quadrature_encoder.h

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#ifndef libpropeller_quadrature_encoder_h__
#define libpropeller_quadrature_encoder_h__

#include <propeller.h>

extern char _load_start_quadrature_encoder_cog[];

class QuadratureEncoder {
public:

    bool Start(const int basePin, const int numberOfEncoders) {
        volatile void * asm_reference = NULL;
        __asm__ volatile ( "mov %[asm_reference], #QuadratureEncoder_Entry \n\t"
                : [asm_reference] "+r" (asm_reference));

        Stop();

        this->numberOfEncoders = numberOfEncoders;
        this->basePin = basePin;
        cog = cognew(_load_start_quadrature_encoder_cog, &this->basePin) + 1;

        return cog != 0;
    }

    void Stop(void) {
        if (cog > 0) {
            cogstop(cog - 1);
        }
    }

    int GetReading(const int index) {
        return readings[index];
    }

private:
    // Don't reorder these three volatile variables! They are used by the GAS cog.
    volatile int basePin, numberOfEncoders, readings[16];

    int cog;
};


/*
 // This function is untested!
int32_t QuadratureEncoder::Readdelta(int32_t Encid)
{
  int32_t Deltapos = 0;
  Deltapos = ((0 + ((Encid < Totdelta) * (-((int32_t *)Pos)[((*(int32_t *)&dat[196]) + Encid)]))) + (((int32_t *)Pos)[((*(int32_t *)&dat[196]) + Encid)] = ((int32_t *)Pos)[Encid]));
  return Deltapos;
}
 */

#endif // libpropeller_quadrature_encoder_h__