Use a negative transition gate to send a stop command upon the signal going low. That has yielded some good results for me in the past.
What others are saying.? Because serial is a one time command (versus IR being able to continuously send a command), usually cameras that are RS232 or IP controlled, use a pan/tilt command to start moving and require a stop command of some sort when you release the button on the touch panel.? Depending on the camera, it will either be a move stop, or some cameras have separate pan-stop, tilt-stop, zoom-stop commands that may need to be sent to make it stop doing that particular motion that was started.
Presets normally do not need to stop, they will do so when they reach the desired position.
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Jason Mussetter
Control Systems Designer
Mussetter Programming Services
