ivers read and write I/O ports on Intel-based computers. Use <b>inb()</b> to read a byte at the I/O port <i>address</i>. Use <b>inw()</b> to read the two bytes at <i>address</i> and <i>address</i> + 1, and <b>inl()</b> to read four bytes starting at <i>address</i>. To write a byte, use <b>outb()</b>; to write two bytes (to <i>address</i> and <i>address</i> + 1), use <b>outw()</b>; to write four bytes, use <b>outl()</b>.</font></td></tr>

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