loops and exceptions

[Adek336]

hi I have an exception system up, and when I try infintive looping, I get an exception. Also it does when I have sumfin like for(i = 1; i<1000; i++) {code()}
it blocks it.

It works only if I CLI.

Is this normal behaviour?

Thnx, Adrian.

[jamethiel]

Are you sure you're catching an exception from your code, and not from a hardware interrupt?

[carbonBased]

Indeed!  Have you redirected hardware interrupts to beyond 0x20?

Also, which exception?  There are many   I could see an alignment exception being caused... but you'd have to voluntarily set the alignment bit in... CR0 (?) I think, as well as eflags.  Most ppl don't do this   (my OS, on the other hand, will cause an exception at any unaligned code... I wanna make sure all my apps are properly compiled )

Jeff

[Adek336]

Ahh! I considered the timer, but then I moved my research to keyboards. I am just trying to get my IRQ working but it doh runs only once. Haven't forgotten about outportb(0x20, 0x20).

Any suggestions?

Thnx, Adrian.

[carbonBased]

> Any suggestions?

Yeah!  Actually write the ISR

The keyboard interrupt will only be recognised if the keyboard knows you've received the last keystroke, so-to-speak.  In other words, in your keyboard ISR, be sure to actually _get_ the keystroke (inportb(0x60) iirc), then all should work as expected.

Cheers!
Jeff

[Adek336]

you're a genius! now it works

now i get a "hello world" message each keystroke.

Thnx, Adrian.

Thanx