31 lines
735 B
C
31 lines
735 B
C
// Utilities for writing to and reading from I/O ports
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#include "ports.h"
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byte vga_readb(u16 port) {
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// Reads a byte from the specified I/O port
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byte result;
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__asm__("in %%dx, %%al" : "=a" (result) : "d" (port));
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return result;
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}
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void vga_writeb(u16 port, byte data) {
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// Writes a byte to the specified I/O port
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__asm__("out %%al, %%dx" : : "a" (data), "d" (port));
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}
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u16 vga_readw(u16 port) {
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// Reads a word (16 bits) from the specified I/O port
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u16 result;
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__asm__("in %%dx, %%ax" : "=a" (result) : "d" (port));
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return result;
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}
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void vga_writew(u16 port, u16 data) {
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// Writes a word (16 bits) to the specified I/O port
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__asm__("out %%ax, %%dx" : : "a" (data), "d" (port));
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} |