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How to increase rate of zoom /shift using RS232 commands

Any way to incease rate of lens zoom or lens shift. Is there a minimum 'wait'?
please see below

Just a quick Thank you to all who advised me with ideas/tips and tricks
Thinking about the problem and initially getting thwarted I decided that if Rs232 control was so finicky or( I was so dense) I should have a back up plan. I decided to learn the IRs for the projector and try that way.
Sure enough after choosing the right syntax I got it to work. Well I could not stop there so i redid my RS232 command strings and I now can control zoom up and down fairly well. I changed the waits between strings being sent and it is now zooming up or down as needed. doing a push release works fairly well. The zoom was so little intially I thought is was doing nothing but indeed it was zooming up or down in very small increments.
One last question( I hope) . Can I increase the rate of the zoom function? It will zoom up or down but takes way longer then when I use IR pulses
Code for RS232 below:
curu and curd are variables
















I have changed the WAIT to 1 and it works better can I make the wait even less?
Tried messing around with pulse times also
Thanks in advance
I feel I have learned more this past week around some of my programming issues then in months
I do not do this everyday as you can tell.


  • DHawthorneDHawthorne Old Timer Posts: 4,584
    It really depends on the device and its serial port. Most of them are considerably slower than the IR, and there is nothing you can do about it.

    WAIT 1 is as shout as a WAIT will go; I never tried doing WAIT 0, but it might actually work by just putting it on the stack and firing it immediately on the next mainline pass. It's worth trying if you are not comfortable with timeline programming. If it doesn't do the job, you will have to convert to a repeating timeline, where you can get resolution down to the millisecond. It's just a bit more convoluted to set up: I would send a single command on the PUSH, and only create the timeline to ramp it on a HOLD, making it so the first timeline event only fires after the hold time is met. That makes it easier to fine adjust with single pushes when you get close. Then kill the timeline on the RELEASE.

    However, all that said, you have a hard limit on how fast the device responds to the serial port. If you send commands faster than its internal response interval, they may (again, depending on how it handles the port) stack up and keep on going after you release the button, and you definitely don't want that. The only way to know is play around with it.
  • Joe HebertJoe Hebert Junior Member Posts: 2,159
    DHawthorne wrote: »
    WAIT 1 is as short as a WAIT will go;
    You can express a WAIT as a fraction so if you do a WAIT .1 you can get it down to 100th of a second if you want.
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