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onlyonemac wrote:So is refusing to help someone until after they've fumbled around with trying to figure out how to use a debugger that they are not yet experienced enough to understand.

BASICFreak wrote:Wow, I knew this was going to be a flame war, but come on people.

@OP: If you still having issues post your code and I'll (and hopefully another) will go threw it and explain what is wrong, no I will not fix it and give it back - only help you fix it.

StartOS wrote:

Artlav wrote: Are you sure your GDT is correct and loaded?

Yes, it is.

• Null
• Kernel Code - PL0, Base 0, Offset 0xFFFFFFFF
• Kernel Data - PL0, Base 0, Offset 0xFFFFFFFF
• User Code - PL3, Base 0, Offset 0xFFFFFFFF
• User Data - PL3 Base 0, Offset 0xFFFFFFFF

onlyonemac wrote:I'm glad you got your problem sorted out. I too have run into problems using DDs and DWs. The thing to remember is that with the x86 architecture, the least-significant byte is stored first. So if you say "DD 0x1234", the actual values in memory will be "0x34 0x12". This is not a problem as such because this is the way that the CPU expects it to be when reading the GDT, but when you chain together multiple DDs to make a DW (for example), you need to remember to do this manually, so e.g. to store "DW 0x12345678" you need to write "DD 0x5678\nDD 0x1234" to keep the bytes in the correct order as if they were a DW.

@iansjack: I bet he didn't even know about the "info gdt" command in Bochs. So he would have gone through all the trouble of setting up Boches, most likely given up on his project alltogether because setting up Bochs was really not what he wanted to be doing, and still not have had a solution to his problem.

onlyonemac wrote:Unrelated, but I get annoyed that not any assembler that I have seen has a data directive for a 64-bit (4-byte) word

DB, DW, DD, DQ, DT, DO, DY and DZ are used, much as in MASM, to declare initialized data in the output file. They can be invoked in a wide range of ways:

db 0x55 ; just the byte 0x55
db 0x55,0x56,0x57 ; three bytes in succession
db 'a',0x55 ; character constants are OK
db 'hello',13,10,'$' ; so are string constants
dw 0x1234 ; 0x34 0x12
dw 'a' ; 0x61 0x00 (it's just a number)
dw 'ab' ; 0x61 0x62 (character constant)
dw 'abc' ; 0x61 0x62 0x63 0x00 (string)
dd 0x12345678 ; 0x78 0x56 0x34 0x12
dd 1.234567e20 ; floating-point constant
dq 0x123456789abcdef0 ; eight byte constant
dq 1.234567e20 ; double-precision float
dt 1.234567e20 ; extended-precision float
DT, DO, DY and DZ do not accept numeric constants as operands.

iansjack wrote:the corresponding directives for a 4-byte word are "dd" and ".word"

iansjack wrote:

@iansjack: I bet he didn't even know about the "info gdt" command in Bochs. So he would have gone through all the trouble of setting up Boches, most likely given up on his project alltogether because setting up Bochs was really not what he wanted to be doing, and still not have had a solution to his problem.

You seem to have a very low opinion of the intelligence of people on this forum. You have, in this thread, continually told us that the OP wouldn't understand this or wouldn't understand that. I believe you are mistaken. The third post in this thread told the OP about the "info gdt" command in Bochs.

Basically you have spent the thread trying to push your own, erroneous, interpretation of the problem on the OP without considering other possibilities or even sensibly examining the evidence provided. Just let it rest, accept that you were wrong, and accept that the OP has decided to take the very sensible advice that he was given.

The problem has been solved and that's the end of my interest in it.

onlyonemac wrote:I was just saying that we cannot assume anything about the intellegence of a newbie.