 // Parameter bounds check
WiredHome 78:faf49c381591 22 if( \
WiredHome 78:faf49c381591 23 !(bTpEnable == TP_ENABLE || bTpEnable == TP_ENABLE) || \
WiredHome 78:faf49c381591 24 !(bTpAutoManual == TP_MODE_AUTO || bTpAutoManual == TP_MODE_MANUAL) || \
WiredHome 78:faf49c381591 25 !(bTpDebounce == TP_DEBOUNCE_OFF || bTpDebounce == TP_DEBOUNCE_ON) || \
WiredHome 78:faf49c381591 26 !(bTpManualMode <= TP_MANUAL_LATCH_Y) || \
WiredHome 78:faf49c381591 27 !(bTpAdcClkDiv <= TP_ADC_CLKDIV_128) || \
WiredHome 78:faf49c381591 28 !(bTpAdcSampleTime <= TP_ADC_SAMPLE_65536_CLKS) \
WiredHome 78:faf49c381591 29 ) return bad_parameter;
WiredHome 78:faf49c381591 30 // Construct the config byte for TPCR0 and write them
WiredHome 78:faf49c381591 31 WriteCommand(TPCR0, bTpEnable | bTpAdcClkDiv | bTpAdcSampleTime); // Note: Wakeup is never enabled
WiredHome 78:faf49c381591 32 // Construct the config byte for TPCR1 and write them
WiredHome 78:faf49c381591 33 WriteCommand(TPCR1, bTpManualMode | bTpDebounce | bTpManualMode); // Note: Always uses internal Vref.
WiredHome 78:faf49c381591 34 // Set up the interrupt flag and enable bits
WiredHome 78:faf49c381591 35 WriteCommand(INTC1, ReadCommand(INTC1) | RA8875_INT_TP); // reg INTC1: Enable Touch Panel Interrupts (D2 = 1)
WiredHome 78:faf49c381591 36 WriteCommand(INTC2, RA8875_INT_TP); // reg INTC2: Clear any TP interrupt flag
WiredHome 78:faf49c381591 37 return noerror;
WiredHome 78:faf49c381591 38 }
WiredHome 78:faf49c381591 39
WiredHome 78:faf49c381591 40 unsigned char RA8875::TouchPanelRead(loc_t *x, loc_t *y)
WiredHome 78:faf49c381591 41 {
WiredHome 78:faf49c381591 42 unsigned char touchready;
WiredHome 78:faf49c381591 43 static int xbuf[TPBUFSIZE], ybuf[TPBUFSIZE], sample = 0;
WiredHome 78:faf49c381591 44 int i, j, temp;
WiredHome 78:faf49c381591 45
WiredHome 78:faf49c381591 46 if( (ReadCommand(INTC2) & RA8875_INT_TP) ) { // Test for TP Interrupt pending in register INTC2
WiredHome 78:faf49c381591 47 // Get the next data samples
WiredHome 78:faf49c381591 48 ybuf[sample] = ReadCommand(TPYH) << 2 | ( (ReadCommand(TPXYL) & 0xC) >> 2 ); // D[9:2] from reg TPYH, D[1:0] from reg TPXYL[3:2]
WiredHome 78:faf49c381591 49 xbuf[sample] = ReadCommand(TPXH) << 2 | ( (ReadCommand(TPXYL) & 0x3) ); // D[9:2] from reg TPXH, D[1:0] from reg TPXYL[1:0]
WiredHome 78:faf49c381591 50 // Check for a complete set
WiredHome 78:faf49c381591 51 if(++sample == TPBUFSIZE) {
WiredHome 78:faf49c381591 52 // Buffers are full, so process them using Finn's method described in Analog Dialogue No. 44, Feb 2010
WiredHome 78:faf49c381591 53 // This requires sorting the samples in order of size, then discarding the top 25% and
WiredHome 78:faf49c381591 54 // bottom 25% as noise spikes. Finally, the middle 50% of the values are averaged to
WiredHome 78:faf49c381591 55 // reduce Gaussian noise.
