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1. 

   hans
   Member

   Is there a way to remove jitter in the ISR without disbling the USB.
   I need to be able place the Maple into a mode where it only handles ISRs. It can ignore all USB commands during this time. After a certain event the ISR will be disabled and I then need to be able to receive USB commands again. Disabling the USB causes it to be removed from the device manager and my software looses conneection.
   Any help woul be apprecieated.
   - Hans

   Posted 3 years ago #
2. 

   gbulmer
   Moderator

   "Is there a way to remove jitter in the ISR without disbling the USB."
   Not easily.
   "It can ignore all USB commands during this time."
   A host polls a USB device every millisecond (or more frequently), and if the device doesn't respond, the host system will eventually think it is 'dead'.

   One approach would be to 'drop' the USB pull-up resistor, do the ISR's, then pull the resistor up again, which will trigger the host to re-enumerate the device if it has been 'off' long enough. An alternative is to use a separate USB to serial cable, and communicate with the host via that, never enabling USB.

   (Full disclosure: I am not a member of LeafLabs staff.)

   Posted 3 years ago #

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