here's some of my favourite x86 assembler interrupts. i hope that you enjoy these as much as i do.
read light pen position
int 10h service 4
input
AH = 4
output
AH = 0
ligth pen switch not down
AH = 1
DH, DL = row, column of light pen position
CH = raster line (vertical) 0 - 199
BX = pixel column (horizontal) 0 - 319, 639
park heads ps/2 only
int 13h service 19h
input
DL = drive number
output
carry = 0
success
carry = 1
error : AH = error code
cassette i/o
int 15h
input
AH = 0
turn cassette motor on
AH = 1
turn cassette motor off
AH = 2
read one or more 256 byte blocks.
store data at ES:BX CX = count of bytes to read
AH = 3
write one or more 256 byte blocks from ES:BX count of bytes to write in CX
output
DX = number of bytes actually read. carry flag set if error
carry = 1
AH = 1 : crc error
AH = 2 : data transitions lost
AH = 4 : no data found
resident basic
int 18h
this interrupt starts up rom-resident basic in the pc