diff options
Diffstat (limited to 'drivers/tsd/tsd_com.c')
| -rw-r--r-- | drivers/tsd/tsd_com.c | 390 |
1 files changed, 390 insertions, 0 deletions
diff --git a/drivers/tsd/tsd_com.c b/drivers/tsd/tsd_com.c new file mode 100644 index 0000000..a930cc9 --- /dev/null +++ b/drivers/tsd/tsd_com.c @@ -0,0 +1,390 @@ +/* ----------------------------------------------------------------------------
+ * ATMEL Microcontroller Software Support
+ * ----------------------------------------------------------------------------
+ * Copyright (c) 2008, Atmel Corporation
+ *
+ * All rights reserved.
+ *
+ * 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 disclaimer below.
+ *
+ * Atmel's name may not be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
+ * DISCLAIMED. IN NO EVENT SHALL ATMEL 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.
+ * ----------------------------------------------------------------------------
+ */
+
+//------------------------------------------------------------------------------
+// Headers
+//------------------------------------------------------------------------------
+
+#include "tsd.h"
+#include <board.h>
+#include <irq/irq.h>
+#include <pio/pio.h>
+#include <drivers/lcd/lcdd.h>
+#include <drivers/lcd/draw.h>
+#include <drivers/lcd/font.h>
+#include <drivers/lcd/color.h>
+#include <string.h>
+#include <utility/assert.h>
+
+//------------------------------------------------------------------------------
+// Local definitions
+//------------------------------------------------------------------------------
+
+/// Size in pixels of calibration points.
+#define POINTS_SIZE 4
+/// Maximum difference in pixels between the test point and the measured point.
+#define POINTS_MAX_ERROR 8
+
+/// Delay at the end of calibartion for result display (positive or negative)
+#define DELAY_RESULT_DISPLAY 4000000
+
+//------------------------------------------------------------------------------
+// Local types
+//------------------------------------------------------------------------------
+
+//------------------------------------------------------------------------------
+/// Point used during the touchscreen calibration process.
+//------------------------------------------------------------------------------
+typedef struct _CalibrationPoint {
+
+ /// Coordinate of point along the X-axis of the screen.
+ unsigned int x;
+ /// Coordinate of point along the Y-axis of the screen.
+ unsigned int y;
+ /// Calibration data of point.
+ unsigned int data[2];
+
+} CalibrationPoint;
+
+//------------------------------------------------------------------------------
+// Local variables
+//------------------------------------------------------------------------------
+
+/// indicates if the touch screen has been calibrated.
+/// If not, Callback functions are not called
+static volatile unsigned char bCalibrationOk = 0;
+/// Slope for interpoling touchscreen measurements along the X-axis.
+static signed int xSlope;
+/// Slope for interpoling touchscreen measurements along the Y-axis.
+static signed int ySlope;
+
+/// Calibration points
+static CalibrationPoint calibrationPoints[] = {
+
+ // Top-left corner calibration point
+ {
+ BOARD_LCD_WIDTH / 10,
+ BOARD_LCD_HEIGHT / 10,
+ {0, 0}
+ },
+ // Top-right corner calibration point
+ {
+ BOARD_LCD_WIDTH - BOARD_LCD_WIDTH / 10,
+ BOARD_LCD_HEIGHT / 10,
+ {0, 0}
+ },
+ // Bottom-right corner calibration point
+ {
+ BOARD_LCD_WIDTH - BOARD_LCD_WIDTH / 10,
+ BOARD_LCD_HEIGHT - BOARD_LCD_HEIGHT / 10,
+ {0, 0}
+ },
+ // Bottom-left corner calibration point
+ {
+ BOARD_LCD_WIDTH / 10,
+ BOARD_LCD_HEIGHT - BOARD_LCD_HEIGHT / 10,
+ {0, 0}
+ }
+};
+
+/// Test point
+static const CalibrationPoint testPoint = {
+ BOARD_LCD_WIDTH / 2,
+ BOARD_LCD_HEIGHT / 2,
+ {0, 0}
+};
+
+//------------------------------------------------------------------------------
+// External functions
+//------------------------------------------------------------------------------
+
+extern void TSD_GetRawMeasurement(unsigned int *pData);
+extern void TSD_WaitPenPressed(void);
+extern void TSD_WaitPenReleased(void);
+
+//------------------------------------------------------------------------------
+// Local functions
+//------------------------------------------------------------------------------
+
+//------------------------------------------------------------------------------
+/// Display a calibration point on the given buffer.
