Peter Drescher
The wait in mci_WaitForEvent will delay all card transactions.
Fork of
EALib
by 
EmbeddedArtists AB
TSC2046.cpp@0:0fdadbc3d852, 2013-09-26 (annotated)
- Committer:
- embeddedartists
- Date:
- Thu Sep 26 06:37:02 2013 +0000
- Revision:
- 0:0fdadbc3d852
- Child:
- 4:b32cf4ef45c5
First version
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| embeddedartists | 0:0fdadbc3d852 | 1 | |
| embeddedartists | 0:0fdadbc3d852 | 2 | #include "mbed.h" |
| embeddedartists | 0:0fdadbc3d852 | 3 | #include "TSC2046.h" |
| embeddedartists | 0:0fdadbc3d852 | 4 | |
| embeddedartists | 0:0fdadbc3d852 | 5 | #ifndef ABS |
| embeddedartists | 0:0fdadbc3d852 | 6 | #define ABS(x) ( ((int32_t)(x)) < 0 ? (-(x)) : (x)) |
| embeddedartists | 0:0fdadbc3d852 | 7 | #endif |
| embeddedartists | 0:0fdadbc3d852 | 8 | |
| embeddedartists | 0:0fdadbc3d852 | 9 | #define ADS_START (1 << 7) |
| embeddedartists | 0:0fdadbc3d852 | 10 | #define ADS_A2A1A0_d_y (1 << 4) /* differential */ |
| embeddedartists | 0:0fdadbc3d852 | 11 | #define ADS_A2A1A0_d_z1 (3 << 4) /* differential */ |
| embeddedartists | 0:0fdadbc3d852 | 12 | #define ADS_A2A1A0_d_z2 (4 << 4) /* differential */ |
| embeddedartists | 0:0fdadbc3d852 | 13 | #define ADS_A2A1A0_d_x (5 << 4) /* differential */ |
| embeddedartists | 0:0fdadbc3d852 | 14 | #define ADS_A2A1A0_temp0 (0 << 4) /* non-differential */ |
| embeddedartists | 0:0fdadbc3d852 | 15 | #define ADS_A2A1A0_vbatt (2 << 4) /* non-differential */ |
| embeddedartists | 0:0fdadbc3d852 | 16 | #define ADS_A2A1A0_vaux (6 << 4) /* non-differential */ |
| embeddedartists | 0:0fdadbc3d852 | 17 | #define ADS_A2A1A0_temp1 (7 << 4) /* non-differential */ |
| embeddedartists | 0:0fdadbc3d852 | 18 | #define ADS_8_BIT (1 << 3) |
| embeddedartists | 0:0fdadbc3d852 | 19 | #define ADS_12_BIT (0 << 3) |
| embeddedartists | 0:0fdadbc3d852 | 20 | #define ADS_SER (1 << 2) /* non-differential */ |
| embeddedartists | 0:0fdadbc3d852 | 21 | #define ADS_DFR (0 << 2) /* differential */ |
| embeddedartists | 0:0fdadbc3d852 | 22 | #define ADS_PD10_PDOWN (0 << 0) /* lowpower mode + penirq */ |
| embeddedartists | 0:0fdadbc3d852 | 23 | #define ADS_PD10_ADC_ON (1 << 0) /* ADC on */ |
| embeddedartists | 0:0fdadbc3d852 | 24 | #define ADS_PD10_REF_ON (2 << 0) /* vREF on + penirq */ |
| embeddedartists | 0:0fdadbc3d852 | 25 | #define ADS_PD10_ALL_ON (3 << 0) /* ADC + vREF on */ |
| embeddedartists | 0:0fdadbc3d852 | 26 | |
| embeddedartists | 0:0fdadbc3d852 | 27 | |
| embeddedartists | 0:0fdadbc3d852 | 28 | #define READ_12BIT_DFR(d, adc, vref) (ADS_START | d \ |
| embeddedartists | 0:0fdadbc3d852 | 29 | | ADS_12_BIT | ADS_DFR | \ |
| embeddedartists | 0:0fdadbc3d852 | 30 | (adc ? ADS_PD10_ADC_ON : 0) | (vref ? ADS_PD10_REF_ON : 0)) |
| embeddedartists | 0:0fdadbc3d852 | 31 | |
| embeddedartists | 0:0fdadbc3d852 | 32 | #define READ_Y(vref) (READ_12BIT_DFR(ADS_A2A1A0_d_y, 1, vref)) |
| embeddedartists | 0:0fdadbc3d852 | 33 | #define READ_Z1(vref) (READ_12BIT_DFR(ADS_A2A1A0_d_z1, 1, vref)) |
| embeddedartists | 0:0fdadbc3d852 | 34 | #define READ_Z2(vref) (READ_12BIT_DFR(ADS_A2A1A0_d_z2, 1, vref)) |
| embeddedartists | 0:0fdadbc3d852 | 35 | #define READ_X(vref) (READ_12BIT_DFR(ADS_A2A1A0_d_x, 1, vref)) |
| embeddedartists | 0:0fdadbc3d852 | 36 | #define PWRDOWN (READ_12BIT_DFR(ADS_A2A1A0_d_y, 0, 0)) /* LAST */ |
| embeddedartists | 0:0fdadbc3d852 | 37 | |
| embeddedartists | 0:0fdadbc3d852 | 38 | /* single-ended samples need to first power up reference voltage; |
| embeddedartists | 0:0fdadbc3d852 | 39 | * we leave both ADC and VREF powered |
| embeddedartists | 0:0fdadbc3d852 | 40 | */ |
| embeddedartists | 0:0fdadbc3d852 | 41 | #define READ_12BIT_SER(x) (ADS_START | x \ |
| embeddedartists | 0:0fdadbc3d852 | 42 | | ADS_12_BIT | ADS_SER) |
| embeddedartists | 0:0fdadbc3d852 | 43 | |
| embeddedartists | 0:0fdadbc3d852 | 44 | #define REF_ON (READ_12BIT_DFR(ADS_A2A1A0_d_x, 1, 1)) |
| embeddedartists | 0:0fdadbc3d852 | 45 | #define REF_OFF (READ_12BIT_DFR(ADS_A2A1A0_d_y, 0, 0)) |
| embeddedartists | 0:0fdadbc3d852 | 46 | |
| embeddedartists | 0:0fdadbc3d852 | 47 | #define DEBOUNCE_MAX 10 |
| embeddedartists | 0:0fdadbc3d852 | 48 | #define DEBOUNCE_TOL 3 |
| embeddedartists | 0:0fdadbc3d852 | 49 | |
| embeddedartists | 0:0fdadbc3d852 | 50 | TSC2046::TSC2046(PinName mosi, PinName miso, PinName sck, PinName cs) : |
| embeddedartists | 0:0fdadbc3d852 | 51 | _spi(mosi, miso, sck), _cs(cs) |
| embeddedartists | 0:0fdadbc3d852 | 52 | { |
| embeddedartists | 0:0fdadbc3d852 | 53 | _cs = 1; // active low |
| embeddedartists | 0:0fdadbc3d852 | 54 | |
| embeddedartists | 0:0fdadbc3d852 | 55 | _spi.format(8, 3); |
| embeddedartists | 0:0fdadbc3d852 | 56 | _spi.frequency(1500000); |
| embeddedartists | 0:0fdadbc3d852 | 57 | _calibrated = false; |
| embeddedartists | 0:0fdadbc3d852 | 58 | _initialized = false; |
| embeddedartists | 0:0fdadbc3d852 | 59 | } |
| embeddedartists | 0:0fdadbc3d852 | 60 | |
| embeddedartists | 0:0fdadbc3d852 | 61 | |
| embeddedartists | 0:0fdadbc3d852 | 62 | void TSC2046::read(touchCoordinate_t &coord) { |
| embeddedartists | 0:0fdadbc3d852 | 63 | |
| embeddedartists | 0:0fdadbc3d852 | 64 | touchCoordinate_t tmpCoord; |
| embeddedartists | 0:0fdadbc3d852 | 65 | calibPoint_t displayPoint; |
| embeddedartists | 0:0fdadbc3d852 | 66 | calibPoint_t screenSample; |
| embeddedartists | 0:0fdadbc3d852 | 67 | |
