Category:8086 Assembly: Difference between revisions
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→Data Registers: Formatting fixes
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===Data Registers===
There are four data registers: <code>AX</code>, <code>BX</code>, <code>CX</code>, and <code>DX</code>. While most commands can use any of them, some only work with particular data registers. System calls in particular are very specific about which registers can be used for what. On [[MS-DOS]], the <code>AX</code> register is used for selecting the desired interrupt to use with the <code>INT</code> command.
Each data register is 16-bit, but has two eight bit halves ending in H or L, e.g. <code>AH, AL</code>. Instructions can be executed using the whole register or just half of it.
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