All Questions
Tagged with machine-code assembly
8 questions
1
vote
1
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385
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Intel Memory Addressing Form
I'm am trying to understand machine code memory addressing for x86, and I've encountered two opposing general forms for addressing (using the ModRM and SIB bytes).
Most unofficial resources I consult ...
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-2
votes
1
answer
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What is 16 bit word's equivalent in decimal?
Question:
For a 16 bit word with 6 bits for an opcode
How many different instructions could I fit into the instruction set?
What is the largest number that I could use as data?
Answer:...
- 265
14
votes
7
answers
40k
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"Write an Assembler in C." Why writing a machine code translator for a low level language in a higher level language?
My Microprocessor class instructor gave us an assignment and said:
"Write an Assembler in C." - My beloved Professor
So it seemed a little bit illogical to me.
If I'm not wrong Assembly ...
- 265
1
vote
3
answers
2k
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Operation excution in terms of clock cycles
Typically for a single instrcution, 6 machine cycles are needed:
FETCH instruction
DECODE instruction
EVALUATE ADDRESS
fetch OPERANDS
EXECUTE oepration
STORE result
My concern is regarding the fifth ...
- 147
3
votes
4
answers
3k
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How does assembly relate to machine/binary code
How does assembly relate to machine/binary code.
For example here is how to print to the screen in mikeOS(a small pure assembly OS), mikeOS it uses NASM to assemble.
BITS 16
ORG 32768
%...
- 365
0
votes
1
answer
1k
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Fetching instructions from memory
So, I am a noob in assembly language and machine instructions.
When the discussion came up as to how funtion calls are implemented at the processor level, someone said that the CALL instruction ...
- 11
1
vote
1
answer
666
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What did machine code for 4-bit architecture look like?
I don't know how a 4-bit instruction could be enough to do something so I read about the Intel 4004 and it says that it used 8-bit instructions and then I can understand how opcode and numbers has ...
- 8,108
3
votes
3
answers
553
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Is it possible to use GNU GPL for application that has no source?
I mean, it is possible to create application without source code - for example using HEX editor or some debugger that can assembly instructions (actually every decent debugger can).
Creating programs ...
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