| embeddedartists | 0:0fdadbc3d852 | 68 | if (!_initialized) { |
| embeddedartists | 0:0fdadbc3d852 | 69 | init(); |
| embeddedartists | 0:0fdadbc3d852 | 70 | _initialized = true; |
| embeddedartists | 0:0fdadbc3d852 | 71 | } |
| embeddedartists | 0:0fdadbc3d852 | 72 | |
| embeddedartists | 0:0fdadbc3d852 | 73 | readAndFilter(tmpCoord); |
| embeddedartists | 0:0fdadbc3d852 | 74 | |
| embeddedartists | 0:0fdadbc3d852 | 75 | _cs = 0; |
| embeddedartists | 0:0fdadbc3d852 | 76 | _spi.write(PWRDOWN); |
| embeddedartists | 0:0fdadbc3d852 | 77 | _cs = 1; |
| embeddedartists | 0:0fdadbc3d852 | 78 | |
| embeddedartists | 0:0fdadbc3d852 | 79 | coord.z = tmpCoord.z; |
| embeddedartists | 0:0fdadbc3d852 | 80 | |
| embeddedartists | 0:0fdadbc3d852 | 81 | if (_calibrated) { |
| embeddedartists | 0:0fdadbc3d852 | 82 | screenSample.x = tmpCoord.x; |
| embeddedartists | 0:0fdadbc3d852 | 83 | screenSample.y = tmpCoord.y; |
| embeddedartists | 0:0fdadbc3d852 | 84 | |
| embeddedartists | 0:0fdadbc3d852 | 85 | getDisplayPoint(&displayPoint, &screenSample, &_calibMatrix); |
| embeddedartists | 0:0fdadbc3d852 | 86 | |
| embeddedartists | 0:0fdadbc3d852 | 87 | coord.x = displayPoint.x; |
| embeddedartists | 0:0fdadbc3d852 | 88 | coord.y = displayPoint.y; |
| embeddedartists | 0:0fdadbc3d852 | 89 | } |
| embeddedartists | 0:0fdadbc3d852 | 90 | else { |
| embeddedartists | 0:0fdadbc3d852 | 91 | coord.x = tmpCoord.x; |
| embeddedartists | 0:0fdadbc3d852 | 92 | coord.y = tmpCoord.y; |
| embeddedartists | 0:0fdadbc3d852 | 93 | } |
| embeddedartists | 0:0fdadbc3d852 | 94 | |
| embeddedartists | 0:0fdadbc3d852 | 95 | } |
| embeddedartists | 0:0fdadbc3d852 | 96 | |
| embeddedartists | 0:0fdadbc3d852 | 97 | void TSC2046::calibrate(touchCoordinate_t &ref1, |
| embeddedartists | 0:0fdadbc3d852 | 98 | touchCoordinate_t &ref2, |
| embeddedartists | 0:0fdadbc3d852 | 99 | touchCoordinate_t &ref3, |
| embeddedartists | 0:0fdadbc3d852 | 100 | touchCoordinate_t &scr1, |
| embeddedartists | 0:0fdadbc3d852 | 101 | touchCoordinate_t &scr2, |
| embeddedartists | 0:0fdadbc3d852 | 102 | touchCoordinate_t &scr3) { |
| embeddedartists | 0:0fdadbc3d852 | 103 | |
| embeddedartists | 0:0fdadbc3d852 | 104 | calibPoint_t disp[3]; |
| embeddedartists | 0:0fdadbc3d852 | 105 | calibPoint_t scr[3]; |
| embeddedartists | 0:0fdadbc3d852 | 106 | |
| embeddedartists | 0:0fdadbc3d852 | 107 | disp[0].x = ref1.x; |
| embeddedartists | 0:0fdadbc3d852 | 108 | disp[0].y = ref1.y; |
| embeddedartists | 0:0fdadbc3d852 | 109 | disp[1].x = ref2.x; |
| embeddedartists | 0:0fdadbc3d852 | 110 | disp[1].y = ref2.y; |
| embeddedartists | 0:0fdadbc3d852 | 111 | disp[2].x = ref3.x; |
| embeddedartists | 0:0fdadbc3d852 | 112 | disp[2].y = ref3.y; |
| embeddedartists | 0:0fdadbc3d852 | 113 | |
| embeddedartists | 0:0fdadbc3d852 | 114 | scr[0].x = scr1.x; |
| embeddedartists | 0:0fdadbc3d852 | 115 | scr[0].y = scr1.y; |
| embeddedartists | 0:0fdadbc3d852 | 116 | scr[1].x = scr2.x; |
| embeddedartists | 0:0fdadbc3d852 | 117 | scr[1].y = scr2.y; |
| embeddedartists | 0:0fdadbc3d852 | 118 | scr[2].x = scr3.x; |
| embeddedartists | 0:0fdadbc3d852 | 119 | scr[2].y = scr3.y; |
| embeddedartists | 0:0fdadbc3d852 | 120 | |
| embeddedartists | 0:0fdadbc3d852 | 121 | setCalibrationMatrix(disp, scr, &_calibMatrix); |
| embeddedartists | 0:0fdadbc3d852 | 122 | |
| embeddedartists | 0:0fdadbc3d852 | 123 | _calibrated = true; |
| embeddedartists | 0:0fdadbc3d852 | 124 | |
| embeddedartists | 0:0fdadbc3d852 | 125 | } |
| embeddedartists | 0:0fdadbc3d852 | 126 | |
| embeddedartists | 0:0fdadbc3d852 | 127 | void TSC2046::uncalibrate() { |
| embeddedartists | 0:0fdadbc3d852 | 128 | _calibrated = false; |
| embeddedartists | 0:0fdadbc3d852 | 129 | } |
| embeddedartists | 0:0fdadbc3d852 | 130 | |
| embeddedartists | 0:0fdadbc3d852 | 131 | |
| embeddedartists | 0:0fdadbc3d852 | 132 | void TSC2046::init() { |
| embeddedartists | 0:0fdadbc3d852 | 133 | |
| embeddedartists | 0:0fdadbc3d852 | 134 | _cs = 0; |
| embeddedartists | 0:0fdadbc3d852 | 135 | |
| embeddedartists | 0:0fdadbc3d852 | 136 | _spi.write(REF_ON); |
| embeddedartists | 0:0fdadbc3d852 | 137 | _spi.write((READ_12BIT_SER(ADS_A2A1A0_vaux) | ADS_PD10_ALL_ON)); |
| embeddedartists | 0:0fdadbc3d852 | 138 | _spi.write(PWRDOWN); |
| embeddedartists | 0:0fdadbc3d852 | 139 | |
| embeddedartists | 0:0fdadbc3d852 | 140 | _cs = 1; |
| embeddedartists | 0:0fdadbc3d852 | 141 | } |
| embeddedartists | 0:0fdadbc3d852 | 142 | |
| embeddedartists | 0:0fdadbc3d852 | 143 | void TSC2046::readAndFilter(touchCoordinate_t &coord) |
| embeddedartists | 0:0fdadbc3d852 | 144 | { |
| embeddedartists | 0:0fdadbc3d852 | 145 | int32_t ix, iy, iz1, iz2 = 0; |
| embeddedartists | 0:0fdadbc3d852 | 146 | int32_t lastx, lasty, lastz1, lastz2 = 0; |
| embeddedartists | 0:0fdadbc3d852 | 147 | int i = 0; |
| embeddedartists | 0:0fdadbc3d852 | 148 | |
| embeddedartists | 0:0fdadbc3d852 | 149 | coord.x = 0; |
| embeddedartists | 0:0fdadbc3d852 | 150 | coord.y = 0; |
| embeddedartists | 0:0fdadbc3d852 | 151 | coord.z = 0; |
| embeddedartists | 0:0fdadbc3d852 | 152 | |
| embeddedartists | 0:0fdadbc3d852 | 153 | lasty = getFilteredValue(READ_Y(0)); |
| embeddedartists | 0:0fdadbc3d852 | 154 | lasty >>= 3; |
| embeddedartists | 0:0fdadbc3d852 | 155 | if (lasty >= 4095) { |
| embeddedartists | 0:0fdadbc3d852 | 156 | lasty = 0; |
