add an example

Fix the `ocamlwiring_pull_up_dn_control` stub

_oasis

@@ -9,7 +9,12 @@ Plugins:     META (0.4), DevFiles (0.4)
 Library "WiringPi"
   Path:       src/
   BuildTools: ocamlbuild
-  Modules:    WiringPi
+  Modules:    WiringPi, Gpio3
   CSources:   WiringPi_stubs.c
   CCLib:      -lwiringPi
-  
+
+Executable "wpi-button-example"
+  Path:         examples/
+  BuildTools:   ocamlbuild
+  MainIs:       button.ml
+  BuildDepends: WiringPi,unix

examples/button.ml

@@ -0,0 +1,22 @@
+open Gpio3
+
+(* Set up the pins the following way: *)
+(* pin 3 (pull-up) -> btn -> resistor -> gnd *)
+
+let setup () =
+  Gpio3.setup ();
+  pin_mode GPIO3 IN;
+  pull_up_dn_control GPIO3 UP
+
+let rec loop () =
+  (match digital_read GPIO3 with
+   | LOW -> print_endline "-- LOW"
+   | HIGH -> print_endline "++ HIGH");
+  Unix.sleepf 0.5;
+  loop ()
+
+
+let _ =
+  setup ();
+  loop ();
+

src/Gpio3.ml

@@ -0,0 +1,95 @@
+(** Typed interface for WiritngPi.
+ Missing:
+ - modes PWM_OUTPUT and GPIO_GLOCK
+ - pwm_write
+ - digital_write_byte
+ - analog_read
+ - analog_write
+ - delay, delay_microseconds (?)
+ *)
+open WiringPi
+
+let setup () = ignore (setup_gpio ())
+
+type pin =
+ (*  3V3  |  5V   *)
+    GPIO2 | (* 5V *)
+    GPIO3 | (* GND *)
+    GPIO4 | GPIO14
+(* GND *) | GPIO15 |
+   GPIO17 | GPIO18 |
+   GPIO27 | (* GND *)
+   GPIO22 | GPIO23
+(* 3V3 *) | GPIO24 |
+   GPIO10 | (* GND *)
+    GPIO9 | GPIO25 |
+   GPIO11 | GPIO8 
+(* GND *) | GPIO7  |
+    GPIO0 | GPIO1  |
+    GPIO5 | (* GND *)
+    GPIO6 | GPIO12 |
+   GPIO13 | (* GND *)
+   GPIO19 | GPIO16 |
+   GPIO26 | GPIO20
+
+let int_of_pin = function
+  | GPIO2 -> 2
+  | GPIO3 -> 3
+  | GPIO4 -> 4
+  | GPIO14 -> 14
+  | GPIO15 -> 15
+  | GPIO17 -> 17
+  | GPIO18 -> 18
+  | GPIO27 -> 27
+  | GPIO22 -> 22
+  | GPIO23 -> 23
+  | GPIO24 -> 24
+  | GPIO10 -> 10
+  | GPIO9 -> 9
+  | GPIO25 -> 25
+  | GPIO11 -> 11
+  | GPIO8 -> 8
+  | GPIO7 -> 7
+  | GPIO0 -> 0
+  | GPIO1 -> 1
+  | GPIO5 -> 5
+  | GPIO6 -> 6
+  | GPIO12 -> 12
+  | GPIO13 -> 13
+  | GPIO19 -> 19
+  | GPIO16 -> 16
+  | GPIO26 -> 26
+  | GPIO20 -> 20
+
+(* What is not supported: PWM_OUTPUT and GPIO_GLOCK *)
+type mode = IN | OUT
+
+(** [pin_mode] sets the mode of the pin to either input or output
+   (other modes not supported at this moment). *)
+let pin_mode (p : pin) (m : mode) =
+  match m with
+  | IN -> WiringPi.pin_mode (int_of_pin p) 0
+  | OUT -> WiringPi.pin_mode (int_of_pin p) 1
+
+type pin_updn = UP | DOWN | OFF
+
+(** [pull_up_dn_control] sets the pull-up or pull-down resistor mode on
+   the given pin, which should be set as an input. *)
+let pull_up_dn_control (p : pin) = function
+  | UP -> WiringPi.pull_up_dn_control (int_of_pin p) 2
+  | DOWN -> WiringPi.pull_up_dn_control (int_of_pin p) 1
+  | OFF -> WiringPi.pull_up_dn_control (int_of_pin p) 0
+
+type pin_value = LOW | HIGH
+
+(** [digital_write] the value HIGH or LOW to the given pin which must
+   have been previously set as an output. *)
+let digital_write (p : pin) (v : pin_value) =
+  match v with
+  | LOW -> WiringPi.digital_write (int_of_pin p) 0
+  | HIGH -> WiringPi.digital_write (int_of_pin p) 1
+
+let digital_read (p : pin) : pin_value =
+  match WiringPi.digital_read (int_of_pin p) with
+  | 0 -> LOW
+  | _ -> HIGH

