lesson 20, preliminar

20-interrupts-timer/README.md

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+
+Everything is now ready to test our hardware interrupts.
+
+Timer
+-----
+
+The timer is easy to configure. First we'll declare an `init_timer()` on `cpu/timer.h` and
+implement it on `cpu/timer.c`. It is just a matter of computing the clock frequency and
+sending the bytes to the appropriate ports.
+
+## se printa gibberish, pq? mirar primero si se arregla con un kprint_int
+## yo tenia una funcion que printaba enteros??!!! pero al rever. hacerla ahora bien y
+## en el proximo episodio limpiar codigo y crear una libc
+
+
+Finally, go back to the `kernel/kernel.c` and do two things. Enable interrupts again
+(very important!) and then initialize the timer interrupt.
+
+Go `make run` and you'll see the clock ticking! Unfortunately we are not printing the correct values
+on screen, so we'll go ahead to `drivers/screen.c` and add a new `kprint_int()` method, also declaring
+it on `drivers/screen.h`