interrupt

Enabling Interrupts in U-boot for ARM cortex A-9

别来无恙 提交于 2019-11-27 06:22:16
问题 I am trying to configure a GPIO interrupt in the uboot, This it to test the Interrupt response time without any OS intervention (Bare-metal). I was able to configure the pin-muxing and also successful in setting up the interrupt with the GPIO pin. My question is regarding the registering of the interrupt service routine. I see that the Interrupt vector table for my platform is at address 0xFFFF0000 ( I read the System Control Register to find out this). The interrupt Id for the GPIO was 56

How processor handles case of division by zero

穿精又带淫゛_ 提交于 2019-11-27 06:15:01
问题 Curious what the processor/CPU does in general or let say, on intel cpu & Linux, when it executes a division by zero instruction. Also how the error is relayed to the application, so that it can log the error or notify the developer? Thank you! 回答1: To answer in general terms, rather than going into gory details for Linux on x86_64, which are likely to obscure the concepts. CPUs tend to throw an exception interrupt, on things like division by zero, or dereferencing a NULL pointer. These

What is INT 21h?

99封情书 提交于 2019-11-27 03:36:11
问题 Inspired by this question How can I force GDB to disassemble? I wondered about the INT 21h as a concept. Now, I have some very rusty knowledge of the internals, but not so many details. I remember that in C64 you had regular Interrupts and Non Maskable Interrupts, but my knowledge stops here. Could you please give me some clue ? Is it a DOS related strategy ? 回答1: From here: A multipurpose DOS interrupt used for various functions including reading the keyboard and writing to the console and

How to interrupt a BlockingQueue which is blocking on take()?

天涯浪子 提交于 2019-11-27 03:09:00
I have a class that takes objects from a BlockingQueue and processes them by calling take() in a continuous loop. At some point I know that no more objects will be added to the queue. How do I interrupt the take() method so that it stops blocking? Here's the class that processes the objects: public class MyObjHandler implements Runnable { private final BlockingQueue<MyObj> queue; public class MyObjHandler(BlockingQueue queue) { this.queue = queue; } public void run() { try { while (true) { MyObj obj = queue.take(); // process obj here // ... } } catch (InterruptedException e) { Thread

Java long running task Thread interrupt vs cancel flag

青春壹個敷衍的年華 提交于 2019-11-27 01:09:50
问题 I have a long running task, something like: public void myCancellableTask() { while ( someCondition ) { checkIfCancelRequested(); doSomeWork(); } } The task can be cancelled (a cancel is requested and checkIfCancelRequested() checks the cancel flag). Generally when I write cancellable loops like this, I use a flag to indicate that a cancel has been requested. But, I know I could also use Thread.interrupt and check if the thread has been interrupted. I'm not sure which would be the preferred

dma vs interrupt-driven i/o

有些话、适合烂在心里 提交于 2019-11-27 00:39:25
问题 I'm a little unclear on differences between DMA and interrupt I/O. (Currently reading Operating Systems Concepts, 7th ed). Specifically, I'm not sure when the interrupts occur in either case, and at what points in both cases is the CPU is free to do other work. Things I've been reading, but can't necessarily reconcile: Interrupt-driven Controller initialized via driver Controller examines registers loaded by driver in order to decide action Data transfer from/to peripheral and controller's

What is the difference between FIQ and IRQ interrupt system?

若如初见. 提交于 2019-11-26 23:31:32
I want to know the difference between FIQ and IRQ interrupt system in any microprocessor, e.g: ARM926EJ. A feature of modern ARM CPUs (and some others). From the patent: A method of performing a fast interrupt in a digital data processor having the capability of handling more than one interrupt is provided. When a fast interrupt request is received a flag is set and the program counter and condition code registers are stored on a stack. At the end of the interrupt servicing routine the return from interrupt instructions retrieves the condition code register which contains the status of the

Enabling floating point interrupts on Mac OS X Intel

不羁的心 提交于 2019-11-26 20:24:54
问题 On Linux, feenableexcept and fedisableexcept can be used to control the generation of SIGFPE interrupts on floating point exceptions. How can I do this on Mac OS X Intel? Inline assembly for enabling floating point interrupts is provided in http://developer.apple.com/documentation/Performance/Conceptual/Mac_OSX_Numerics/Mac_OSX_Numerics.pdf, pp. 7-15, but only for PowerPC assembly. 回答1: Exceptions for sse can be enabled using _MM_SET_EXCEPTION_MASK from xmmintrin.h . For example, to enable

Uninterruptable process in Windows(or Linux)?

爷,独闯天下 提交于 2019-11-26 20:15:25
问题 Is there any way to make a program that cannot be interrupted (an uninterrupted program)? By that, I mean a process that can't be terminated by any signal, kill command, or any other key combinations in any System: Linux, windows etc. First, I am interested to know whether it's possible or not. And if yes, upto what extend it is possible? I mostly write code in C, C++, and python; but I don't know any of such command(s) available in these programming languages. Is it possible with assembly

How to interrupt java.util.Scanner nextLine call

时光怂恿深爱的人放手 提交于 2019-11-26 18:32:06
问题 I am using a multi threaded environment were one Thread is constantly listening for user input by repeatedly calling scanner.nextLine() . To end the application, this runloop is stopped by another thread, but the listening thread won't stop until a last user input was made (due to the blocking nature of nextLine() ). Closing the stream seems not to be an option since I am reading from System.in , which returns an InputStream that is not closable. Is there a way to interrupt the blocking of