HelenOS sources

EGA_INDEX_REG     467 kernel/genarch/src/drivers/ega/ega.c 		pio_write_8(instance->base + EGA_INDEX_REG, 0x0a);
EGA_INDEX_REG     469 kernel/genarch/src/drivers/ega/ega.c 		pio_write_8(instance->base + EGA_INDEX_REG, 0x0a);
EGA_INDEX_REG     477 kernel/genarch/src/drivers/ega/ega.c 		pio_write_8(instance->base + EGA_INDEX_REG, 0x0e);
EGA_INDEX_REG     480 kernel/genarch/src/drivers/ega/ega.c 		pio_write_8(instance->base + EGA_INDEX_REG, 0x0f);
EGA_INDEX_REG     489 kernel/genarch/src/drivers/ega/ega.c 		pio_write_8(instance->base + EGA_INDEX_REG, 0x0e);
EGA_INDEX_REG     491 kernel/genarch/src/drivers/ega/ega.c 		pio_write_8(instance->base + EGA_INDEX_REG, 0x0f);
HelenOS homepage, sources at GitHub