WiredHome 78:faf49c381591 56
WiredHome 78:faf49c381591 57 // Sort the Y buffer using an Insertion Sort
WiredHome 78:faf49c381591 58 for(i = 1; i <= TPBUFSIZE; i++) {
WiredHome 78:faf49c381591 59 temp = ybuf[i];
WiredHome 78:faf49c381591 60 j = i;
WiredHome 78:faf49c381591 61 while( j && (ybuf[j-1] > temp) ) {
WiredHome 78:faf49c381591 62 ybuf[j] = ybuf[j-1];
WiredHome 78:faf49c381591 63 j = j-1;
WiredHome 78:faf49c381591 64 }
WiredHome 78:faf49c381591 65 ybuf[j] = temp;
WiredHome 78:faf49c381591 66 } // End of Y sort
WiredHome 78:faf49c381591 67 // Sort the X buffer the same way
WiredHome 78:faf49c381591 68 for(i = 1; i <= TPBUFSIZE; i++) {
WiredHome 78:faf49c381591 69 temp = xbuf[i];
WiredHome 78:faf49c381591 70 j = i;
WiredHome 78:faf49c381591 71 while( j && (xbuf[j-1] > temp) ) {
WiredHome 78:faf49c381591 72 xbuf[j] = xbuf[j-1];
WiredHome 78:faf49c381591 73 j = j-1;
WiredHome 78:faf49c381591 74 }
WiredHome 78:faf49c381591 75 xbuf[j] = temp;
WiredHome 78:faf49c381591 76 } // End of X sort
WiredHome 78:faf49c381591 77 // Average the middle half of the Y values and report them
WiredHome 78:faf49c381591 78 j = 0;
WiredHome 78:faf49c381591 79 for(i = (TPBUFSIZE/4) - 1; i < TPBUFSIZE - TPBUFSIZE/4; i++ ) {
WiredHome 78:faf49c381591 80 j += ybuf[i];
WiredHome 78:faf49c381591 81 }
WiredHome 78:faf49c381591 82 *y = j * (float)2/TPBUFSIZE; // This is the average
WiredHome 78:faf49c381591 83 // Average the middle half of the X values and report them
WiredHome 78:faf49c381591 84 j = 0;
WiredHome 78:faf49c381591 85 for(i = (TPBUFSIZE/4) - 1; i < TPBUFSIZE - TPBUFSIZE/4; i++ ) {
WiredHome 78:faf49c381591 86 j += xbuf[i];
WiredHome 78:faf49c381591 87 }
WiredHome 78:faf49c381591 88 *x = j * (float)2/TPBUFSIZE; // This is the average
WiredHome 78:faf49c381591 89 // Tidy up and return
WiredHome 78:faf49c381591 90 touchready = 1;
WiredHome 78:faf49c381591 91 sample = 0; // Ready to start on the next set of data samples
WiredHome 78:faf49c381591 92 } else {
WiredHome 78:faf49c381591 93 // Buffer not yet full, so do not return any results yet
WiredHome 78:faf49c381591 94 touchready = 0;
WiredHome 78:faf49c381591 95 }
WiredHome 78:faf49c381591 96 WriteCommand(INTC2, RA8875_INT_TP); // reg INTC2: Clear that TP interrupt flag
WiredHome 78:faf49c381591 97 } // End of initial if -- data has been read and processed
WiredHome 78:faf49c381591 98 else
WiredHome 78:faf49c381591 99 touchready = 0; // Touch Panel "Int" was not set
WiredHome 78:faf49c381591 100 return touchready;
WiredHome 78:faf49c381591 101 }
WiredHome 78:faf49c381591 102
WiredHome 78:faf49c381591 103 unsigned char RA8875::TouchPanelReadRaw(loc_t *x, loc_t *y)
WiredHome 78:faf49c381591 104 {
WiredHome 78:faf49c381591 105 unsigned char touchready;
WiredHome 78:faf49c381591 106
WiredHome 78:faf49c381591 107 if( (ReadCommand(INTC2) & RA8875_INT_TP) ) { // Test for TP Interrupt pending in register INTC2
WiredHome 78:faf49c381591 108 *y = ReadCommand(TPYH) << 2 | ( (ReadCommand(TPXYL) & 0xC) >> 2 ); // D[9:2] from reg TPYH, D[1:0] from reg TPXYL[3:2]
WiredHome 78:faf49c381591 109 *x = ReadCommand(TPXH) << 2 | ( (ReadCommand(TPXYL) & 0x3) ); // D[9:2] from reg TPXH, D[1:0] from reg TPXYL[1:0]
WiredHome 78:faf49c381591 110 WriteCommand(INTC2, RA8875_INT_TP); // reg INTC2: Clear that TP interrupt flag
WiredHome 78:faf49c381591 111 touchready = 1;
WiredHome 78:faf49c381591 112 } else
WiredHome 78:faf49c381591 113 touchready = 0;
WiredHome 78:faf49c381591 114 return touchready;
WiredHome 78:faf49c381591 115 }
WiredHome 78:faf49c381591 116
WiredHome 78:faf49c381591 117 /* The following section is derived from Carlos E. Vidales.