| embeddedartists | 0:0fdadbc3d852 | 157 | } |
| embeddedartists | 0:0fdadbc3d852 | 158 | |
| embeddedartists | 0:0fdadbc3d852 | 159 | lastx = getFilteredValue(READ_X(0)); |
| embeddedartists | 0:0fdadbc3d852 | 160 | lastx >>= 3; |
| embeddedartists | 0:0fdadbc3d852 | 161 | if (lastx >= 4095) { |
| embeddedartists | 0:0fdadbc3d852 | 162 | lastx = 0; |
| embeddedartists | 0:0fdadbc3d852 | 163 | } |
| embeddedartists | 0:0fdadbc3d852 | 164 | |
| embeddedartists | 0:0fdadbc3d852 | 165 | lastz1 = getFilteredValue(READ_Z1(0)); |
| embeddedartists | 0:0fdadbc3d852 | 166 | lastz1 >>= 3; |
| embeddedartists | 0:0fdadbc3d852 | 167 | |
| embeddedartists | 0:0fdadbc3d852 | 168 | lastz2 = getFilteredValue(READ_Z2(0)); |
| embeddedartists | 0:0fdadbc3d852 | 169 | lastz2 >>= 3; |
| embeddedartists | 0:0fdadbc3d852 | 170 | |
| embeddedartists | 0:0fdadbc3d852 | 171 | |
| embeddedartists | 0:0fdadbc3d852 | 172 | if (lastx && lastz1) { |
| embeddedartists | 0:0fdadbc3d852 | 173 | coord.z = (lastx * ABS(lastz2 - lastz1)) / lastz1; |
| embeddedartists | 0:0fdadbc3d852 | 174 | } |
| embeddedartists | 0:0fdadbc3d852 | 175 | else { |
| embeddedartists | 0:0fdadbc3d852 | 176 | coord.z = 0; |
| embeddedartists | 0:0fdadbc3d852 | 177 | } |
| embeddedartists | 0:0fdadbc3d852 | 178 | |
| embeddedartists | 0:0fdadbc3d852 | 179 | if (coord.z > 20000) { |
| embeddedartists | 0:0fdadbc3d852 | 180 | coord.z = 0; |
| embeddedartists | 0:0fdadbc3d852 | 181 | } |
| embeddedartists | 0:0fdadbc3d852 | 182 | |
| embeddedartists | 0:0fdadbc3d852 | 183 | if (coord.z == 0) { |
| embeddedartists | 0:0fdadbc3d852 | 184 | return; |
| embeddedartists | 0:0fdadbc3d852 | 185 | } |
| embeddedartists | 0:0fdadbc3d852 | 186 | |
| embeddedartists | 0:0fdadbc3d852 | 187 | for (i = 0; i < DEBOUNCE_MAX; i++) { |
| embeddedartists | 0:0fdadbc3d852 | 188 | iy = getFilteredValue(READ_Y(0)); |
| embeddedartists | 0:0fdadbc3d852 | 189 | iy >>= 3; |
| embeddedartists | 0:0fdadbc3d852 | 190 | |
| embeddedartists | 0:0fdadbc3d852 | 191 | if (ABS (lasty - iy) <= DEBOUNCE_TOL) { |
| embeddedartists | 0:0fdadbc3d852 | 192 | break; |
| embeddedartists | 0:0fdadbc3d852 | 193 | } |
| embeddedartists | 0:0fdadbc3d852 | 194 | |
| embeddedartists | 0:0fdadbc3d852 | 195 | lasty = iy; |
| embeddedartists | 0:0fdadbc3d852 | 196 | } |
| embeddedartists | 0:0fdadbc3d852 | 197 | |
| embeddedartists | 0:0fdadbc3d852 | 198 | for (i = 0; i < DEBOUNCE_MAX; i++) { |
| embeddedartists | 0:0fdadbc3d852 | 199 | ix = getFilteredValue(READ_X(0)); |
| embeddedartists | 0:0fdadbc3d852 | 200 | ix >>= 3; |
| embeddedartists | 0:0fdadbc3d852 | 201 | if (ix > 4095) { |
| embeddedartists | 0:0fdadbc3d852 | 202 | ix = 0; |
| embeddedartists | 0:0fdadbc3d852 | 203 | } |
| embeddedartists | 0:0fdadbc3d852 | 204 | |
| embeddedartists | 0:0fdadbc3d852 | 205 | if (ABS (lastx - ix) <= DEBOUNCE_TOL) { |
| embeddedartists | 0:0fdadbc3d852 | 206 | break; |
| embeddedartists | 0:0fdadbc3d852 | 207 | } |
| embeddedartists | 0:0fdadbc3d852 | 208 | |
| embeddedartists | 0:0fdadbc3d852 | 209 | lastx = ix; |
| embeddedartists | 0:0fdadbc3d852 | 210 | } |
| embeddedartists | 0:0fdadbc3d852 | 211 | |
| embeddedartists | 0:0fdadbc3d852 | 212 | for (i = 0; i < DEBOUNCE_MAX; i++) { |
| embeddedartists | 0:0fdadbc3d852 | 213 | iz1 = getFilteredValue(READ_Z1(0)); |
| embeddedartists | 0:0fdadbc3d852 | 214 | iz1 >>= 3; |
| embeddedartists | 0:0fdadbc3d852 | 215 | |
| embeddedartists | 0:0fdadbc3d852 | 216 | if (ABS (lastz1 - iz1) <= DEBOUNCE_TOL) { |
| embeddedartists | 0:0fdadbc3d852 | 217 | break; |
| embeddedartists | 0:0fdadbc3d852 | 218 | } |
| embeddedartists | 0:0fdadbc3d852 | 219 | |
| embeddedartists | 0:0fdadbc3d852 | 220 | lastz1 = iz1; |
| embeddedartists | 0:0fdadbc3d852 | 221 | } |
| embeddedartists | 0:0fdadbc3d852 | 222 | |
| embeddedartists | 0:0fdadbc3d852 | 223 | for (i = 0; i < DEBOUNCE_MAX; i++) { |
| embeddedartists | 0:0fdadbc3d852 | 224 | iz2 = getFilteredValue(READ_Z2(0)); |
| embeddedartists | 0:0fdadbc3d852 | 225 | iz2 >>= 3; |
| embeddedartists | 0:0fdadbc3d852 | 226 | |
| embeddedartists | 0:0fdadbc3d852 | 227 | if (ABS (lastz2 - iz2) <= DEBOUNCE_TOL) { |
| embeddedartists | 0:0fdadbc3d852 | 228 | break; |
| embeddedartists | 0:0fdadbc3d852 | 229 | } |
| embeddedartists | 0:0fdadbc3d852 | 230 | |
| embeddedartists | 0:0fdadbc3d852 | 231 | lastz2 = iz2; |
| embeddedartists | 0:0fdadbc3d852 | 232 | } |
| embeddedartists | 0:0fdadbc3d852 | 233 | |
| embeddedartists | 0:0fdadbc3d852 | 234 | coord.x = ix; |
| embeddedartists | 0:0fdadbc3d852 | 235 | coord.y = iy; |
| embeddedartists | 0:0fdadbc3d852 | 236 | |
| embeddedartists | 0:0fdadbc3d852 | 237 | if (ix && iz1) { |
| embeddedartists | 0:0fdadbc3d852 | 238 | coord.z = (ix * ABS(iz2 - iz1)) / iz1; |
| embeddedartists | 0:0fdadbc3d852 | 239 | } |
| embeddedartists | 0:0fdadbc3d852 | 240 | else { |
| embeddedartists | 0:0fdadbc3d852 | 241 | coord.z = 0; |
| embeddedartists | 0:0fdadbc3d852 | 242 | } |
| embeddedartists | 0:0fdadbc3d852 | 243 | |
| embeddedartists | 0:0fdadbc3d852 | 244 | if (coord.z > 20000) { |
| embeddedartists | 0:0fdadbc3d852 | 245 | coord.z = 0; |
| embeddedartists | 0:0fdadbc3d852 | 246 | } |
| embeddedartists | 0:0fdadbc3d852 | 247 | |
| embeddedartists | 0:0fdadbc3d852 | 248 | } |
| embeddedartists | 0:0fdadbc3d852 | 249 | |
