Author Topic: Pulse width  (Read 12902 times)

DAlgie

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Pulse width
« on: November 10, 2011, 06:58:33 PM »
Hi, I am trying to output a varying pulse width signal. I need it to be between 1ms and 2ms, in tenths of a ms. This is from a FMD1616. I read all the literature and is is unclear if this is possible. The older TMD 1616 had only a certain amount of fixed pulse frequencies I believe.

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Re:Pulse width
« Reply #1 on: November 11, 2011, 01:12:13 AM »
Yes, you can use the SETPWM command to set the duty cycle and the frequency of a PWM output. For FMD PLC the frequency is continuously variable between 50Hz and 50KHz so you can create a wave form with very accurate frequency/period, and you can compute the duty cycle required to generate the pulsewidth of your choice.

Are you trying to control a RC Servo with 1ms to 2ms signal? Section 11.4 in the FMD PLC User's Manual Section describes how this can be achieved.
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DAlgie

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Re:Pulse width
« Reply #2 on: November 11, 2011, 05:57:36 AM »
Yes, that's it exactly, need to control a number of RC servos (among other things). PAGE 11.4 of the users manual (the book)only shows For...Next statements, which users manual do you mean?

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Re:Pulse width
« Reply #3 on: November 11, 2011, 08:37:21 AM »
Email: support@triplc.com
Tel: 1-877-TRI-PLCS

DAlgie

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Re:Pulse width
« Reply #4 on: November 11, 2011, 11:28:11 AM »
Thank you, that is it exactly.