WiredHome 78:faf49c381591 118 *
WiredHome 78:faf49c381591 119 * Copyright (c) 2001, Carlos E. Vidales. All rights reserved.
WiredHome 78:faf49c381591 120 *
WiredHome 78:faf49c381591 121 * This sample program was written and put in the public domain
WiredHome 78:faf49c381591 122 * by Carlos E. Vidales. The program is provided "as is"
WiredHome 78:faf49c381591 123 * without warranty of any kind, either expressed or implied.
WiredHome 78:faf49c381591 124 * If you choose to use the program within your own products
WiredHome 78:faf49c381591 125 * you do so at your own risk, and assume the responsibility
WiredHome 78:faf49c381591 126 * for servicing, repairing or correcting the program should
WiredHome 78:faf49c381591 127 * it prove defective in any manner.
WiredHome 78:faf49c381591 128 * You may copy and distribute the program's source code in any
WiredHome 78:faf49c381591 129 * medium, provided that you also include in each copy an
WiredHome 78:faf49c381591 130 * appropriate copyright notice and disclaimer of warranty.
WiredHome 78:faf49c381591 131 * You may also modify this program and distribute copies of
WiredHome 78:faf49c381591 132 * it provided that you include prominent notices stating
WiredHome 78:faf49c381591 133 * that you changed the file(s) and the date of any change,
WiredHome 78:faf49c381591 134 * and that you do not charge any royalties or licenses for
WiredHome 78:faf49c381591 135 * its use.
WiredHome 78:faf49c381591 136 *
WiredHome 78:faf49c381591 137 * This file contains functions that implement calculations
WiredHome 78:faf49c381591 138 * necessary to obtain calibration factors for a touch screen
WiredHome 78:faf49c381591 139 * that suffers from multiple distortion effects: namely,
WiredHome 78:faf49c381591 140 * translation, scaling and rotation.
WiredHome 78:faf49c381591 141 *
WiredHome 78:faf49c381591 142 * The following set of equations represent a valid display
WiredHome 78:faf49c381591 143 * point given a corresponding set of touch screen points:
WiredHome 78:faf49c381591 144 *
WiredHome 78:faf49c381591 145 * /- -\
WiredHome 78:faf49c381591 146 * /- -\ /- -\ | |
WiredHome 78:faf49c381591 147 * | | | | | Xs |
WiredHome 78:faf49c381591 148 * | Xd | | A B C | | |
WiredHome 78:faf49c381591 149 * | | = | | * | Ys |
WiredHome 78:faf49c381591 150 * | Yd | | D E F | | |
WiredHome 78:faf49c381591 151 * | | | | | 1 |
WiredHome 78:faf49c381591 152 * \- -/ \- -/ | |
WiredHome 78:faf49c381591 153 * \- -/
WiredHome 78:faf49c381591 154 * where:
WiredHome 78:faf49c381591 155 * (Xd,Yd) represents the desired display point
WiredHome 78:faf49c381591 156 * coordinates,
WiredHome 78:faf49c381591 157 * (Xs,Ys) represents the available touch screen
WiredHome 78:faf49c381591 158 * coordinates, and the matrix
WiredHome 78:faf49c381591 159 * /- -\
WiredHome 78:faf49c381591 160 * |A,B,C|
WiredHome 78:faf49c381591 161 * |D,E,F| represents the factors used to translate
WiredHome 78:faf49c381591 162 * \- -/ the available touch screen point values
WiredHome 78:faf49c381591 163 * into the corresponding display
WiredHome 78:faf49c381591 164 * coordinates.