+/// \param pLcdBuffer LCD buffer to draw on.
+/// \param pPoint Calibration point to display.
+//------------------------------------------------------------------------------
+static void DrawCalibrationPoint(
+ void *pLcdBuffer,
+ const CalibrationPoint *pPoint)
+{
+ LCDD_DrawRectangle(pLcdBuffer,
+ pPoint->x - POINTS_SIZE / 2,
+ pPoint->y - POINTS_SIZE / 2,
+ POINTS_SIZE,
+ POINTS_SIZE,
+ COLOR_RED);
+}
+
+//------------------------------------------------------------------------------
+/// Clears a calibration point from the given buffer.
+/// \param pLcdBuffer LCD buffer to draw on.
+/// \param pPoint Calibration point to clear.
+//------------------------------------------------------------------------------
+static void ClearCalibrationPoint(
+ void *pLcdBuffer,
+ const CalibrationPoint *pPoint)
+{
+ LCDD_DrawRectangle(pLcdBuffer,
+ pPoint->x - POINTS_SIZE / 2,
+ pPoint->y - POINTS_SIZE / 2,
+ POINTS_SIZE,
+ POINTS_SIZE,
+ COLOR_WHITE);
+}
+
+//------------------------------------------------------------------------------
+// Global functions
+//------------------------------------------------------------------------------
+
+//------------------------------------------------------------------------------
+/// Indicates if the calibration of the touch screen is Ok
+/// \return 1 calibration Ok, 0 if not
+//------------------------------------------------------------------------------
+unsigned char TSDCom_IsCalibrationOk(void)
+{
+ if (bCalibrationOk == 1) {
+ return 1;
+ } else {
+ return 0;
+ }
+}
+
+//------------------------------------------------------------------------------
+/// Interpolates the provided raw measurements using the previously calculated
+/// slope. The resulting x and y coordinates are stored in an array.
+/// \param pData Raw measurement data, as returned by TSD_GetRawMeasurement().
+/// \param pPoint Array in which x and y will be stored.
+//------------------------------------------------------------------------------
+void TSDCom_InterpolateMeasurement(const unsigned int *pData, unsigned int *pPoint)
+{
+ pPoint[0] = calibrationPoints[0].x
+ - (((signed int) calibrationPoints[0].data[0] - (signed int) pData[0]) * 1024)
+ / xSlope;
+
+ pPoint[1] = calibrationPoints[0].y
+ - (((signed int) calibrationPoints[0].data[1] - (signed int) pData[1]) * 1024)
+ / ySlope;
+
+ if(pPoint[0] & 0x80000000) // Is pPoint[0] negative ?
+ {
+ pPoint[0] = 0;
+ }
+
+ if(pPoint[0] > BOARD_LCD_WIDTH) // Is pPoint[0] bigger than the LCD width ?
+ {
+ pPoint[0] = BOARD_LCD_WIDTH;
+ }
+
+ if(pPoint[1] & 0x80000000) // Is pPoint[1] negative ?
+ {
+ pPoint[1] = 0;
+ }
+
+ if(pPoint[1] > BOARD_LCD_HEIGHT) // Is pPoint[1] bigger than the LCD width ?
+ {
+ pPoint[1] = BOARD_LCD_HEIGHT;
+ }
+}
+
+//------------------------------------------------------------------------------
+/// Performs the calibration process using the provided buffer to display
+/// information.
+/// \param pLcdBuffer LCD buffer to display.
+/// \return True if calibration was successful; otherwise false.
