Beispiel für I²C: Kompaß-Modul von RP6 aus ansteuern

20240614/compass-test.c

+#include "RP6RobotBaseLib.h"
+#include "RP6I2CmasterTWI.h"
+
+void read_compass (uint16_t *x, uint16_t *y)
+{
+  uint8_t result[5];
+  I2CTWI_transmit2Bytes (0x60, 0x00, 0x02);  // set coil
+  mSleep (1);
+  I2CTWI_transmit2Bytes (0x60, 0x00, 0x04);  // reset coil
+  mSleep (5);
+  I2CTWI_transmit2Bytes (0x60, 0x00, 0x01);  // Messung starten
+  mSleep (5);                                // 5ms warten, bis Sensor fertig gemessen hat
+  I2CTWI_transmitByte (0x60, 0x01);          // Leseindex setzen
+  I2CTWI_readBytes (0x61, result, 4);        // 4 Bytes lesen. In result liegt nun (msb x, lsb x, msb y, lsb y).
+  result[0] &= 0b00001111;                   // Unwichtge Bits vom msb abschneiden
+  result[2] &= 0b00001111;
+  *x = (result[0] << 8) + result[1];         // Wert berechnen aus msb und lsb
+  *y = (result[2] << 8) + result[3];
+}
+
+int main (void)
+{
+  uint16_t compass_x = 0;
+  uint16_t compass_y = 0;
+  initRobotBase ();
+  I2CTWI_initMaster (100);
+  powerON ();
+  changeDirection (RIGHT);
+  moveAtSpeed (20, 20);
+  startStopwatch1 ();
+  while (1)
+    {
+      task_RP6System ();
+      if (getStopwatch1 () > 200)
+        {
+          read_compass (&compass_x, &compass_y);
+          writeInteger (compass_x, DEC);
+          writeChar (' ');
+          writeInteger (compass_y, DEC);
+          writeChar ('\n');
+          setStopwatch1 (0);
+        }
+    }
+}