| embeddedartists | 0:0fdadbc3d852 | 250 | int32_t TSC2046::getFilteredValue(int cmd) |
| embeddedartists | 0:0fdadbc3d852 | 251 | { |
| embeddedartists | 0:0fdadbc3d852 | 252 | int32_t a[7]; |
| embeddedartists | 0:0fdadbc3d852 | 253 | int32_t tmp = 0; |
| embeddedartists | 0:0fdadbc3d852 | 254 | int i = 0, j = 0; |
| embeddedartists | 0:0fdadbc3d852 | 255 | |
| embeddedartists | 0:0fdadbc3d852 | 256 | /* |
| embeddedartists | 0:0fdadbc3d852 | 257 | * Median and averaging filter |
| embeddedartists | 0:0fdadbc3d852 | 258 | * |
| embeddedartists | 0:0fdadbc3d852 | 259 | * 1. Get 7 values |
| embeddedartists | 0:0fdadbc3d852 | 260 | * 2. Sort these values |
| embeddedartists | 0:0fdadbc3d852 | 261 | * 3. Take average of the 3 values in the middle |
| embeddedartists | 0:0fdadbc3d852 | 262 | */ |
| embeddedartists | 0:0fdadbc3d852 | 263 | |
| embeddedartists | 0:0fdadbc3d852 | 264 | for (i = 0; i < 7; i++) { |
| embeddedartists | 0:0fdadbc3d852 | 265 | a[i] = spiTransfer(cmd); |
| embeddedartists | 0:0fdadbc3d852 | 266 | } |
| embeddedartists | 0:0fdadbc3d852 | 267 | |
| embeddedartists | 0:0fdadbc3d852 | 268 | // bubble sort |
| embeddedartists | 0:0fdadbc3d852 | 269 | for (i = 0; i < 7; i++) { |
| embeddedartists | 0:0fdadbc3d852 | 270 | for (j = 0; j < (7-(i+1)); j++) { |
| embeddedartists | 0:0fdadbc3d852 | 271 | if (a[j] > a[j+1]) { |
| embeddedartists | 0:0fdadbc3d852 | 272 | // swap |
| embeddedartists | 0:0fdadbc3d852 | 273 | tmp = a[j]; |
| embeddedartists | 0:0fdadbc3d852 | 274 | a[j] = a[j+1]; |
| embeddedartists | 0:0fdadbc3d852 | 275 | a[j+1] = tmp; |
| embeddedartists | 0:0fdadbc3d852 | 276 | } |
| embeddedartists | 0:0fdadbc3d852 | 277 | } |
| embeddedartists | 0:0fdadbc3d852 | 278 | } |
| embeddedartists | 0:0fdadbc3d852 | 279 | |
| embeddedartists | 0:0fdadbc3d852 | 280 | // average of 3 values in the middle |
| embeddedartists | 0:0fdadbc3d852 | 281 | return ((a[2]+a[3]+a[4])/3); |
| embeddedartists | 0:0fdadbc3d852 | 282 | } |
| embeddedartists | 0:0fdadbc3d852 | 283 | |
| embeddedartists | 0:0fdadbc3d852 | 284 | uint16_t TSC2046::spiTransfer(uint8_t cmd) |
| embeddedartists | 0:0fdadbc3d852 | 285 | { |
| embeddedartists | 0:0fdadbc3d852 | 286 | uint8_t data[3]; |
| embeddedartists | 0:0fdadbc3d852 | 287 | |
| embeddedartists | 0:0fdadbc3d852 | 288 | _cs = 0; |
| embeddedartists | 0:0fdadbc3d852 | 289 | |
| embeddedartists | 0:0fdadbc3d852 | 290 | /*data[0] = */_spi.write(cmd); |
| embeddedartists | 0:0fdadbc3d852 | 291 | data[0] = _spi.write(0xff); |
| embeddedartists | 0:0fdadbc3d852 | 292 | data[1] = _spi.write(0xff); |
| embeddedartists | 0:0fdadbc3d852 | 293 | |
| embeddedartists | 0:0fdadbc3d852 | 294 | _cs = 1; |
| embeddedartists | 0:0fdadbc3d852 | 295 | |
| embeddedartists | 0:0fdadbc3d852 | 296 | return ((data[0] << 8) | data[1]); |
| embeddedartists | 0:0fdadbc3d852 | 297 | } |
| embeddedartists | 0:0fdadbc3d852 | 298 | |
| embeddedartists | 0:0fdadbc3d852 | 299 | |
| embeddedartists | 0:0fdadbc3d852 | 300 | // ############################################################################ |
| embeddedartists | 0:0fdadbc3d852 | 301 | // >>>>>>>> Calibrate code >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> |
| embeddedartists | 0:0fdadbc3d852 | 302 | // ############################################################################ |
| embeddedartists | 0:0fdadbc3d852 | 303 | |
| embeddedartists | 0:0fdadbc3d852 | 304 | |
| embeddedartists | 0:0fdadbc3d852 | 305 | /* |
| embeddedartists | 0:0fdadbc3d852 | 306 | * |
| embeddedartists | 0:0fdadbc3d852 | 307 | * Copyright (c) 2001, Carlos E. Vidales. All rights reserved. |
| embeddedartists | 0:0fdadbc3d852 | 308 | * |
| embeddedartists | 0:0fdadbc3d852 | 309 | * This sample program was written and put in the public domain |
| embeddedartists | 0:0fdadbc3d852 | 310 | * by Carlos E. Vidales. The program is provided "as is" |
| embeddedartists | 0:0fdadbc3d852 | 311 | * without warranty of any kind, either expressed or implied. |
| embeddedartists | 0:0fdadbc3d852 | 312 | * If you choose to use the program within your own products |
| embeddedartists | 0:0fdadbc3d852 | 313 | * you do so at your own risk, and assume the responsibility |
| embeddedartists | 0:0fdadbc3d852 | 314 | * for servicing, repairing or correcting the program should |
| embeddedartists | 0:0fdadbc3d852 | 315 | * it prove defective in any manner. |
| embeddedartists | 0:0fdadbc3d852 | 316 | * You may copy and distribute the program's source code in any |
| embeddedartists | 0:0fdadbc3d852 | 317 | * medium, provided that you also include in each copy an |
| embeddedartists | 0:0fdadbc3d852 | 318 | * appropriate copyright notice and disclaimer of warranty. |
| embeddedartists | 0:0fdadbc3d852 | 319 | * You may also modify this program and distribute copies of |
| embeddedartists | 0:0fdadbc3d852 | 320 | * it provided that you include prominent notices stating |
| embeddedartists | 0:0fdadbc3d852 | 321 | * that you changed the file(s) and the date of any change, |
| embeddedartists | 0:0fdadbc3d852 | 322 | * and that you do not charge any royalties or licenses for |
| embeddedartists | 0:0fdadbc3d852 | 323 | * its use. |
| embeddedartists | 0:0fdadbc3d852 | 324 | * |
| embeddedartists | 0:0fdadbc3d852 | 325 | * |
| embeddedartists | 0:0fdadbc3d852 | 326 | * |
| embeddedartists | 0:0fdadbc3d852 | 327 | * File Name: calibrate.c |
