Lecture 24

DMA Request Register

DMA Mask–1 Register

DMA Mask–2 Register

DMA Mode Register

Setup & Query of DMA Channels

High Address Nibble/Byte

#include <dos.h> #include <bios.h> char st[80]; unsigned long int temp; unsigned int i; unsigned int count=48; void main (void) { temp=(unsigned long int)_DS; temp = temp << 4L; i = *((unsigned int *)(&temp)); temp = temp>>16L;

outportb (0x81,*((unsigned char *)(&temp))); outportb(0x06,*(((unsigned char *)(&i)))); outportb(0x06,*(((unsigned char *)(&i))+1)); count--; outportb(0x07,*((unsigned char *)(&count))); outportb(0x07,*(((unsigned char*)(&count))+1)); outportb(0x0b,0x0b); outportb(0x08,0); outport(0x0a,3); getch(); }