MS-DOS uses INT 21H for its main API functions which provide a low-level is the assembly code to transfer data from one file to other using INT 21H?. INT is an assembly language instruction for x86 processors that generates a software interrupt. For example, INT 21H will generate the software interrupt 0x21 (33 in decimal), causing the function pointed to by the 34th vector in the interrupt. int 21h Dos Interrupt. Int 21h is a common function. The INT 21H instruction in is a software interrupt to vector 21H. It is used for input/output operations.
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Abraham Jacob 51 1 1.
This is accomplished by entering a bit value corresponding to a kernel function into the EAX register of the processor and then executing INT 0x Geoffrey 6, 2 17 This simply means that you are using function 01h of the Interrupt type By calling it with different parameters in the registers mostly ah and al you could access various IO operations, string output and more.
assembly language int 21h Dos Interrupt
It is therefore entirely possible to use a far-call instruction to start the interrupt-function manually after pushing the flag register.
INT (x86 instruction) – Wikipedia
Philip Kirkbride 7, 26 82 Post as a guest Name. BOSS 8 23 Other INT instructions are encoded using two bytes. INT is an assembly language instruction for x86 processors that generates a software interrupt. Most Unix systems and derivatives do not use software interrupts, with the exception of interrupt 0x80, used to make system calls.
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INT (x86 instruction)
Instruction Set Reference Manual”. Retrieved from ” https: It takes the interrupt number formatted as a byte value.
Email Required, but never shown. From Wikipedia, the free encyclopedia. The INT 3 instruction is defined for use by debuggers to temporarily replace an instruction in a running program in order to set a breakpoint. For example, INT 21H will generate the software interrupt 0x21 33 in decimalcausing the function pointed to by the 34th vector in the interrupt table to be executed, 21n is typically a DOS API call.