41 lines
1.3 KiB
OCaml
41 lines
1.3 KiB
OCaml
(** This module allow to communicate with a shift-register **)
|
|
|
|
(* Source :
|
|
- http://blog.idleman.fr/raspberry-pi-20-creer-un-tableau-de-bord-connect-au-net/
|
|
- http://www.onsemi.com/pub_link/Collateral/MC74HC595A-D.PDF
|
|
*)
|
|
open WiringPiOcaml
|
|
(** reg : (pin_value = p_v, pin_shift = p_s, pin_apply = p_a). It is
|
|
used to contain the needed input **)
|
|
type reg = int * int * int;;
|
|
|
|
(** The first thing to do is setupPhys (). This function put in OUTPUT
|
|
mode the outputs and return back a bool array which represent the output of registers (begining with the first LED of the first shift register) **)
|
|
let initRegister ?nb_reg:(nb_reg = 1) reg =
|
|
let (p_v, p_s, p_a) = reg in
|
|
pinMode p_v 1; (* mode output *)
|
|
pinMode p_s 1;
|
|
pinMode p_a 1;
|
|
Array.make (8*nb_reg) false (* return back an array for all pieces *)
|
|
|
|
let write pin value = digitalWrite pin (if value then 1 else 0)
|
|
|
|
(** This function apply all modifications to the register **)
|
|
let applyReg reg leds =
|
|
let (p_v, p_s, p_a) = reg in
|
|
write p_a false;
|
|
for i = (Array.length leds) - 1 downto 0 do
|
|
write p_s false;
|
|
write p_v leds.(i);
|
|
write p_s true;
|
|
done;
|
|
write p_a true
|
|
|
|
|
|
(** Don't forget to apply it with applyReg after **)
|
|
let clearLeds leds =
|
|
Array.iteri (fun i x -> (leds.(i) <- false)) leds
|
|
let lightLeds leds =
|
|
Array.iteri (fun i x -> (leds.(i) <- true)) leds
|
|
|