Pigpiod : Get stepper position after cancelling the wave

Question

I am using pigpiod C interface to drive the Nema17 Stepper Motors by DRV8825 / stepper drivers. I am able to drive the motors by wave_chain() method.

After calling the wave_chain() method, it starts the pulse the stepper. If I cancel the transmitting process of the current wave form by wave_tx_stop(), can I get the current stepper position or all information is lost when I call the wave_tx_stop()?

I am using this code to drive the motor ;

void generate_ramp(int step_pin, int ramp0, int ramp1)
{
    int wid = -1;
    int f = ramp0;
    int micros = (int)(500000/f);
    gpioPulse_t pulses[2] =  {{1 << step_pin, 0, micros},{0, 1 << step_pin,micros}};
    wave_add_generic(Global.pi, 2, pulses);

    wid = wave_create(Global.pi);

    int steps = ramp1;
    int x = steps & 255;
    int y = steps >> 8;
    char wave[7] = {255, 0, wid, 255, 1 , x, y};
    wave_chain(Global.pi, wave , 7);
    while(wave_tx_busy(Global.pi));

    wave_delete(Global.pi, wid);
}

Maybe combination of wave_tx_at() and wave_tx_stop() will helpful, but I can't find any way to remember the position just before the cancelling the transmitting.

Answer 1

No.

The information is held internally within the DMA blocks but there is no method to get that information.