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??? The function INT 13h/AH=42h does not use cylinders, it's for LBA addressing mode. Besides, error code 1 (returned AH=1) is:JamesBond wrote:I am trying to use teh INT 13 AH=42 to read a sector of a hard disk that have more than 1023 cylinders but this service
returns an error at AH=01 and don't read the sectors! What can i make?
Have you checked that your drive supports extended read function? Do you provide a valid pointer in DS:SI? Does your disk address packet contain valid values (number of sectors reasonable and buffer pointer valid)?01h invalid function in AH or invalid parameter
I think that address pack may have an error but how check if teh drive support INT 13h AH=42h ?turdus wrote:JamesBond wrote:I am trying to use teh INT 13 AH=42 to read a sector of a hard disk that have more than 1023 cylinders but this service
returns an error at AH=01 and don't read the sectors! What can i make?Have you checked that your drive supports extended read function? Do you provide a valid pointer in DS:SI? Does your disk address packet contain valid values (number of sectors reasonable and buffer pointer valid)?
JamesBond wrote: I think that address pack may have an error but how check if teh drive support INT 13h AH=42h ?
Code: Select all
MOV AX,4100H ; EDD INSTALLATION CHECK
MOV BX,55AAH
MOV DL,[Boot_Drive]
INT 13H
JC @Not_Supported
CMP BX,0AA55H
JNZ @Not_Supported
TEST CX,1
JZ @Not_Supported
here is part of the code:
Code: Select all
mov ah,42
mov dl,80
mov si,200
INT 13
disk address packet = 1000010300100000000000
The Numbers are decimal instead of HexadecimalGriwes wrote:Where is the error at the code above?
No! All the numbers are hexadecimaldjmauretto wrote:The Numbers are decimal instead of HexadecimalGriwes wrote:Where is the error at the code above?
Griwes wrote:No, to be hexadecimal, they would have to have 0x prefix, or h suffix
No! No! No! because my assembler don't need the h suffix not even teh 0x prefix The assembler is created by me! This assembler use only hexadecimal numbers!iansjack wrote:Which assembler would that be? It seems to use a non-standard syntax.
And how do you tell it when you do want to specify a decimal number?
You've probably pinpointed your problem there. Try comparing the generated code with that from a mainline assembler.JamesBond wrote:The assembler is created by me!