| embeddedartists | 0:0fdadbc3d852 | 328 | * |
| embeddedartists | 0:0fdadbc3d852 | 329 | * |
| embeddedartists | 0:0fdadbc3d852 | 330 | * This file contains functions that implement calculations |
| embeddedartists | 0:0fdadbc3d852 | 331 | * necessary to obtain calibration factors for a touch screen |
| embeddedartists | 0:0fdadbc3d852 | 332 | * that suffers from multiple distortion effects: namely, |
| embeddedartists | 0:0fdadbc3d852 | 333 | * translation, scaling and rotation. |
| embeddedartists | 0:0fdadbc3d852 | 334 | * |
| embeddedartists | 0:0fdadbc3d852 | 335 | * The following set of equations represent a valid display |
| embeddedartists | 0:0fdadbc3d852 | 336 | * point given a corresponding set of touch screen points: |
| embeddedartists | 0:0fdadbc3d852 | 337 | * |
| embeddedartists | 0:0fdadbc3d852 | 338 | * |
| embeddedartists | 0:0fdadbc3d852 | 339 | * /- -\ |
| embeddedartists | 0:0fdadbc3d852 | 340 | * /- -\ /- -\ | | |
| embeddedartists | 0:0fdadbc3d852 | 341 | * | | | | | Xs | |
| embeddedartists | 0:0fdadbc3d852 | 342 | * | Xd | | A B C | | | |
| embeddedartists | 0:0fdadbc3d852 | 343 | * | | = | | * | Ys | |
| embeddedartists | 0:0fdadbc3d852 | 344 | * | Yd | | D E F | | | |
| embeddedartists | 0:0fdadbc3d852 | 345 | * | | | | | 1 | |
| embeddedartists | 0:0fdadbc3d852 | 346 | * \- -/ \- -/ | | |
| embeddedartists | 0:0fdadbc3d852 | 347 | * \- -/ |
| embeddedartists | 0:0fdadbc3d852 | 348 | * |
| embeddedartists | 0:0fdadbc3d852 | 349 | * |
| embeddedartists | 0:0fdadbc3d852 | 350 | * where: |
| embeddedartists | 0:0fdadbc3d852 | 351 | * |
| embeddedartists | 0:0fdadbc3d852 | 352 | * (Xd,Yd) represents the desired display point |
| embeddedartists | 0:0fdadbc3d852 | 353 | * coordinates, |
| embeddedartists | 0:0fdadbc3d852 | 354 | * |
| embeddedartists | 0:0fdadbc3d852 | 355 | * (Xs,Ys) represents the available touch screen |
| embeddedartists | 0:0fdadbc3d852 | 356 | * coordinates, and the matrix |
| embeddedartists | 0:0fdadbc3d852 | 357 | * |
| embeddedartists | 0:0fdadbc3d852 | 358 | * /- -\ |
| embeddedartists | 0:0fdadbc3d852 | 359 | * |A,B,C| |
| embeddedartists | 0:0fdadbc3d852 | 360 | * |D,E,F| represents the factors used to translate |
| embeddedartists | 0:0fdadbc3d852 | 361 | * \- -/ the available touch screen point values |
| embeddedartists | 0:0fdadbc3d852 | 362 | * into the corresponding display |
| embeddedartists | 0:0fdadbc3d852 | 363 | * coordinates. |
| embeddedartists | 0:0fdadbc3d852 | 364 | * |
| embeddedartists | 0:0fdadbc3d852 | 365 | * |
| embeddedartists | 0:0fdadbc3d852 | 366 | * Note that for practical considerations, the utilitities |
| embeddedartists | 0:0fdadbc3d852 | 367 | * within this file do not use the matrix coefficients as |
| embeddedartists | 0:0fdadbc3d852 | 368 | * defined above, but instead use the following |
| embeddedartists | 0:0fdadbc3d852 | 369 | * equivalents, since floating point math is not used: |
| embeddedartists | 0:0fdadbc3d852 | 370 | * |
| embeddedartists | 0:0fdadbc3d852 | 371 | * A = An/Divider |
| embeddedartists | 0:0fdadbc3d852 | 372 | * B = Bn/Divider |
| embeddedartists | 0:0fdadbc3d852 | 373 | * C = Cn/Divider |
| embeddedartists | 0:0fdadbc3d852 | 374 | * D = Dn/Divider |
| embeddedartists | 0:0fdadbc3d852 | 375 | * E = En/Divider |
| embeddedartists | 0:0fdadbc3d852 | 376 | * F = Fn/Divider |
| embeddedartists | 0:0fdadbc3d852 | 377 | * |
| embeddedartists | 0:0fdadbc3d852 | 378 | * |
| embeddedartists | 0:0fdadbc3d852 | 379 | * |
| embeddedartists | 0:0fdadbc3d852 | 380 | * The functions provided within this file are: |
| embeddedartists | 0:0fdadbc3d852 | 381 | * |
| embeddedartists | 0:0fdadbc3d852 | 382 | * setCalibrationMatrix() - calculates the set of factors |
| embeddedartists | 0:0fdadbc3d852 | 383 | * in the above equation, given |
| embeddedartists | 0:0fdadbc3d852 | 384 | * three sets of test points. |
| embeddedartists | 0:0fdadbc3d852 | 385 | * getDisplayPoint() - returns the actual display |
| embeddedartists | 0:0fdadbc3d852 | 386 | * coordinates, given a set of |
| embeddedartists | 0:0fdadbc3d852 | 387 | * touch screen coordinates. |
| embeddedartists | 0:0fdadbc3d852 | 388 | * translateRawScreenCoordinates() - helper function to transform |
| embeddedartists | 0:0fdadbc3d852 | 389 | * raw screen points into values |
| embeddedartists | 0:0fdadbc3d852 | 390 | * scaled to the desired display |
| embeddedartists | 0:0fdadbc3d852 | 391 | * resolution. |
| embeddedartists | 0:0fdadbc3d852 | 392 | * |
| embeddedartists | 0:0fdadbc3d852 | 393 | * |
| embeddedartists | 0:0fdadbc3d852 | 394 | */ |
| embeddedartists | 0:0fdadbc3d852 | 395 | |
| embeddedartists | 0:0fdadbc3d852 | 396 | |
| embeddedartists | 0:0fdadbc3d852 | 397 | /********************************************************************** |
| embeddedartists | 0:0fdadbc3d852 | 398 | * |
| embeddedartists | 0:0fdadbc3d852 | 399 | * Function: setCalibrationMatrix() |
| embeddedartists | 0:0fdadbc3d852 | 400 | * |
| embeddedartists | 0:0fdadbc3d852 | 401 | * Description: Calling this function with valid input data |
| embeddedartists | 0:0fdadbc3d852 | 402 | * in the display and screen input arguments |
| embeddedartists | 0:0fdadbc3d852 | 403 | * causes the calibration factors between the |
| embeddedartists | 0:0fdadbc3d852 | 404 | * screen and display points to be calculated, |
