expand the test program

uvosled.h

@@ -15,23 +15,29 @@ struct uvosled {
 	struct usbshm* priv;
 };
 
+// returns 0 on sucess and < 0 on failure
 int uvosled_connect(struct uvosled* led);
 
 // power on cameras
+// returns 0 on sucess and < 0 on failure
 int uvosled_poweron(struct uvosled* led);
 
 // power off cameras
+// returns 0 on sucess and < 0 on failure
 int uvosled_poweroff(struct uvosled* led);
 
 // channels is a mask of bits, you can set it like this: CHANNEL_A | CHANNEL_C to activate channels A and C
-// current is in Ampere
+// current is in percent of the values selected by the linear regulator resistors
+// returns 0 on sucess and < 0 on failure
 int uvosled_set_current(struct uvosled* led, uint8_t channels, float current);
 
 // causes the cameras to take an image
+// returns 0 on sucess and < 0 on failure
 int uvosled_trigger(struct uvosled* led);
 
 // leds are lit for time seconds and the camera is activated cameraOffset seconds after they are lit
 // real time guarenteed by microcontroller
+// returns 0 on sucess and < 0 on failure
 int uvosled_capture(struct uvosled* led, int channels, float current, double time, double cameraOffset);
 
 void uvosled_disconnect(struct uvosled* led);