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Create src/lib

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Fabien Freling 2018-12-28 17:20:48 +01:00
parent 4cb229e472
commit d3823b9455
11 changed files with 5 additions and 2 deletions
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45
src/timer.ml
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@ -1,45 +0,0 @@
(**
* Copyright (c) 2016, Fabien Freling
* All rights reserved.
*
* This source code is licensed under the BSD 2-clause license found in the
* LICENSE file at the top level directory of this source tree.
*)
let frequence = 4194304
type t = {
clock_rate : int;
period : int;
mutable enabled : bool;
mutable cycles_left : int;
}
let create clock_rate enabled =
let period = frequence / clock_rate in
{
clock_rate;
period;
enabled;
cycles_left = period;
}
(** TIMA - Timer counter *)
let create_tima tac =
let enabled = Bit.is_set tac 2 in
let clock_select = tac land 0b00000011 in
let clock_rate = match clock_select with
| 0 -> 4096
| 1 -> 262144
| 2 -> 65536
| 3 -> 16384
| _ -> failwith "Unreachable clock rate code."
in
create clock_rate enabled
let update timer cycles =
let remain = timer.cycles_left - cycles in
let should_inc = remain <= 0 in
if should_inc then
timer.cycles_left <- remain + timer.period;
should_inc