gold@aecom.UUCP (05/11/84)
DOS 2.1 slowed down the disk head settle time to make it compatable with the pc jr. The easiest way to fix this is to replace the settle time (now 25 I think) in RAM , a harder way would be to replace this on the disk. The vector for the location of the disk table is interupt 30, so the location of the table is 30*4 bytes per interupt or 120 decimal ( segment 0 ) . the first two bytes hold the offset and the second two hold the segment. you must write a program to read the memory locationthe vector holds and check that address + 10 bytes for the offset of the head settle time. replace that value with 0. It should not be too hard to do. This information was taken from Peter Norton's book Inside The IBM PC. His description is a lot clearer than mine and you may want to look at it for more details. yosef gold ( philabs/aecom/gold )