// Il suffit de définir ses PINs et d'appeler dans le loop ReadRotary()

#define MLCLK		VALBIT1		// B1=CLK (tout à droite, opposé au -)
#define MLDATA		VALBIT0		// B0=DATA (à gauche de CLK)

// Retourne la variation 1, 0, ou -1
int ReadRotary()
{  // Robust Rotary encoder reading - Copyright John Main - best-microcontroller-projects.com
   // A vald CW or  CCW move returns 1, invalid returns 0.
   static uint8_t prevNextCode = 0;
   static uint16_t store = 0;
   static int8_t rot_enc_table[] = {0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0};
   TU_ENTIER16 v16 = GPIOB->regs->IDR;
   prevNextCode <<= 2;
   if (v16 & MLDATA) prevNextCode |= 0x02;
   if (v16 & MLCLK) prevNextCode |= 0x01;
   prevNextCode &= 0x0f;
   // If valid then store as 16 bit data.
   if (rot_enc_table[prevNextCode])
   {  store <<= 4;
      store |= prevNextCode;
      //if (store==0xd42b) return 1;
      //if (store==0xe817) return -1;
      if ((store&0xff)==0x2b) return -1;
      if ((store&0xff)==0x17) return 1;
   }
   return 0;
}