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hi i have irq1 linked to interrupt 33 for my keyboard isr
right now i just have it output a colored letter in the corner of screen everytime this interrupt is called so i can see how often it is being called. i ran the os and the keyboard interrupt, along with the timer interrupt were each being called frequently. what i am wondering is how to get what data is waiting from the keyboard and how to check if there is more data there or not before i exit the isr. i think it has something to do with ports 60h and 61h but i am not sure exactly how to read/write these.

thanks in advance

Supposedly, it's just a matter of reading port 0x60 to read and acknowledge the data byte.

And that reading is typically accomplished by an IN AL, 60h instruction.

i have done the in al, 0x60 and i get 0xFA coming from port 0x60 every time the interrupt occurs

i also read somewhere to reset the controller to do the following:

in al, 0x61
mov ah, al
or al, 0x80
out 0x60, al
mov al, ah
out 0x61, al

if i dont do this, then the interrupt only occurs once. if i do this after reading port 0x60 every time the interrupt is run, it continues to be triggered constantly, but every time 0xFA is returned from port 0x60, even when i do not press any keys. if i do press a key, every once in a while a different value is read, but most of the time 0xFA is returned...

Please tell me that the "out 0x60, al" is a typo, and the real code says 0x61. Please?

If it isn't then I wouldn't be at all suprised that you're getting wierd behavior loke that.

lol sometimes thinking too technically causes me to overlook the obvious ones thanks, ill check that on my other computer tomorrow, i'll bet that's it because i copied the code

thanks

if that is it, then is that the entire procedure to acknowledge and clear the keypress?

It should be, yes.