WiredHome 78:faf49c381591 165 * Note that for practical considerations, the utilities
WiredHome 78:faf49c381591 166 * within this file do not use the matrix coefficients as
WiredHome 78:faf49c381591 167 * defined above, but instead use the following
WiredHome 78:faf49c381591 168 * equivalents, since floating point math is not used:
WiredHome 78:faf49c381591 169 * A = An/Divider
WiredHome 78:faf49c381591 170 * B = Bn/Divider
WiredHome 78:faf49c381591 171 * C = Cn/Divider
WiredHome 78:faf49c381591 172 * D = Dn/Divider
WiredHome 78:faf49c381591 173 * E = En/Divider
WiredHome 78:faf49c381591 174 * F = Fn/Divider
WiredHome 78:faf49c381591 175 * The functions provided within this file are:
WiredHome 78:faf49c381591 176 * setCalibrationMatrix() - calculates the set of factors
WiredHome 78:faf49c381591 177 * in the above equation, given
WiredHome 78:faf49c381591 178 * three sets of test points.
WiredHome 78:faf49c381591 179 * getDisplayPoint() - returns the actual display
WiredHome 78:faf49c381591 180 * coordinates, given a set of
WiredHome 78:faf49c381591 181 * touch screen coordinates.
WiredHome 78:faf49c381591 182 * translateRawScreenCoordinates() - helper function to transform
WiredHome 78:faf49c381591 183 * raw screen points into values
WiredHome 78:faf49c381591 184 * scaled to the desired display
WiredHome 78:faf49c381591 185 * resolution.
WiredHome 78:faf49c381591 186 */
WiredHome 78:faf49c381591 187
WiredHome 78:faf49c381591 188 /**********************************************************************
WiredHome 78:faf49c381591 189 *
WiredHome 78:faf49c381591 190 * Function: setCalibrationMatrix()
WiredHome 78:faf49c381591 191 *
WiredHome 78:faf49c381591 192 * Description: Calling this function with valid input data
WiredHome 78:faf49c381591 193 * in the display and screen input arguments
WiredHome 78:faf49c381591 194 * causes the calibration factors between the
WiredHome 78:faf49c381591 195 * screen and display points to be calculated,
WiredHome 78:faf49c381591 196 * and the output argument - matrixPtr - to be
WiredHome 78:faf49c381591 197 * populated.
WiredHome 78:faf49c381591 198 *
WiredHome 78:faf49c381591 199 * This function needs to be called only when new
WiredHome 78:faf49c381591 200 * calibration factors are desired.
WiredHome 78:faf49c381591 201 *
WiredHome 78:faf49c381591 202 *
WiredHome 78:faf49c381591 203 * Argument(s): displayPtr (input) - Pointer to an array of three
WiredHome 78:faf49c381591 204 * sample, reference points.
WiredHome 78:faf49c381591 205 * screenPtr (input) - Pointer to the array of touch
WiredHome 78:faf49c381591 206 * screen points corresponding
WiredHome 78:faf49c381591 207 * to the reference display points.
WiredHome 78:faf49c381591 208 * matrixPtr (output) - Pointer to the calibration
WiredHome 78:faf49c381591 209 * matrix computed for the set
WiredHome 78:faf49c381591 210 * of points being provided.
