Western Digital T13/2132-D - Manual (Page 55)

June 23, 2010 T13/2132-D Revision 3
Working Draft Enhanced Disk Drive - 4 (EDD-4) 43
8.15 Extended Read (FN 42h)
This function shall transfer sectors from the device to memory. In the event of an error, the block count field of
the device address packet contains the number of good blocks read before the error occurred.
Entry
AH 42h
DL BIOS device number
DS:SI Pointer to Device Address Packet (see table 9)
Exit
Carry Clear Function completed without error
AH Shall be cleared to zero
Carry Set Function completed with an error
AH Shall be set to the error code