Diff: TSC2046.h

Revision:

0:0fdadbc3d852

Child:

4:b32cf4ef45c5

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/TSC2046.h	Thu Sep 26 06:37:02 2013 +0000
@@ -0,0 +1,99 @@
+
+#ifndef TSC2046_H
+#define TSC2046_H
+
+
+/**
+ * Texas Instruments Touch Screen Controller (TSC2046).
+ */
+class TSC2046 {
+public:
+
+    typedef struct {
+        int32_t x;
+        int32_t y;
+        int32_t z;
+    } touchCoordinate_t;
+
+    /**
+     * Constructor
+     *
+     * @param mosi SPI MOSI pin
+     * @param miso SPI MISO pin
+     * @param sck SPI SCK pin
+     * @param cs chip-select pin
+     */
+    TSC2046(PinName mosi, PinName miso, PinName sck, PinName cs);
+
+    /**
+     * Read coordinates from the touch panel.
+     *
+     * Before calibrate() is called this function will return uncalibrated
+     * values. If there is no touch active the coordinate values will be 0.
+     *
+     * @param coord pointer to coordinate object. The read coordinates will be
+     * written to this object.
+     */
+    void read(touchCoordinate_t &coord);
+
+    /**
+     * Calibrate touch screen based on three reference points and
+     * three actual readings. This means that the user must be presented
+     * with three points (one at a time) and asked to press on these points
+     * to get an actual reading.
+     */
+    void calibrate(touchCoordinate_t &ref1,
+            touchCoordinate_t &ref2,
+            touchCoordinate_t &ref3,
+            touchCoordinate_t &scr1,
+            touchCoordinate_t &scr2,
+            touchCoordinate_t &scr3);
+
+    /**
+     * Reset a previous calibration (in order to do a new calibration)
+     */
+    void uncalibrate();
+
+
+private:
+
+    typedef struct {
+        int64_t x;
+        int64_t y;
+    } calibPoint_t;
+
+    typedef struct {
+        int64_t An;
+        int64_t Bn;
+        int64_t Cn;
+        int64_t Dn;
+        int64_t En;
+        int64_t Fn;
+        int64_t Divider;
+    } calibMatrix_t;
+
+    SPI _spi;
+    DigitalOut _cs;
+    bool _calibrated;
+    bool _initialized;
+    calibMatrix_t _calibMatrix;
+
+    void init();
+    void readAndFilter(touchCoordinate_t &coord);
+    int32_t getFilteredValue(int cmd);
+    uint16_t spiTransfer(uint8_t cmd);
+
+
+
+    int setCalibrationMatrix( calibPoint_t * displayPtr,
+            calibPoint_t * screenPtr,
+            calibMatrix_t * matrixPtr);
+    int getDisplayPoint( calibPoint_t * displayPtr,
+            calibPoint_t * screenPtr,
+            calibMatrix_t * matrixPtr );
+
+};
+
+#endif
+
+