WiredHome 78:faf49c381591 211 *
WiredHome 78:faf49c381591 212 *
WiredHome 78:faf49c381591 213 * From the article text, recall that the matrix coefficients are
WiredHome 78:faf49c381591 214 * resolved to be the following:
WiredHome 78:faf49c381591 215 *
WiredHome 78:faf49c381591 216 *
WiredHome 78:faf49c381591 217 * Divider = (Xs0 - Xs2)*(Ys1 - Ys2) - (Xs1 - Xs2)*(Ys0 - Ys2)
WiredHome 78:faf49c381591 218 *
WiredHome 78:faf49c381591 219 *
WiredHome 78:faf49c381591 220 *
WiredHome 78:faf49c381591 221 * (Xd0 - Xd2)*(Ys1 - Ys2) - (Xd1 - Xd2)*(Ys0 - Ys2)
WiredHome 78:faf49c381591 222 * A = ---------------------------------------------------
WiredHome 78:faf49c381591 223 * Divider
WiredHome 78:faf49c381591 224 *
WiredHome 78:faf49c381591 225 *
WiredHome 78:faf49c381591 226 * (Xs0 - Xs2)*(Xd1 - Xd2) - (Xd0 - Xd2)*(Xs1 - Xs2)
WiredHome 78:faf49c381591 227 * B = ---------------------------------------------------
WiredHome 78:faf49c381591 228 * Divider
WiredHome 78:faf49c381591 229 *
WiredHome 78:faf49c381591 230 *
WiredHome 78:faf49c381591 231 * Ys0*(Xs2*Xd1 - Xs1*Xd2) +
WiredHome 78:faf49c381591 232 * Ys1*(Xs0*Xd2 - Xs2*Xd0) +
WiredHome 78:faf49c381591 233 * Ys2*(Xs1*Xd0 - Xs0*Xd1)
WiredHome 78:faf49c381591 234 * C = ---------------------------------------------------
WiredHome 78:faf49c381591 235 * Divider
WiredHome 78:faf49c381591 236 *
WiredHome 78:faf49c381591 237 *
WiredHome 78:faf49c381591 238 * (Yd0 - Yd2)*(Ys1 - Ys2) - (Yd1 - Yd2)*(Ys0 - Ys2)
WiredHome 78:faf49c381591 239 * D = ---------------------------------------------------
WiredHome 78:faf49c381591 240 * Divider
WiredHome 78:faf49c381591 241 *
WiredHome 78:faf49c381591 242 *
WiredHome 78:faf49c381591 243 * (Xs0 - Xs2)*(Yd1 - Yd2) - (Yd0 - Yd2)*(Xs1 - Xs2)
WiredHome 78:faf49c381591 244 * E = ---------------------------------------------------
WiredHome 78:faf49c381591 245 * Divider
WiredHome 78:faf49c381591 246 *
WiredHome 78:faf49c381591 247 *
WiredHome 78:faf49c381591 248 * Ys0*(Xs2*Yd1 - Xs1*Yd2) +
WiredHome 78:faf49c381591 249 * Ys1*(Xs0*Yd2 - Xs2*Yd0) +
WiredHome 78:faf49c381591 250 * Ys2*(Xs1*Yd0 - Xs0*Yd1)
WiredHome 78:faf49c381591 251 * F = ---------------------------------------------------
WiredHome 78:faf49c381591 252 * Divider
WiredHome 78:faf49c381591 253 *
WiredHome 78:faf49c381591 254 *
WiredHome 78:faf49c381591 255 * Return: OK - the calibration matrix was correctly
WiredHome 78:faf49c381591 256 * calculated and its value is in the
WiredHome 78:faf49c381591 257 * output argument.
WiredHome 78:faf49c381591 258 * NOT_OK - an error was detected and the
WiredHome 78:faf49c381591 259 * function failed to return a valid
WiredHome 78:faf49c381591 260 * set of matrix values.
WiredHome 78:faf49c381591 261 * The only time this sample code returns
WiredHome 78:faf49c381591 262 * NOT_OK is when Divider == 0
WiredHome 78:faf49c381591 263 *
WiredHome 78:faf49c381591 264 *
WiredHome 78:faf49c381591 265 *
WiredHome 78:faf49c381591 266 * NOTE! NOTE! NOTE!
