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fazli
Posts: 87
hi, all simmer
hi planning running my trim stab wheels.
i used uln 2003 board link to arduino mega.
the function is, when i push button on yoke wheel stab on motorized. and then when push auto pilot wheel stab also running.
1.can i use uln 2003 board for running 12v motor stepper.
2.what offset no can i choices.

regards
fazli
2018-09-08 06:57
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pizman82
Moderator
From: ETSI, Germany
Posts: 2958
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For Offset you must know if your Aircraft have a own.... Some AddOns got i think.

Else use the Elevator Trim Offsets.... Like 0BC0

Again... The AddOn is verry important here..... FSUIPC support more special offsets like radians, and direct Motor Commands and Axis values.
You must do some testing here i think !

Last Note.... Remember the UL Board and Mobiflight work with a Zero Point.
If your Trimwheel for exemple is designed to make 100 Full 360° from Trim Zero to Trim Full..... And at startup trim is in middle Position then Mobiflight must turn the motor maby 50 Times before you can start..... if you will stop Mobiflight after landing then it will turn the trimwheel same 50 times again counterclockwise to reach Zero Point again !

Thats maby a bad fact.... You can think about setting Zero Point in the Middle Position ( need a little recalculation of values.... But so the initial and shoutdown procedure is more comfortable !
Good Luck !
2018-09-08 09:07
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StephanHo
From: EDDG, Germany
Posts: 1404
Supporter
ignore this message
Hi fazli,

a 12V stepper will not work if you control it via the ULN2003.

This is controlled by 5V from the MEGA and can then drive no 12V stepper. Take the 5V stepper, which definitely works with the ULN2003.
[Last edited by StephanHo, 2018-09-08 21:43]
Grüße,
Stephan
2018-09-08 12:23
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StephanHo
From: EDDG, Germany
Posts: 1404
Supporter
After studying the datasheet I have to revise my last message.
It is quite possible to operate the motor AND the ULN2003 with 12V.
The 12V are connected to terminal 9 of the ULN2003. It is important to connect the GND of the 12V voltage source to the GND of the MEGA.

This is possible due to the built-in 500mA high-performance Darlington transistor stages in the ULN2003. At Google there are many illustrated circuit examples for the ULN2003.
Grüße,
Stephan
2018-09-08 21:43
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fazli
Posts: 87
hi stephan
tq for your answer. can you give me link drawing connection about that.
i worry about mega board.ground pin which one. at mega board have more than. one more thing. board ULN2003 terminal 9 ?
*sory my English poor.
2018-09-09 20:35
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StephanHo
From: EDDG, Germany
Posts: 1404
Supporter
hi fazli,

the MEGA-GND is to be connected to terminal 8 of ULN2003. Which GND of the MEGA you take does no matter.

The 12V are to be connected to terminal 9 of the ULN2003.

An example for a circuit diagram you'll find here: https://myframe.co/stepper-motor-driver-ic-uln2003/ Take the third image from the left in the 2nd line
Grüße,
Stephan
2018-09-09 22:53
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fazli
Posts: 87
tq,,. info
2018-09-11 20:16
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