Steve,
As far as I know the XIRQ interrupt is level sensitive, and cannot be configured to edge sensitive. In any case, usually the XIRQ does not need to be edge sensitive, since it has a higher priority than all other interrupts, and is also not masked when other interrupts are masked. this is since the XIRQ interrupt depends on the CCR register "X" interrupt mask bit, rather than the CCR register "I" interrupt mask bit (The "X" bit does not change when you code processes a normal "I" bit interrupt, so once the XIRQ interrupt is enabled using the CCR register "X" bit, the XIRQ interrupts are always enabled - until the next Reset). Hope this helps, Doron Nohau HC12 In-Circuit Emulators www.nohau.com/emul12pc.html At 18:43 08/04/2005 -0500, you wrote: >I have looked thru the documentation until I am frustrated. >Does anyone know if the XIRQ pin is level sensitive or edge sensitive by >default? >Can XIRQ be modified to edge sensitive like the IRQ pin? If so, which >register modifies this? > >Regards, > >Steve Dillier > >HighPoint Design LLC [Non-text portions of this message have been removed] Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/68HC12/ <*> To unsubscribe from this group, send an email to: [hidden email] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/ |
Nope. ~XIRQ is strictly level-senitive, and cannot be reversed.
A logic 0 will always trigger the interrupt if it's enabled. > Date: Thu, 09 Jun 2005 10:38:11 +0300 > From: Doron Fael <[hidden email]> > Subject: Re: Is XIRQ level or edge sensitive? > > Steve, > > As far as I know the XIRQ interrupt is level sensitive, and cannot be > configured to edge sensitive. > > In any case, usually the XIRQ does not need to be edge sensitive, since it > has a higher priority than all other interrupts, and is also not masked > when other interrupts are masked. this is since the XIRQ interrupt depends > on the CCR register "X" interrupt mask bit, rather than the CCR register > "I" interrupt mask bit (The "X" bit does not change when you code > processes > a normal "I" bit interrupt, so once the XIRQ interrupt is enabled using > the > CCR register "X" bit, the XIRQ interrupts are always enabled - until the > next Reset). > > Hope this helps, > Doron > Nohau > HC12 In-Circuit Emulators > www.nohau.com/emul12pc.html > > > At 18:43 08/04/2005 -0500, you wrote: >>I have looked thru the documentation until I am frustrated. >>Does anyone know if the XIRQ pin is level sensitive or edge sensitive by >>default? >>Can XIRQ be modified to edge sensitive like the IRQ pin? If so, which >>register modifies this? >> >>Regards, >> >>Steve Dillier >> >>HighPoint Design LLC > > > [Non-text portions of this message have been removed] > > > > ________________________________________________________________________ > ________________________________________________________________________ > > > > ------------------------------------------------------------------------ > Yahoo! Groups Links > > > > > ------------------------------------------------------------------------ > > > > Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/68HC12/ <*> To unsubscribe from this group, send an email to: [hidden email] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/ |
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