WiredHome 78:faf49c381591 267 *
WiredHome 78:faf49c381591 268 * setCalibrationMatrix() and getDisplayPoint() will do fine
WiredHome 78:faf49c381591 269 * for you as they are, provided that your digitizer
WiredHome 78:faf49c381591 270 * resolution does not exceed 10 bits (1024 values). Higher
WiredHome 78:faf49c381591 271 * resolutions may cause the integer operations to overflow
WiredHome 78:faf49c381591 272 * and return incorrect values. If you wish to use these
WiredHome 78:faf49c381591 273 * functions with digitizer resolutions of 12 bits (4096
WiredHome 78:faf49c381591 274 * values) you will either have to a) use 64-bit signed
WiredHome 78:faf49c381591 275 * integer variables and math, or b) judiciously modify the
WiredHome 78:faf49c381591 276 * operations to scale results by a factor of 2 or even 4.
WiredHome 78:faf49c381591 277 *
WiredHome 78:faf49c381591 278 */
WiredHome 78:faf49c381591 279 RetCode_t RA8875::TouchPanelCalibrate(point_t * displayPtr, point_t * screenPtr, tpMatrix_t * matrixPtr)
WiredHome 78:faf49c381591 280 {
WiredHome 78:faf49c381591 281 RetCode_t retValue = noerror;
WiredHome 78:faf49c381591 282
WiredHome 78:faf49c381591 283 tpMatrix.Divider = ((screenPtr[0].x - screenPtr[2].x) * (screenPtr[1].y - screenPtr[2].y)) -
WiredHome 78:faf49c381591 284 ((screenPtr[1].x - screenPtr[2].x) * (screenPtr[0].y - screenPtr[2].y)) ;
WiredHome 78:faf49c381591 285
WiredHome 78:faf49c381591 286 if( tpMatrix.Divider == 0 ) {
WiredHome 78:faf49c381591 287 retValue = bad_parameter;
WiredHome 78:faf49c381591 288 } else {
WiredHome 78:faf49c381591 289 tpMatrix.An = ((displayPtr[0].x - displayPtr[2].x) * (screenPtr[1].y - screenPtr[2].y)) -
WiredHome 78:faf49c381591 290 ((displayPtr[1].x - displayPtr[2].x) * (screenPtr[0].y - screenPtr[2].y)) ;
WiredHome 78:faf49c381591 291
WiredHome 78:faf49c381591 292 tpMatrix.Bn = ((screenPtr[0].x - screenPtr[2].x) * (displayPtr[1].x - displayPtr[2].x)) -
WiredHome 78:faf49c381591 293 ((displayPtr[0].x - displayPtr[2].x) * (screenPtr[1].x - screenPtr[2].x)) ;
WiredHome 78:faf49c381591 294
WiredHome 78:faf49c381591 295 tpMatrix.Cn = (screenPtr[2].x * displayPtr[1].x - screenPtr[1].x * displayPtr[2].x) * screenPtr[0].y +
WiredHome 78:faf49c381591 296 (screenPtr[0].x * displayPtr[2].x - screenPtr[2].x * displayPtr[0].x) * screenPtr[1].y +
WiredHome 78:faf49c381591 297 (screenPtr[1].x * displayPtr[0].x - screenPtr[0].x * displayPtr[1].x) * screenPtr[2].y ;
WiredHome 78:faf49c381591 298
WiredHome 78:faf49c381591 299 tpMatrix.Dn = ((displayPtr[0].y - displayPtr[2].y) * (screenPtr[1].y - screenPtr[2].y)) -
WiredHome 78:faf49c381591 300 ((displayPtr[1].y - displayPtr[2].y) * (screenPtr[0].y - screenPtr[2].y)) ;
WiredHome 78:faf49c381591 301
WiredHome 78:faf49c381591 302 tpMatrix.En = ((screenPtr[0].x - screenPtr[2].x) * (displayPtr[1].y - displayPtr[2].y)) -
WiredHome 78:faf49c381591 303 ((displayPtr[0].y - displayPtr[2].y) * (screenPtr[1].x - screenPtr[2].x)) ;
WiredHome 78:faf49c381591 304
