Tandy 1000 SL Technical Reference Manual page 554

BIOS Services
Read Sector(s) from Diskette
Read the desired sector(s) from the diskette into RAM.
Entry Conditions
AH
=
2
DL
DH
=
head number (0-1)
CH
=
track number
(0-79)
CL
=
sector number (1-9)
AL
=
sector count (1-9)
ES:BX
=
pointer to disk buffer
=
drive number (0-2 if Tandy 1000 TL; 0-1 if Tandy
1000 SL)
Exit Conditions
See the following "Exits from all Calls."
AL
=
number of sectors read
Write Sector(s) to Diskette
Write the desired sector(s) from RAM to disk.
Entry Conditions
AH
=
3
DL
DH
=
head number (0-1)
CH
=
track number
(0-79)
CL
=
sector number (1-9)
AL
=
sector count (1-9)
ES:BX
=
pointer to disk buffer
=
drive number (0-2 if Tandy 1000 TL; 0-1 if Tandy
1000 SL)
33.