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Re: Interrupt vs Thread - shared resource

On Thu, 12 Feb 2009 02:58:03 +0100, Szentirmai Gergely <> wrote:


I describe my problem with a simplified example: I have a thread, which works with a buffer, and an ISR (or DSR), which would add some byte to this buffer too, so it is a shared resource. Since it is unable wait for a flag, or mutex in ISR, when the thread's code working with the buffer, the interrupt can jam the data.
The only solution is to disable the interrupt for that critical section in the thread? Isn't there a better solution?

I hope I was clear.

Gergely Szentirmai

Well, you might block just this particular interrupt while messing around
in the DSR using cyg_drv_interrupt_mask(vector) and enable it after the
critical section using the correspoding unmask-routine. This would still allow other interrupts to come through.

When a "normal" task accesses critical data that are also accessed by a DSR use cyg_drv_dsr_lock() etc.....

Happy with this? Regards

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