WiredHome 78:faf49c381591 305 tpMatrix.Fn = (screenPtr[2].x * displayPtr[1].y - screenPtr[1].x * displayPtr[2].y) * screenPtr[0].y +
WiredHome 78:faf49c381591 306 (screenPtr[0].x * displayPtr[2].y - screenPtr[2].x * displayPtr[0].y) * screenPtr[1].y +
WiredHome 78:faf49c381591 307 (screenPtr[1].x * displayPtr[0].y - screenPtr[0].x * displayPtr[1].y) * screenPtr[2].y ;
WiredHome 78:faf49c381591 308 if (matrixPtr)
WiredHome 78:faf49c381591 309 memcpy(matrixPtr, &tpMatrix, sizeof(tpMatrix_t));
WiredHome 78:faf49c381591 310 }
WiredHome 78:faf49c381591 311 return( retValue ) ;
WiredHome 78:faf49c381591 312 }
WiredHome 78:faf49c381591 313
WiredHome 78:faf49c381591 314 /**********************************************************************
WiredHome 78:faf49c381591 315 *
WiredHome 78:faf49c381591 316 * Function: getDisplayPoint()
WiredHome 78:faf49c381591 317 *
WiredHome 78:faf49c381591 318 * Description: Given a valid set of calibration factors and a point
WiredHome 78:faf49c381591 319 * value reported by the touch screen, this function
WiredHome 78:faf49c381591 320 * calculates and returns the true (or closest to true)
WiredHome 78:faf49c381591 321 * display point below the spot where the touch screen
WiredHome 78:faf49c381591 322 * was touched.
WiredHome 78:faf49c381591 323 *
WiredHome 78:faf49c381591 324 *
WiredHome 78:faf49c381591 325 *
WiredHome 78:faf49c381591 326 * Argument(s): displayPtr (output) - Pointer to the calculated
WiredHome 78:faf49c381591 327 * (true) display point.
WiredHome 78:faf49c381591 328 * screenPtr (input) - Pointer to the reported touch
WiredHome 78:faf49c381591 329 * screen point.
WiredHome 78:faf49c381591 330 * matrixPtr (input) - Pointer to calibration factors
WiredHome 78:faf49c381591 331 * matrix previously calculated
WiredHome 78:faf49c381591 332 * from a call to
WiredHome 78:faf49c381591 333 * setCalibrationMatrix()
WiredHome 78:faf49c381591 334 *
WiredHome 78:faf49c381591 335 *
WiredHome 78:faf49c381591 336 * The function simply solves for Xd and Yd by implementing the
WiredHome 78:faf49c381591 337 * computations required by the translation matrix.
WiredHome 78:faf49c381591 338 *
WiredHome 78:faf49c381591 339 * /- -\
WiredHome 78:faf49c381591 340 * /- -\ /- -\ | |
WiredHome 78:faf49c381591 341 * | | | | | Xs |
WiredHome 78:faf49c381591 342 * | Xd | | A B C | | |
WiredHome 78:faf49c381591 343 * | | = | | * | Ys |
WiredHome 78:faf49c381591 344 * | Yd | | D E F | | |
WiredHome 78:faf49c381591 345 * | | | | | 1 |
WiredHome 78:faf49c381591 346 * \- -/ \- -/ | |
WiredHome 78:faf49c381591 347 * \- -/
WiredHome 78:faf49c381591 348 *
WiredHome 78:faf49c381591 349 * It must be kept brief to avoid consuming CPU cycles.
WiredHome 78:faf49c381591 350 *
WiredHome 78:faf49c381591 351 * Return: OK - the display point was correctly calculated
WiredHome 78:faf49c381591 352 * and its value is in the output argument.
WiredHome 78:faf49c381591 353 * NOT_OK - an error was detected and the function
WiredHome 78:faf49c381591 354 * failed to return a valid point.
