1991/0709/pc/io.h (diff list | history)

pc/io.h on 1991/0703
1991/0703		/*
1991/0709		* programmable interrupt vectors (for the 8259)
1991/0703		*/
1991/0704		enum {
1991/0706		Int0vec= 16, /* first interrupt vector used by the 8259 */
1991/0704		Clockvec= Int0vec+0, /* clock interrupts */ Kbdvec= Int0vec+1, /* keyboard interrupts */
1991/0703		}; /*
1991/0704		* 8237 dma controllers */ enum { /* * the byte registers for DMA0 are all one byte apart */ Dma0= 0x00, Dma0status= Dma0+0x8, /* status port */ Dma0reset= Dma0+0xD, /* reset port */ /* * the byte registers for DMA1 are all two bytes apart (why?) */ Dma1= 0xC0, Dma1status= Dma1+2*0x8, /* status port */
1991/0705		Dma1reset= Dma1+2*0xD, /* reset port */
1991/0704		};