John LinqMaybe see this:Normally the Cortex-M3 wait until the previous write is completedbefore the interrupt return. However, some microcontrollers has awrite buffer in the peripheral bridge. The write buffer acceleratessingle write transfers to peripherals so that the processor don'thave to wait until the transfer is done (peripheral bus might berunning at slower clock speed).However, for clearing an interrupt request, the write bufferreply to the processor that transfer is done, while the actual writetransfer actually haven't been completed in the peripheral. So theprocessor executed interrupt return, and found that the interruptrequest from the peripheral is still high and think that it is a newinterrupt request.By Joseph Yiu.
Bruno CeldranMarc:We looked with the scope with more zoom, and clearly the pulseproduced by the button is not perfect. How to record vocals fl studio. But it won't explain the 32(or more, this is the size of the FIFO) interrupts generated.I did what you suggested, disabling the interrupts in the handler,and the button is now working fine, almost all the time.
I see thatthe interrupt is still triggered twice, when I press on the buttontoo long. Disabling the interrupts might be a workaround. But whatare the advantages/disadvantages to run all tasks in privileged mode? (I'm new to the Cortex and RTX-OS, I was working on ST10 and XC166before)John:Thanks for the link, it would explain why it works in debug. Per WestermarkTrigged twice if you keep the button pressed too long, yousay.Is it only trigged twice, or can you get many interrupts if youkeep the button pressed for 10 seconds?If you get interrupts while the button is pressed, then you haveeither failed to set the controller to be edge-trigged. Or you have aproblem with the signal level, so that noise makes the signal rippleabove/below the trig level.
Or you have failed to acknowledge theinterrupt controller, so it reenters.If you 'only' get an extra interrupt when you release the buttonagain, then you either have ripple/bounce or have failed to configurethe input to only trig on one flank - a number of processors supportsexternal interrupts to trig on high-to-low, low-to-high, both orlevel.If you combine the interrupt handling with a timer (used forreactivating the input), then the timer ISR should check the staticstate of the pin and wait more timer periods before reactivating theinterrupt, if the pin hasn't returned to the idle state. Marc CrandallAny mechanical button in my experience will cause several edgeinterrupts on both edges on a press and release.
That is the wholepoint of debouncing.A very rough method I use is to use task events.If I get an interrupt on say the rising edge the ISR disables theinterrupt and raises an event.A task is waiting for the event and when it receives the event itchecks the state of the pin for X amount of time to make sure it is apress and not a bounce.If it's a press handle the press otherwise re-enable the interruptand wait for the event again. Development Tools.Hardware & Collateral.Contact. © 2005-2019 (or its affiliates). All rights reserved. Avast secureline vpn crack + license file till 2050.
Stm32 Disable Interrupts
We can use 16 external interrupt line (line0 to line15) to detect external event from GPIO pins. Each pin from all GPIO port is connected to each external interrupt line with the same number. PA0, PB0, PC0 and so on, are multiplexed to line0. So you can only configure one of these pins to connect to line0 interrupt. PA0 and PA8 are multiplexed to different line. So you can configure these pins to use external interrupt at the same time. Because PA0 is connected to line0 and PA8 is connected to line8.
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