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Unread 16-01-2014, 22:45
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Iaquinto.Joe Iaquinto.Joe is offline
RPI 2018
AKA: Joe Iaquinto
FRC #0308 (The Monsters)
Team Role: Alumni
 
Join Date: Jan 2013
Rookie Year: 2011
Location: United States
Posts: 166
Iaquinto.Joe is a jewel in the roughIaquinto.Joe is a jewel in the roughIaquinto.Joe is a jewel in the rough
Lightbulb SubVI Re-entrant Option

Our team is using a subvi to take an encoder and our optimal speed in in/s to control our drivetrain with 4 custom PID controls. We had 4 of these SubVIs (One for each wheel) and we were running into an issue where all of the PIDs were all tied together (When you manually twisted a wheel, all of them moved to compensate). We searched for awhile and we learned that when you have multiple instances of the same VI, their IO is shared on the same memory. This can be stopped by going to the front panel of the SubVI, right clicking the icon in the top right, going to VI Options, going to Execution in the drop down, and checking the radio button under "Preallocated clone reentrant execution". This allows you to call the same subvi on your crio multiple times. You will most likely need this for any custom VIs you create. I just thought this was a little obscure and deserves a thread for clarity. Good luck!
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4 year 2011 - 2014 FRC team 308 member, Lead Programmer - C++ / LabVIEW

3 year 2011, 2013, 2014 OCCRA member, Co-Captain OCCRA team 308
  • OCCRA Engineering Excellence - Waterford Kettering 2013
  • Innovation in Control - 2011
  • Quality award- Northville 2012
  • Engineering Excellence- Howell 2014
  • Innovation in Controls- Livonia 2014

Last edited by Iaquinto.Joe : 16-01-2014 at 22:46. Reason: Clarity.
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