Questions tagged [machine-code]
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7 questions
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Why is the destination register encoded in a different place for MUL(S) on ARM?
This question is about the instructions MUL and MULS (hereinafter, just Multiply), which were introduced with the ARM2, and the encoding of the register operands. In this context, Rd refers to the ...
- 41.2k
4
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Why does the VIC-20 tinymon relocator escape $00 bytes?
Jim Butterfields tinymon1 monitor for the VIC-20 was distributed as a BASIC program with appended machine language code, as is typical for many CBM machine-language programs.
However, in this case the ...
- 29.5k
9
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1
answer
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Triggering Amstrad BASIC/System errors from machine code
I'm writing some machine code that's intended to be executed from BASIC with a CALL and I'd like to trigger genuine errors just like running ERROR 5 (Improper argument) from BASIC.
I have the book The ...
- 2,669
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How can I run a machine language program off the disk drive on an Apple II?
Apple II was the first computer I used and programmed on, but only in BASIC, and back in 1979. I learned machine code on my ZX Spectrum which was tape only.
On Apple II how do you load/run a machine ...
- 8,214
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What does it mean to "publish machine code"?
The Wikipedia article on “An Open Letter to Hobbysts” says that Bill Gates complained about hobbyists pirating his software, and due to piracy he refused to publish the machine code of his Altair ...
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15
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Difference between machine language and machine code, maybe in the C64 community?
I've always been sure that "machine language" and "machine code" are totally synonymous and mean programming directly in the language the machine understands, whether in binary, ...
- 8,214
9
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Why does the LGP-30 leave half its instruction word unused?
I am looking at the machine code for the LGP-30, which is found to have a very strange instruction word layout.
12 ignored bits
4 bits for the opcode
2 more ignored bits
12 bits for the operand, ...
- 41.2k