WiredHome 78:faf49c381591 355 *
WiredHome 78:faf49c381591 356 * NOTE! NOTE! NOTE!
WiredHome 78:faf49c381591 357 *
WiredHome 78:faf49c381591 358 * setCalibrationMatrix() and getDisplayPoint() will do fine
WiredHome 78:faf49c381591 359 * for you as they are, provided that your digitizer
WiredHome 78:faf49c381591 360 * resolution does not exceed 10 bits (1024 values). Higher
WiredHome 78:faf49c381591 361 * resolutions may cause the integer operations to overflow
WiredHome 78:faf49c381591 362 * and return incorrect values. If you wish to use these
WiredHome 78:faf49c381591 363 * functions with digitizer resolutions of 12 bits (4096
WiredHome 78:faf49c381591 364 * values) you will either have to a) use 64-bit signed
WiredHome 78:faf49c381591 365 * integer variables and math, or b) judiciously modify the
WiredHome 78:faf49c381591 366 * operations to scale results by a factor of 2 or even 4.
WiredHome 78:faf49c381591 367 *
WiredHome 78:faf49c381591 368 */
WiredHome 78:faf49c381591 369 RetCode_t RA8875::TouchPanelPoint(point_t * TouchPoint)
WiredHome 78:faf49c381591 370 {
WiredHome 78:faf49c381591 371 RetCode_t retValue = no_touch;
WiredHome 78:faf49c381591 372 point_t screenpoint = {0, 0};
WiredHome 78:faf49c381591 373
WiredHome 78:faf49c381591 374 if (TouchPanelRead(&screenpoint.x, &screenpoint.y)) {
WiredHome 78:faf49c381591 375 retValue = touch;
WiredHome 78:faf49c381591 376 if (tpMatrix.Divider != 0 ) {
WiredHome 78:faf49c381591 377 /* Operation order is important since we are doing integer */
WiredHome 78:faf49c381591 378 /* math. Make sure you add all terms together before */
WiredHome 78:faf49c381591 379 /* dividing, so that the remainder is not rounded off */
WiredHome 78:faf49c381591 380 /* prematurely. */
WiredHome 78:faf49c381591 381 TouchPoint->x = ( (tpMatrix.An * screenpoint.x) +
WiredHome 78:faf49c381591 382 (tpMatrix.Bn * screenpoint.y) +
WiredHome 78:faf49c381591 383 tpMatrix.Cn
WiredHome 78:faf49c381591 384 ) / tpMatrix.Divider ;
WiredHome 78:faf49c381591 385
WiredHome 78:faf49c381591 386 TouchPoint->y = ( (tpMatrix.Dn * screenpoint.x) +
WiredHome 78:faf49c381591 387 (tpMatrix.En * screenpoint.y) +
WiredHome 78:faf49c381591 388 tpMatrix.Fn
WiredHome 78:faf49c381591 389 ) / tpMatrix.Divider ;
WiredHome 78:faf49c381591 390 } else {
WiredHome 78:faf49c381591 391 retValue = bad_parameter ;
WiredHome 78:faf49c381591 392 }
WiredHome 78:faf49c381591 393 }
WiredHome 78:faf49c381591 394 return( retValue );
WiredHome 78:faf49c381591 395 }
WiredHome 78:faf49c381591 396
WiredHome 78:faf49c381591 397
WiredHome 78:faf49c381591 398 RetCode_t RA8875::TouchPanelSetMatrix(tpMatrix_t * matrixPtr)
WiredHome 78:faf49c381591 399 {
WiredHome 78:faf49c381591 400 if (matrixPtr == NULL || matrixPtr->Divider == 0)
WiredHome 78:faf49c381591 401 return bad_parameter;
WiredHome 78:faf49c381591 402 memcpy(&tpMatrix, matrixPtr, sizeof(tpMatrix_t));
WiredHome 78:faf49c381591 403 return noerror;
WiredHome 78:faf49c381591 404 }
WiredHome 78:faf49c381591 405
WiredHome 78:faf49c381591 406 // #### end of touch panel code additions