Diff: at42qt2120.cpp

Revision:

0:fa7450a43b99

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/at42qt2120.cpp	Mon Dec 04 09:32:20 2017 +0000
@@ -0,0 +1,150 @@
+//
+// Filename: at42qt2120.cpp
+//
+// Atmel AT42QT2120 12 channel touch sensor.
+//
+
+#include "at42qt2120.h"
+
+#include "log.h"
+
+namespace HAL {
+
+// This chip has a singe fixed I2C address.
+const int ADDRESS =  0x1c;
+
+// Chip Id hardcoded in the silicon.
+const int AT42QT2120_ID = 0x3e;
+    
+AT42QT2120::AT42QT2120(I2C &i2cin)
+: i2c(i2cin)
+{
+#ifdef VERBOSE
+    if(Read((REG_AT42QT2120) QT_CHIP_ID) != AT42QT2120_ID)
+        Log("AT42QT2120 bad chip id");
+    else
+        Log("AT42QT2120 chip id: Ok");
+    
+    char version[20];
+    int ver = Read((REG_AT42QT2120) QT_FIRMWARE_VERSION);
+    sprintf(version, "AT42QT2120 version: %u.%u", ver >> 4, ver & 0x0f);
+    Log(version);
+#endif
+
+    for(uint8_t key = 0; key < 12; key++)
+        SetKeyControl(key, false, 0, false, false);
+
+    Calibrate();
+}
+
+bool AT42QT2120::ReadStatus(Status &status)
+{
+    char buffer[4];
+
+    buffer[0] = Read(QT_DETECTION_STATUS);
+    buffer[1] = Read(QT_KEY_STATUS);
+    buffer[2] = Read(QT_KEY_STATUS2);
+    buffer[3] = Read(QT_SLIDER_POSITION);
+
+#ifdef VERBOSE
+    char msg[32];
+    sprintf(msg, "Touch: %x %x %x %x", buffer[0], buffer[1], buffer[2], buffer[3]);
+#endif
+
+    status.keyschanged = (buffer[0] & TDET) != 0;
+    status.keys = buffer[2];
+    status.keys = status.keys << 8;
+    status.keys += buffer[1];
+
+    status.sliderchanged = (buffer[0] & SDET) != 0;
+    status.slider = buffer[3];
+
+    return true;
+}
+
+bool AT42QT2120::Calibrate()
+{
+#ifdef VERBOSE
+    Log("AT42QT2120 calibration start");
+#endif
+
+    bool status = Write(QT_CALIBRATE, 0xff);
+    if(status)
+    {
+        while(Read(QT_DETECTION_STATUS) & 0x80);
+    }
+
+#ifdef VERBOSE
+    if(status)
+        Log("AT42QT2120 calibration finish");
+    else
+        Log("AT42QT2120 calibration fail");
+#endif
+    return status;
+}
+
+bool AT42QT2120::SetKeyControl(uint8_t key, bool guard, uint8_t group, bool gpo, bool enable)
+{
+    bool status = false;
+
+    if(key < 12 && group < 4)
+    {
+        uint8_t config = 0;
+        if(!enable)
+            config |= CTRL_EN;
+        if(gpo)
+            config |= CTRL_GPO;
+        if(group)
+            config |= group << 2;
+        if(guard)
+            config |= CTRL_GUARD;
+
+        uint8_t reg = key + 28; // 28 = QT_KEY0_CTRL
+        status = Write((HAL::REG_AT42QT2120) reg, config);
+    }
+
+    return status;
+}
+
+void AT42QT2120::SetSliderOptions(SLIDERMODE_AT42QT2120 mode)
+{
+    switch(mode)
+    {
+        case SLIDER:
+            Write(QT_SLIDER_OPTION, 0x80);
+            break;
+
+        case WHEEL:
+            Write(QT_SLIDER_OPTION, 0xc0);
+            break;
+
+        default:
+            Write(QT_SLIDER_OPTION, 0x0);
+            break;
+    }
+}
+
+int AT42QT2120::Read(REG_AT42QT2120 reg)
+{
+    if(i2c.write(ADDRESS << 1, (const char *) &reg, 1, true))
+    {
+        i2c.stop();
+        return 0;
+    }
+
+    char data[2];
+	i2c.read(ADDRESS << 1, data, 1);
+
+    return data[0];
+}
+
+bool AT42QT2120::Write(REG_AT42QT2120 reg, uint8_t value)
+{
+    uint8_t regnum = reg;
+    const char data[2] = { regnum, value };
+
+    return i2c.write(ADDRESS << 1, data, 2) == 0;
+}
+
+} // End HAL namespace.
+