| embeddedartists | 0:0fdadbc3d852 | 405 | * and the output argument - matrixPtr - to be |
| embeddedartists | 0:0fdadbc3d852 | 406 | * populated. |
| embeddedartists | 0:0fdadbc3d852 | 407 | * |
| embeddedartists | 0:0fdadbc3d852 | 408 | * This function needs to be called only when new |
| embeddedartists | 0:0fdadbc3d852 | 409 | * calibration factors are desired. |
| embeddedartists | 0:0fdadbc3d852 | 410 | * |
| embeddedartists | 0:0fdadbc3d852 | 411 | * |
| embeddedartists | 0:0fdadbc3d852 | 412 | * Argument(s): displayPtr (input) - Pointer to an array of three |
| embeddedartists | 0:0fdadbc3d852 | 413 | * sample, reference points. |
| embeddedartists | 0:0fdadbc3d852 | 414 | * screenPtr (input) - Pointer to the array of touch |
| embeddedartists | 0:0fdadbc3d852 | 415 | * screen points corresponding |
| embeddedartists | 0:0fdadbc3d852 | 416 | * to the reference display points. |
| embeddedartists | 0:0fdadbc3d852 | 417 | * matrixPtr (output) - Pointer to the calibration |
| embeddedartists | 0:0fdadbc3d852 | 418 | * matrix computed for the set |
| embeddedartists | 0:0fdadbc3d852 | 419 | * of points being provided. |
| embeddedartists | 0:0fdadbc3d852 | 420 | * |
| embeddedartists | 0:0fdadbc3d852 | 421 | * |
| embeddedartists | 0:0fdadbc3d852 | 422 | * From the article text, recall that the matrix coefficients are |
| embeddedartists | 0:0fdadbc3d852 | 423 | * resolved to be the following: |
| embeddedartists | 0:0fdadbc3d852 | 424 | * |
| embeddedartists | 0:0fdadbc3d852 | 425 | * |
| embeddedartists | 0:0fdadbc3d852 | 426 | * Divider = (Xs0 - Xs2)*(Ys1 - Ys2) - (Xs1 - Xs2)*(Ys0 - Ys2) |
| embeddedartists | 0:0fdadbc3d852 | 427 | * |
| embeddedartists | 0:0fdadbc3d852 | 428 | * |
| embeddedartists | 0:0fdadbc3d852 | 429 | * |
| embeddedartists | 0:0fdadbc3d852 | 430 | * (Xd0 - Xd2)*(Ys1 - Ys2) - (Xd1 - Xd2)*(Ys0 - Ys2) |
| embeddedartists | 0:0fdadbc3d852 | 431 | * A = --------------------------------------------------- |
| embeddedartists | 0:0fdadbc3d852 | 432 | * Divider |
| embeddedartists | 0:0fdadbc3d852 | 433 | * |
| embeddedartists | 0:0fdadbc3d852 | 434 | * |
| embeddedartists | 0:0fdadbc3d852 | 435 | * (Xs0 - Xs2)*(Xd1 - Xd2) - (Xd0 - Xd2)*(Xs1 - Xs2) |
| embeddedartists | 0:0fdadbc3d852 | 436 | * B = --------------------------------------------------- |
| embeddedartists | 0:0fdadbc3d852 | 437 | * Divider |
| embeddedartists | 0:0fdadbc3d852 | 438 | * |
| embeddedartists | 0:0fdadbc3d852 | 439 | * |
| embeddedartists | 0:0fdadbc3d852 | 440 | * Ys0*(Xs2*Xd1 - Xs1*Xd2) + |
| embeddedartists | 0:0fdadbc3d852 | 441 | * Ys1*(Xs0*Xd2 - Xs2*Xd0) + |
| embeddedartists | 0:0fdadbc3d852 | 442 | * Ys2*(Xs1*Xd0 - Xs0*Xd1) |
| embeddedartists | 0:0fdadbc3d852 | 443 | * C = --------------------------------------------------- |
| embeddedartists | 0:0fdadbc3d852 | 444 | * Divider |
| embeddedartists | 0:0fdadbc3d852 | 445 | * |
| embeddedartists | 0:0fdadbc3d852 | 446 | * |
| embeddedartists | 0:0fdadbc3d852 | 447 | * (Yd0 - Yd2)*(Ys1 - Ys2) - (Yd1 - Yd2)*(Ys0 - Ys2) |
| embeddedartists | 0:0fdadbc3d852 | 448 | * D = --------------------------------------------------- |
| embeddedartists | 0:0fdadbc3d852 | 449 | * Divider |
| embeddedartists | 0:0fdadbc3d852 | 450 | * |
| embeddedartists | 0:0fdadbc3d852 | 451 | * |
| embeddedartists | 0:0fdadbc3d852 | 452 | * (Xs0 - Xs2)*(Yd1 - Yd2) - (Yd0 - Yd2)*(Xs1 - Xs2) |
| embeddedartists | 0:0fdadbc3d852 | 453 | * E = --------------------------------------------------- |
| embeddedartists | 0:0fdadbc3d852 | 454 | * Divider |
| embeddedartists | 0:0fdadbc3d852 | 455 | * |
| embeddedartists | 0:0fdadbc3d852 | 456 | * |
| embeddedartists | 0:0fdadbc3d852 | 457 | * Ys0*(Xs2*Yd1 - Xs1*Yd2) + |
| embeddedartists | 0:0fdadbc3d852 | 458 | * Ys1*(Xs0*Yd2 - Xs2*Yd0) + |
| embeddedartists | 0:0fdadbc3d852 | 459 | * Ys2*(Xs1*Yd0 - Xs0*Yd1) |
| embeddedartists | 0:0fdadbc3d852 | 460 | * F = --------------------------------------------------- |
| embeddedartists | 0:0fdadbc3d852 | 461 | * Divider |
| embeddedartists | 0:0fdadbc3d852 | 462 | * |
| embeddedartists | 0:0fdadbc3d852 | 463 | * |
| embeddedartists | 0:0fdadbc3d852 | 464 | * Return: OK - the calibration matrix was correctly |
| embeddedartists | 0:0fdadbc3d852 | 465 | * calculated and its value is in the |
| embeddedartists | 0:0fdadbc3d852 | 466 | * output argument. |
| embeddedartists | 0:0fdadbc3d852 | 467 | * NOT_OK - an error was detected and the |
| embeddedartists | 0:0fdadbc3d852 | 468 | * function failed to return a valid |
| embeddedartists | 0:0fdadbc3d852 | 469 | * set of matrix values. |
| embeddedartists | 0:0fdadbc3d852 | 470 | * The only time this sample code returns |
| embeddedartists | 0:0fdadbc3d852 | 471 | * NOT_OK is when Divider == 0 |
| embeddedartists | 0:0fdadbc3d852 | 472 | * |
| embeddedartists | 0:0fdadbc3d852 | 473 | * |
| embeddedartists | 0:0fdadbc3d852 | 474 | * |
| embeddedartists | 0:0fdadbc3d852 | 475 | * NOTE! NOTE! NOTE! |
| embeddedartists | 0:0fdadbc3d852 | 476 | * |
| embeddedartists | 0:0fdadbc3d852 | 477 | * setCalibrationMatrix() and getDisplayPoint() will do fine |
| embeddedartists | 0:0fdadbc3d852 | 478 | * for you as they are, provided that your digitizer |
| embeddedartists | 0:0fdadbc3d852 | 479 | * resolution does not exceed 10 bits (1024 values). Higher |
| embeddedartists | 0:0fdadbc3d852 | 480 | * resolutions may cause the integer operations to overflow |
