Codes about 8259A are :(from Christopher Giese,a bit changed) mov al,0x11 ; icw1-->11:icw4 is needed out 0x20,al out 0xa0,al mov al,0x20 ; icw2:vector for IRQs begining out 0x21,al ; IRQ0-IRQ7 -> interrupts 0x20-0x27 add al,8 out 0xa1,al mov al,4 ; icw3 out 0x21,al mov al,2 out 0xa1,al mov al,1fh ; icw4 out 0x21,al mov al,1bh out 0xa1,al mov al,0xFc ;ocw out 0x21,al and Codes for INT 21: int_21: mov si,msg_int20 ; 'Pressed key...' inc dh ;dh->row for display call Print ;routine for video output,param with dx & si. in al,60h iretd when I press a key, it display the message twice, like this: Pressed key...
Pressed key... and it was no responds when press again.
thanks. user4
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