+//------------------------------------------------------------------------------
+unsigned char TSDCom_Calibrate(void *pLcdBuffer)
+{
+#ifdef AT91C_ID_LCDC
+ void *pOldLcdBuffer;
+#endif
+ volatile unsigned int i; // to keep the tempo with gcc code optimisation
+ signed int slope1, slope2;
+ CalibrationPoint measuredPoint;
+ unsigned char xOk, yOk;
+ signed int xDiff, yDiff;
+
+ // Calibration setup
+ LCDD_Fill(pLcdBuffer, COLOR_WHITE);
+ LCDD_DrawString(pLcdBuffer, 30, 50, "LCD calibration", COLOR_BLACK);
+ LCDD_DrawString(pLcdBuffer, 1, 100, " Touch the dots to\ncalibrate the screen", COLOR_DARKBLUE);
+#ifdef AT91C_ID_LCDC
+ pOldLcdBuffer = LCDD_DisplayBuffer(pLcdBuffer);
+#endif
+
+ // Calibration points
+ for (i=0; i < 4; i++) {
+
+ DrawCalibrationPoint(pLcdBuffer, &calibrationPoints[i]);
+
+ // Wait for touch & end of conversion
+ TSD_WaitPenPressed();
+ TSD_GetRawMeasurement(calibrationPoints[i].data);
+ ClearCalibrationPoint(pLcdBuffer, &calibrationPoints[i]);
+
+ // Wait for contact loss
+ TSD_WaitPenReleased();
+ }
+
+ // Calculate slopes using the calibration data
+ // Theory behind those calculations:
+ // - We suppose the touchscreen measurements are linear, so the following equations are true (simple
+ // linear regression) for any two 'a' and 'b' points of the screen:
+ // dx = (a.data[0] - b.data[0]) / (a.x - b.x)
+ // dy = (a.data[1] - b.data[1]) / (a.y - b.y)
+ //
+ // - We calculate dx and dy (called xslope and yslope here) using the calibration points.
+ //
+ // - We can then use dx and dy to infer the position of a point 'p' given the measurements performed
+ // by the touchscreen ('c' is any of the calibration points):
+ // dx = (p.data[0] - c.data[0]) / (p.x - c.x)
+ // dy = (p.data[1] - c.data[1]) / (p.y - c.y)
+ // Thus:
+ // p.x = c.x - (p.data[0] - c.data[0]) / dx
+ // p.y = c.y - (p.data[1] - c.data[1]) / dy
+ //
+ // - Since there are four calibration points, dx and dy can be calculated twice, so we average
+ // the two values.
+ slope1 = ((signed int) calibrationPoints[0].data[0]) - ((signed int) calibrationPoints[1].data[0]);
+ slope1 *= 1024;
+ slope1 /= ((signed int) calibrationPoints[0].x) - ((signed int) calibrationPoints[1].x);
+ slope2 = ((signed int) calibrationPoints[2].data[0]) - ((signed int) calibrationPoints[3].data[0]);
+ slope2 *= 1024;
+ slope2 /= ((signed int) calibrationPoints[2].x) - ((signed int) calibrationPoints[3].x);
+ xSlope = (slope1 + slope2) / 2;
+
+ slope1 = ((signed int) calibrationPoints[0].data[1]) - ((signed int) calibrationPoints[2].data[1]);
+ slope1 *= 1024;
+ slope1 /= ((signed int) calibrationPoints[0].y) - ((signed int) calibrationPoints[2].y);
+ slope2 = ((signed int) calibrationPoints[1].data[1]) - ((signed int) calibrationPoints[3].data[1]);
+ slope2 *= 1024;
+ slope2 /= ((signed int) calibrationPoints[1].y) - ((signed int) calibrationPoints[3].y);
+ ySlope = (slope1 + slope2) / 2;
+
+ // Test point
+ LCDD_Fill(pLcdBuffer, 0xFFFFFF);
+ LCDD_DrawString(pLcdBuffer, 30, 50, "LCD calibration", COLOR_BLACK);
+ LCDD_DrawString(pLcdBuffer, 1, 100, " Touch the point to\nvalidate calibration", COLOR_DARKBLUE);
