interrupt-handling

I have an Arduino Uno (awesome little device!). It has two interrupts; let's call them 0 and 1 . I attach a handler to interrupt 0 and a different one to interrupt 1, using attachInterrupt() : http://www.arduino.cc/en/Reference/AttachInterrupt . Interrupt 0 is triggered and it calls its handler, which does some number crunching. If interrupt 0 's handler is still executing when interrupt 1 is triggered, what will happen? Will interrupt 1 interrupt interrupt 0 , or will interrupt 1 wait until interrupt 0 's handler is done executing? Please note that this question specifically relates to

I'm writing something on the linux scheduler and I need to know which process was running before my interrupt came in.. is the current structure available? If I do current->pid while in the interrupt handler, do I get the pid of the process I interrupted? You can, current->pid exists and is the process that was interrupted (may be the idle thread, or any). If you're writing inside the Linux scheduler, you should be very careful. current is changed by the scheduler as it chooses a new process to run, so its value depends on when exactly you read it. I wouldn't expect current to be valid outside

When you disable interrupts (with the cli instruction in x86), what exactly happens? Does the PIC wait for you to turn on interrupts, and fire the interrupt when that happens? (If so, how long does it wait, and what happens if the time 'expires'?) Does the interrupt -- from the device's perspective -- get sent into a "black hole", with no response? Does the PIC somehow tell the device that "the CPU is busy" or something? Or does something else happen? Also, how do you deal with an interrupt you don't know how to handle? Is there some way to tell the PIC (or the device, if you don't know what

I am trying to understand Asynchronous Interrupt handling in kernel, ofcourse through the legendary Understanding the Linux Kernel. In this process how and who will trigger Kernel Interrupt Handler? I would like some one to help me correcting this and to clarify my question on 1)How and Who trigger Kernel Interrupt Handler? 2)How to define new or change existing hardware interrupt handlers? Thank you in Advance! This picture from Robert Love's "Linux Kernel Development" pretty well describes path of interrupt. Processor interrupts the kernel in the predefined enty point do_IRQ() . If there is

As the title suggests, I'm trying to replace the existing handler for the Timer interrupt in DOS with one of my own. After searching far and wide for a variety of solutions, I found some Assembly code which does exactly that, and I have even managed to compile and test it, and saw that it works. The problem now is that the code I found (see further down) is written for TASM, and I wish to use it with some C code that I'm writing, which I compile with GCC. I've tried to convert the code into GAS (GNU Assembler) syntax, but I can't seem to get it to work (I mostly experienced crashes of one kind

I managed to load a small kernel into memory via a bootloader that performs a far jump to 0x0090:0x0000 . The kernel is loaded successfully as I print a character from there to test it and it works properly. I wanted to remap interrupts 0x08->0x0F and 0x70->0x77 to interrupts 0x20->0x2F , so the exception/reserved interrupts are not overlapped. So far, I am only handling a keyboard press and attempting to print it to the screen. I went over it a bunch of times and for some reason, I just don't know why but nothing happens when I press a key. The keymap is just an array of the scancodes to

My java program use an external method(i dont have the source code) that takes a while to finish so i have made the call to that method in a Thread class (in its run method). Now the problem is how do I stop the Thread instantly (not wait for the method to end) if user wants to exit program. When I call my Thread's interrupt method nothing happens, no interrupted exception before the external method is finished. I thought an interrupted exception could occur and be caught at the same time that the external method is running but maybe not? I'm not sure how about how Threads works exactly. So