src/Gpio3.mli

@@ -0,0 +1,33 @@
+(** broadcom numbers *)
+val setup : unit -> unit
+
+type pin =
+ (*  3V3  |  5V   *)
+    GPIO2 | (* 5V *)
+    GPIO3 | (* GND *)
+    GPIO4 | GPIO14
+(* GND *) | GPIO15 |
+   GPIO17 | GPIO18 |
+   GPIO27 | (* GND *)
+   GPIO22 | GPIO23
+(* 3V3 *) | GPIO24 |
+   GPIO10 | (* GND *)
+    GPIO9 | GPIO25 |
+   GPIO11 | GPIO8 
+(* GND *) | GPIO7  |
+    GPIO0 | GPIO1  |
+    GPIO5 | (* GND *)
+    GPIO6 | GPIO12 |
+   GPIO13 | (* GND *)
+   GPIO19 | GPIO16 |
+   GPIO26 | GPIO20
+
+type pin_value = LOW | HIGH
+
+type mode = IN | OUT
+type pin_updn = UP | DOWN | OFF
+               
+val pin_mode : pin -> mode -> unit
+val pull_up_dn_control : pin -> pin_updn -> unit
+val digital_write : pin -> pin_value -> unit
+val digital_read : pin -> pin_value

src/WiringPi.ml

@@ -1,55 +1,55 @@
 (** This module is useful to communicate with the GPIO ports of a Raspberry Pi.
     It uses the WiringPi library: http://wiringpi.com/ **)
 
-(* Test function *)
-external test_hello_world : unit -> unit = "caml_hello"
-
 (* Use it at the very beginning to choose the numeroting mode *)
-external setup : unit -> int = "caml_wiringPiSetup"
-external setupGio : unit -> int = "caml_wiringPiSetupGpio"
-external setupPhys : unit -> int = "caml_wiringPiSetupPhys"
-external setupSys : unit -> int = "caml_wiringPiSetupSys"
+external setup: unit -> int = "ocamlwiring_setup"
+external setup_gpio: unit -> int = "ocamlwiring_setup_gpio"
+external setup_phys: unit -> int = "ocamlwiring_setup_phys"
+external setup_sys: unit -> int = "ocamlwiring_setup_sys"
 
 (* ##########  Write on the device ########## *)
 (* This sets the mode of a pin to either INPUT (= 0), OUTPUT (= 1),
  * PWM_OUTPUT (= 2) or GPIO_CLOCK (= 3).
  * Note that only wiringPi pin 1 (BCM_GPIO 18) supports PWM output and only
  * wiringPi pin 7 (BCM_GPIO 4) supports CLOCK output modes. *)
-external pinMode : int -> int -> unit = "caml_pinMode"
-    
+external pin_mode: int -> int -> unit = "ocamlwiring_pin_mode"
+
 (* This sets the pull-up or pull-down resistor mode on the given pin, which
  * should be set as an input. *)
-external pullUpDnControl : int -> int -> unit = "caml_pullUpDnControl"
-    
+external pull_up_dn_control: int -> int -> unit = "ocamlwiring_pull_up_dn_control"
+
 (* Writes the value HIGH or LOW (1 or 0) to the given pin which must have
  * been previously set as an output. *)
-external digitalWrite : int -> int -> unit = "caml_digitalWrite"
-    
+external digital_write: int -> int -> unit = "ocamlwiring_digital_write"
+
 (* Writes the value to the PWM register for the given pin.
  * The Raspberry Pi has one on-board PWM pin, pin 1 (BMC_GPIO 18, Phys 12) and
  * the range is 0-1024. Other PWM devices may have other PWM ranges *)
-external pwmWrite : int -> int -> unit = "caml_pwmWrite"
+external pwm_write: int -> int -> unit = "ocamlwiring_pwm_write"
 
 (* This function returns the value read at the given pin. It will be HIGH
  * or LOW (1 or 0) depending on the logic level at the pin. *)
-external digitalRead : int -> int = "caml_digitalRead"
-external digitalWriteByte : int -> unit = "caml_digitalWriteByte"
+external digital_read: int -> int = "ocamlwiring_digital_read"
+external digital_write_byte: int -> unit = "ocamlwiring_digital_write_byte"
+
+external analog_read: int -> int = "ocamlwiring_analog_read"
+external analog_write: int -> int -> unit = "ocamlwiring_analog_write"
+
 
-    
 (* ##########  Timing ########## *)
 (* Use it to wait a few ms or µs. If you want to wait for several
    secondes, use Unix.sleep. *)
 (* wait n ms *)
-external delay : int -> unit = "caml_delay"
+external delay: int -> unit = "ocamlwiring_delay"
 (* wait n µs *)
-external delayMicroseconds : int -> unit = "caml_delayMicroseconds"
-    
+external delay_microseconds: int -> unit = "ocamlwiring_delay_microseconds"
+
 (* This returns a number representing the number if ms/µs since your program
  * called one of the wiringPiSetup functions. *)
-external millis : unit -> int = "caml_millis"
-external micros : unit -> int = "caml_micros"
+external millis : unit -> int = "ocamlwiring_millis"
+external micros : unit -> int = "ocamlwiring_micros"
+
 
