Friends, I managed to shoot the camera through the cable using canon a2400 with chdk. A sequence of settings:
1 - BRD_PWM_count must be 4;
2 - SERVO5_FUNCTION must be 89 (mini pix does not use AUX but MAIN);
3 - RELAY_PIN put 54;
4 - CAM_TRIGG_TYPE put 1.
I was successful and the camera is working normally, the secret is in steps 2 and 3.