| embeddedartists | 0:0fdadbc3d852 | 481 | * and return incorrect values. If you wish to use these |
| embeddedartists | 0:0fdadbc3d852 | 482 | * functions with digitizer resolutions of 12 bits (4096 |
| embeddedartists | 0:0fdadbc3d852 | 483 | * values) you will either have to a) use 64-bit signed |
| embeddedartists | 0:0fdadbc3d852 | 484 | * integer variables and math, or b) judiciously modify the |
| embeddedartists | 0:0fdadbc3d852 | 485 | * operations to scale results by a factor of 2 or even 4. |
| embeddedartists | 0:0fdadbc3d852 | 486 | * |
| embeddedartists | 0:0fdadbc3d852 | 487 | * |
| embeddedartists | 0:0fdadbc3d852 | 488 | */ |
| embeddedartists | 0:0fdadbc3d852 | 489 | int TSC2046::setCalibrationMatrix( calibPoint_t * displayPtr, |
| embeddedartists | 0:0fdadbc3d852 | 490 | calibPoint_t * screenPtr, |
| embeddedartists | 0:0fdadbc3d852 | 491 | calibMatrix_t * matrixPtr) |
| embeddedartists | 0:0fdadbc3d852 | 492 | { |
| embeddedartists | 0:0fdadbc3d852 | 493 | int retValue = 0 ; |
| embeddedartists | 0:0fdadbc3d852 | 494 | |
| embeddedartists | 0:0fdadbc3d852 | 495 | |
| embeddedartists | 0:0fdadbc3d852 | 496 | matrixPtr->Divider = ((screenPtr[0].x - screenPtr[2].x) * (screenPtr[1].y - screenPtr[2].y)) - |
| embeddedartists | 0:0fdadbc3d852 | 497 | ((screenPtr[1].x - screenPtr[2].x) * (screenPtr[0].y - screenPtr[2].y)) ; |
| embeddedartists | 0:0fdadbc3d852 | 498 | if( matrixPtr->Divider == 0 ) |
| embeddedartists | 0:0fdadbc3d852 | 499 | { |
| embeddedartists | 0:0fdadbc3d852 | 500 | retValue = 1 ; |
| embeddedartists | 0:0fdadbc3d852 | 501 | } |
| embeddedartists | 0:0fdadbc3d852 | 502 | else |
| embeddedartists | 0:0fdadbc3d852 | 503 | { |
| embeddedartists | 0:0fdadbc3d852 | 504 | matrixPtr->An = ((displayPtr[0].x - displayPtr[2].x) * (screenPtr[1].y - screenPtr[2].y)) - |
| embeddedartists | 0:0fdadbc3d852 | 505 | ((displayPtr[1].x - displayPtr[2].x) * (screenPtr[0].y - screenPtr[2].y)) ; |
| embeddedartists | 0:0fdadbc3d852 | 506 | matrixPtr->Bn = ((screenPtr[0].x - screenPtr[2].x) * (displayPtr[1].x - displayPtr[2].x)) - |
| embeddedartists | 0:0fdadbc3d852 | 507 | ((displayPtr[0].x - displayPtr[2].x) * (screenPtr[1].x - screenPtr[2].x)) ; |
| embeddedartists | 0:0fdadbc3d852 | 508 | matrixPtr->Cn = (screenPtr[2].x * displayPtr[1].x - screenPtr[1].x * displayPtr[2].x) * screenPtr[0].y + |
| embeddedartists | 0:0fdadbc3d852 | 509 | (screenPtr[0].x * displayPtr[2].x - screenPtr[2].x * displayPtr[0].x) * screenPtr[1].y + |
| embeddedartists | 0:0fdadbc3d852 | 510 | (screenPtr[1].x * displayPtr[0].x - screenPtr[0].x * displayPtr[1].x) * screenPtr[2].y ; |
| embeddedartists | 0:0fdadbc3d852 | 511 | matrixPtr->Dn = ((displayPtr[0].y - displayPtr[2].y) * (screenPtr[1].y - screenPtr[2].y)) - |
| embeddedartists | 0:0fdadbc3d852 | 512 | ((displayPtr[1].y - displayPtr[2].y) * (screenPtr[0].y - screenPtr[2].y)) ; |
| embeddedartists | 0:0fdadbc3d852 | 513 | |
| embeddedartists | 0:0fdadbc3d852 | 514 | matrixPtr->En = ((screenPtr[0].x - screenPtr[2].x) * (displayPtr[1].y - displayPtr[2].y)) - |
| embeddedartists | 0:0fdadbc3d852 | 515 | ((displayPtr[0].y - displayPtr[2].y) * (screenPtr[1].x - screenPtr[2].x)) ; |
| embeddedartists | 0:0fdadbc3d852 | 516 | matrixPtr->Fn = (screenPtr[2].x * displayPtr[1].y - screenPtr[1].x * displayPtr[2].y) * screenPtr[0].y + |
| embeddedartists | 0:0fdadbc3d852 | 517 | (screenPtr[0].x * displayPtr[2].y - screenPtr[2].x * displayPtr[0].y) * screenPtr[1].y + |
| embeddedartists | 0:0fdadbc3d852 | 518 | (screenPtr[1].x * displayPtr[0].y - screenPtr[0].x * displayPtr[1].y) * screenPtr[2].y ; |
| embeddedartists | 0:0fdadbc3d852 | 519 | } |
| embeddedartists | 0:0fdadbc3d852 | 520 | |
| embeddedartists | 0:0fdadbc3d852 | 521 | return( retValue ) ; |
| embeddedartists | 0:0fdadbc3d852 | 522 | } |
| embeddedartists | 0:0fdadbc3d852 | 523 | |
| embeddedartists | 0:0fdadbc3d852 | 524 | /********************************************************************** |
| embeddedartists | 0:0fdadbc3d852 | 525 | * |
| embeddedartists | 0:0fdadbc3d852 | 526 | * Function: getDisplayPoint() |
| embeddedartists | 0:0fdadbc3d852 | 527 | * |
| embeddedartists | 0:0fdadbc3d852 | 528 | * Description: Given a valid set of calibration factors and a point |
| embeddedartists | 0:0fdadbc3d852 | 529 | * value reported by the touch screen, this function |
| embeddedartists | 0:0fdadbc3d852 | 530 | * calculates and returns the true (or closest to true) |
| embeddedartists | 0:0fdadbc3d852 | 531 | * display point below the spot where the touch screen |
| embeddedartists | 0:0fdadbc3d852 | 532 | * was touched. |
| embeddedartists | 0:0fdadbc3d852 | 533 | * |
| embeddedartists | 0:0fdadbc3d852 | 534 | * |
| embeddedartists | 0:0fdadbc3d852 | 535 | * |
| embeddedartists | 0:0fdadbc3d852 | 536 | * Argument(s): displayPtr (output) - Pointer to the calculated |
| embeddedartists | 0:0fdadbc3d852 | 537 | * (true) display point. |
| embeddedartists | 0:0fdadbc3d852 | 538 | * screenPtr (input) - Pointer to the reported touch |
| embeddedartists | 0:0fdadbc3d852 | 539 | * screen point. |
| embeddedartists | 0:0fdadbc3d852 | 540 | * matrixPtr (input) - Pointer to calibration factors |
| embeddedartists | 0:0fdadbc3d852 | 541 | * matrix previously calculated |
| embeddedartists | 0:0fdadbc3d852 | 542 | * from a call to |
