Tandy 1000 HX Technical Reference Manual page 409

Disk I/O Support for the Floppy Only
System Configuration
Software Interrupt:
13 hex (19 dec)
Function Summary:
AH = 0: Reset Floppy Disk
AH = 1: Return Status of Last Floppy Disk Operation
AH = 2: Read Sector(s) from Floppy Disk
AH = 3: Write Sector(s) to Floppy Disk
AH = 4: Verify Sector(s) on Floppy Disk
AH = 5: Format Track on Floppy Disk
Function Descriptions:
Reset Floppy Disk
Reset the diskette system. Resets associated hardware and
recalibrates all diskette drives.
Entry Conditions:
AH = 0
Exit Conditions:
See "Exits From All Calls" below.
Return Status of Last Floppy Disk Operation
Return the diskette status of the last operation in AH.
Entry Conditions
AH = 1
Exit Conditions:
AL = status of the last operation; see "Exits From All Calls"
below for values
Read Sector(s) from Floppy Disk
Read the desired sector(s) from disk into RAM.
19