+ DrawCalibrationPoint(pLcdBuffer, &testPoint);
+
+ // Wait for touch & end of conversion
+ TSD_WaitPenPressed();
+
+ TSD_GetRawMeasurement(measuredPoint.data);
+ TSDCom_InterpolateMeasurement(measuredPoint.data, (unsigned int *) &measuredPoint);
+ DrawCalibrationPoint(pLcdBuffer, &measuredPoint);
+
+ // Check resulting x and y
+ xDiff = (signed int) measuredPoint.x - (signed int) testPoint.x;
+ yDiff = (signed int) measuredPoint.y - (signed int) testPoint.y;
+ xOk = (xDiff >= -POINTS_MAX_ERROR) && (xDiff <= POINTS_MAX_ERROR);
+ yOk = (yDiff >= -POINTS_MAX_ERROR) && (yDiff <= POINTS_MAX_ERROR);
+
+ // Wait for contact loss
+ TSD_WaitPenReleased();
+
+ // Check calibration result
+ if (xOk && yOk) {
+
+ bCalibrationOk = 1;
+ LCDD_Fill(pLcdBuffer, COLOR_WHITE);
+ LCDD_DrawString(pLcdBuffer, 30, 50, "LCD calibration", COLOR_BLACK);
+ LCDD_DrawString(pLcdBuffer, 80, 100, "Success !", COLOR_GREEN);
+
+ }
+ else {
+
+ bCalibrationOk = 0;
+ LCDD_Fill(pLcdBuffer, COLOR_WHITE);
+ LCDD_DrawString(pLcdBuffer, 30, 50, "LCD calibration", COLOR_BLACK);
+ LCDD_DrawString(pLcdBuffer, 40, 100, "Error too big", COLOR_RED);
+ }
+
+ // Slight delay
+ for (i = 0; i < DELAY_RESULT_DISPLAY; i++);
+
+#ifdef AT91C_ID_LCDC
+ // Restore old LCD buffer
+ LCDD_DisplayBuffer(pOldLcdBuffer);
+#endif
+
+ return (xOk && yOk);
+}
+
+//------------------------------------------------------------------------------
+/// Read calibrate data to buffer.
+/// \param pBuffer Data buffer.
+/// \param size Size of data buffer in bytes.
+//------------------------------------------------------------------------------
+void TSDCom_ReadCalibrateData(void *pBuffer, unsigned int size)
+{
+ unsigned char *pDest = (unsigned char *)pBuffer;
+
+ SANITY_CHECK((sizeof(bCalibrationOk) + sizeof(xSlope) +
+ sizeof(ySlope) + sizeof(calibrationPoints[0].data)) < size);
+
+ memcpy(pDest, (void const *)&bCalibrationOk, sizeof(bCalibrationOk));
+ pDest += sizeof(bCalibrationOk);
+ memcpy(pDest, &xSlope, sizeof(xSlope));
+ pDest += sizeof(xSlope);
+ memcpy(pDest, &ySlope, sizeof(ySlope));
+ pDest += sizeof(ySlope);
+ memcpy(pDest, &calibrationPoints[0].data, sizeof(calibrationPoints[0].data));
+ pDest += sizeof(calibrationPoints[0].data);
+}
+
+//------------------------------------------------------------------------------
+/// Restore calibrate data with buffer data.
+/// \param pBuffer Data buffer.
+/// \param size Size of data buffer in bytes.
+//------------------------------------------------------------------------------
+void TSDCom_RestoreCalibrateData(void *pBuffer, unsigned int size)
+{
+ unsigned char *pSrc = (unsigned char *)pBuffer;
+
+ SANITY_CHECK((sizeof(bCalibrationOk) + sizeof(xSlope) +
+ sizeof(ySlope) + sizeof(calibrationPoints[0].data)) < size);
+
+ memcpy((void *)&bCalibrationOk, pSrc, sizeof(bCalibrationOk));
+ pSrc += sizeof(bCalibrationOk);
+ memcpy(&xSlope, pSrc, sizeof(xSlope));
+ pSrc += sizeof(xSlope);
+ memcpy(&ySlope, pSrc, sizeof(ySlope));
+ pSrc += sizeof(ySlope);
+ memcpy(&calibrationPoints[0].data, pSrc, sizeof(calibrationPoints[0].data));
+ pSrc += sizeof(calibrationPoints[0].data);
+}
+
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