| embeddedartists | 0:0fdadbc3d852 | 543 | * setCalibrationMatrix() |
| embeddedartists | 0:0fdadbc3d852 | 544 | * |
| embeddedartists | 0:0fdadbc3d852 | 545 | * |
| embeddedartists | 0:0fdadbc3d852 | 546 | * The function simply solves for Xd and Yd by implementing the |
| embeddedartists | 0:0fdadbc3d852 | 547 | * computations required by the translation matrix. |
| embeddedartists | 0:0fdadbc3d852 | 548 | * |
| embeddedartists | 0:0fdadbc3d852 | 549 | * /- -\ |
| embeddedartists | 0:0fdadbc3d852 | 550 | * /- -\ /- -\ | | |
| embeddedartists | 0:0fdadbc3d852 | 551 | * | | | | | Xs | |
| embeddedartists | 0:0fdadbc3d852 | 552 | * | Xd | | A B C | | | |
| embeddedartists | 0:0fdadbc3d852 | 553 | * | | = | | * | Ys | |
| embeddedartists | 0:0fdadbc3d852 | 554 | * | Yd | | D E F | | | |
| embeddedartists | 0:0fdadbc3d852 | 555 | * | | | | | 1 | |
| embeddedartists | 0:0fdadbc3d852 | 556 | * \- -/ \- -/ | | |
| embeddedartists | 0:0fdadbc3d852 | 557 | * \- -/ |
| embeddedartists | 0:0fdadbc3d852 | 558 | * |
| embeddedartists | 0:0fdadbc3d852 | 559 | * It must be kept brief to avoid consuming CPU cycles. |
| embeddedartists | 0:0fdadbc3d852 | 560 | * |
| embeddedartists | 0:0fdadbc3d852 | 561 | * |
| embeddedartists | 0:0fdadbc3d852 | 562 | * Return: OK - the display point was correctly calculated |
| embeddedartists | 0:0fdadbc3d852 | 563 | * and its value is in the output argument. |
| embeddedartists | 0:0fdadbc3d852 | 564 | * NOT_OK - an error was detected and the function |
| embeddedartists | 0:0fdadbc3d852 | 565 | * failed to return a valid point. |
| embeddedartists | 0:0fdadbc3d852 | 566 | * |
| embeddedartists | 0:0fdadbc3d852 | 567 | * |
| embeddedartists | 0:0fdadbc3d852 | 568 | * |
| embeddedartists | 0:0fdadbc3d852 | 569 | * NOTE! NOTE! NOTE! |
| embeddedartists | 0:0fdadbc3d852 | 570 | * |
| embeddedartists | 0:0fdadbc3d852 | 571 | * setCalibrationMatrix() and getDisplayPoint() will do fine |
| embeddedartists | 0:0fdadbc3d852 | 572 | * for you as they are, provided that your digitizer |
| embeddedartists | 0:0fdadbc3d852 | 573 | * resolution does not exceed 10 bits (1024 values). Higher |
| embeddedartists | 0:0fdadbc3d852 | 574 | * resolutions may cause the integer operations to overflow |
| embeddedartists | 0:0fdadbc3d852 | 575 | * and return incorrect values. If you wish to use these |
| embeddedartists | 0:0fdadbc3d852 | 576 | * functions with digitizer resolutions of 12 bits (4096 |
| embeddedartists | 0:0fdadbc3d852 | 577 | * values) you will either have to a) use 64-bit signed |
| embeddedartists | 0:0fdadbc3d852 | 578 | * integer variables and math, or b) judiciously modify the |
| embeddedartists | 0:0fdadbc3d852 | 579 | * operations to scale results by a factor of 2 or even 4. |
| embeddedartists | 0:0fdadbc3d852 | 580 | * |
| embeddedartists | 0:0fdadbc3d852 | 581 | * |
| embeddedartists | 0:0fdadbc3d852 | 582 | */ |
| embeddedartists | 0:0fdadbc3d852 | 583 | int TSC2046::getDisplayPoint( calibPoint_t * displayPtr, |
| embeddedartists | 0:0fdadbc3d852 | 584 | calibPoint_t * screenPtr, |
| embeddedartists | 0:0fdadbc3d852 | 585 | calibMatrix_t * matrixPtr ) |
| embeddedartists | 0:0fdadbc3d852 | 586 | { |
| embeddedartists | 0:0fdadbc3d852 | 587 | int retValue = 0 ; |
| embeddedartists | 0:0fdadbc3d852 | 588 | |
| embeddedartists | 0:0fdadbc3d852 | 589 | if( matrixPtr->Divider != 0 ) |
| embeddedartists | 0:0fdadbc3d852 | 590 | { |
| embeddedartists | 0:0fdadbc3d852 | 591 | /* Operation order is important since we are doing integer */ |
| embeddedartists | 0:0fdadbc3d852 | 592 | /* math. Make sure you add all terms together before */ |
| embeddedartists | 0:0fdadbc3d852 | 593 | /* dividing, so that the remainder is not rounded off */ |
| embeddedartists | 0:0fdadbc3d852 | 594 | /* prematurely. */ |
| embeddedartists | 0:0fdadbc3d852 | 595 | displayPtr->x = ( (matrixPtr->An * screenPtr->x) + |
| embeddedartists | 0:0fdadbc3d852 | 596 | (matrixPtr->Bn * screenPtr->y) + |
| embeddedartists | 0:0fdadbc3d852 | 597 | matrixPtr->Cn |
| embeddedartists | 0:0fdadbc3d852 | 598 | ) / matrixPtr->Divider ; |
| embeddedartists | 0:0fdadbc3d852 | 599 | displayPtr->y = ( (matrixPtr->Dn * screenPtr->x) + |
| embeddedartists | 0:0fdadbc3d852 | 600 | (matrixPtr->En * screenPtr->y) + |
| embeddedartists | 0:0fdadbc3d852 | 601 | matrixPtr->Fn |
| embeddedartists | 0:0fdadbc3d852 | 602 | ) / matrixPtr->Divider ; |
| embeddedartists | 0:0fdadbc3d852 | 603 | } |
| embeddedartists | 0:0fdadbc3d852 | 604 | else |
| embeddedartists | 0:0fdadbc3d852 | 605 | { |
| embeddedartists | 0:0fdadbc3d852 | 606 | retValue = 1 ; |
| embeddedartists | 0:0fdadbc3d852 | 607 | } |
| embeddedartists | 0:0fdadbc3d852 | 608 | return( retValue ) ; |
| embeddedartists | 0:0fdadbc3d852 | 609 | } |
| embeddedartists | 0:0fdadbc3d852 | 610 | |
| embeddedartists | 0:0fdadbc3d852 | 611 | |
| embeddedartists | 0:0fdadbc3d852 | 612 | // ############################################################################ |
| embeddedartists | 0:0fdadbc3d852 | 613 | // <<<<<<<< Calibrate code <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< |
| embeddedartists | 0:0fdadbc3d852 | 614 | // ############################################################################ |
| embeddedartists | 0:0fdadbc3d852 | 615 | |
| embeddedartists | 0:0fdadbc3d852 | 616 | |
| embeddedartists | 0:0fdadbc3d852 | 617 |