(C/C++) How can i try to use something like jc?

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NunoLava1998
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(C/C++) How can i try to use something like jc?

Post by NunoLava1998 »

I finally got to enable interrupts correctly (using my code and code of some other people, no errors or warnings using -Wextra/-Wall). However, my code sometimes fails to enable interrupts, and so i need something like a jc to repeat if the carry flag was set, or a rfics (repeat function if carry flag set).

How would i do this in C (or C++)? Yes, i use inline assembly to do lidt.
Developing TRIODIUM OS. Or call it Dixium if you want. It doesn't matter.

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iansjack
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Re: (C/C++) How can i try to use something like jc?

Post by iansjack »

What has the carry flag got to do with enabling interrupts?
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Post by Techel »

Why would you want to check the carry flag?
Simply use the jc instruction with a destination label.
NunoLava1998
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Re: Techel

Post by NunoLava1998 »

Techel wrote:Why would you want to check the carry flag?
Simply use the jc instruction with a destination label.
My loading interrupts function fails a lot, and since i try to use the PIC right after, it triple-faults (obviously).
Developing TRIODIUM OS. Or call it Dixium if you want. It doesn't matter.

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Re: (C/C++) How can i try to use something like jc?

Post by NunoLava1998 »

iansjack wrote:What has the carry flag got to do with enabling interrupts?
lidt can fail sometimes (and it does, it sometimes takes like 5 times until it finally does it succesfully).
Developing TRIODIUM OS. Or call it Dixium if you want. It doesn't matter.

https://github.com/NunoLava1998/DixiumOS
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iansjack
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Re: (C/C++) How can i try to use something like jc?

Post by iansjack »

NunoLava1998 wrote:
iansjack wrote:What has the carry flag got to do with enabling interrupts?
lidt can fail sometimes (and it does, it sometimes takes like 5 times until it finally does it succesfully).
But what has that got to do with the carry flag? And what is difficult about enabling interrupts - it's a single instruction.
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Post by Techel »

Did you clear the interrupt enabled flag before lidt'ing the idt? If not, the pit keeps triggering interrupts, but if you're lucky, this doesn't happen until you got the interrupt part successfully set up.
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Re: Techel

Post by NunoLava1998 »

Techel wrote:Did you clear the interrupt enabled flag before lidt'ing the idt? If not, the pit keeps triggering interrupts, but if you're lucky, this doesn't happen until you got the interrupt part successfully set up.
Looks like that is , sometimes i can get it for a bit before PIT screws up.
Developing TRIODIUM OS. Or call it Dixium if you want. It doesn't matter.

https://github.com/NunoLava1998/DixiumOS
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