-    
 (* ################# Name of pins : ################# *)
 (* +----------+-Rev2-+------+--------+------+-------+ *)
 (* | wiringPi | GPIO | Phys | Name   | Mode | Value | *)

src/WiringPi_stubs.c

@@ -9,32 +9,25 @@
 #include <wiringPi.h>
 #include <wiringShift.h>
 
-value caml_hello(value unit)
-{
-  CAMLparam1(unit);
-  printf("Hello world!\n");
-  CAMLreturn(Val_unit);
-}
-
-value caml_wiringPiSetup(value unit)
+value ocamlwiring_setup(value unit)
 {
   CAMLparam1(unit);
   CAMLreturn(Val_int(wiringPiSetup()));
 }
 
-value caml_wiringPiSetupGpio(value unit)
+value ocamlwiring_setup_gpio(value unit)
 {
   CAMLparam1(unit);
   CAMLreturn(Val_int(wiringPiSetupGpio()));
 }
 
-value caml_wiringPiSetupPhys(value unit)
+value ocamlwiring_setup_phys(value unit)
 {
   CAMLparam1(unit);
   CAMLreturn(Val_int(wiringPiSetupPhys()));
 }
 
-value caml_wiringPiSetupSys(value unit)
+value ocamlwiring_setup_sys(value unit)
 {
   CAMLparam1(unit);
   CAMLreturn(Val_int(wiringPiSetupSys()));
@@ -42,45 +35,56 @@ value caml_wiringPiSetupSys(value unit)
 
 // Core functions
 
-value caml_pinMode(value pin, value mode)
+value ocamlwiring_pin_mode(value pin, value mode)
 {
   CAMLparam2(pin, mode);
   pinMode(Int_val(pin), Int_val(mode));
   CAMLreturn(Val_unit);
 }
 
-value caml_pullUpDnControl(value pin, value pud)
+value ocamlwiring_pull_up_dn_control(value pin, value pud)
 {
   CAMLparam2(pin, pud);
-  pullUpDnControl(Int_val(pin), Int_val(pin));
+  pullUpDnControl(Int_val(pin), Int_val(pud));
   CAMLreturn(Val_unit);
 }
 
-value caml_digitalWrite(value pin, value value_p)
+value ocamlwiring_digital_write(value pin, value value_p)
 {
   CAMLparam2(pin, value_p);
   digitalWrite(Int_val(pin), Int_val(value_p));
   CAMLreturn(Val_unit);
 }
 
-value caml_pwmWrite(value pin, value value_p)
+value ocamlwiring_pwm_write(value pin, value value_p)
 {
   CAMLparam2(pin, value_p);
   pwmWrite(Int_val(pin), Int_val(value_p));
   CAMLreturn(Val_unit);
 }
 
-value caml_digitalRead(value pin)
+value ocamlwiring_digital_read(value pin)
 {
   CAMLparam1(pin);
   CAMLreturn(Val_int(digitalRead(Int_val(pin))));
 }
 
-// AnalogRead and AnalogWrite needs to be added (module must be added)
+value ocamlwiring_analog_read(value pin)
+{
+  CAMLparam1(pin);
+  CAMLreturn(Val_int(analogRead(Int_val(pin))));
+}
+
+value ocamlwiring_analog_write(value pin, value value_p)
+{
+  CAMLparam2(pin, value_p);
+  analogWrite(Int_val(pin), Int_val(value_p));
+  CAMLreturn(Val_unit);
+}
 
 // Raspberry Pi Specifics
 
-value caml_digitalWriteByte(value value_p)
+value ocamlwiring_digital_write_byte(value value_p)
 {
   CAMLparam1(value_p);
   digitalWriteByte(Int_val(value_p));
@@ -95,7 +99,7 @@ value caml_digitalWriteByte(value value_p)
 
 /* This returns a number representing the number if milliseconds since your
  * program called one of the wiringPiSetup functions. */
-value caml_millis(value unit)
+value ocamlwiring_millis(value unit)
 {
   CAMLparam1(unit);
   CAMLreturn(Val_int(millis()));
@@ -103,7 +107,7 @@ value caml_millis(value unit)
 
 /* This returns a number representing the number of microseconds since your
  * program called one of the wiringPiSetup functions. */
-value caml_micros(value unit)
+value ocamlwiring_micros(value unit)
 {
   CAMLparam1(unit);
   CAMLreturn(Val_int(micros()));
@@ -111,10 +115,10 @@ value caml_micros(value unit)
 
 /* This causes program execution to pause for at least howLong milliseconds.
  * Due to the multi-tasking nature of Linux it could be longer. */
-value caml_delay(value howLong)
+value ocamlwiring_delay(value how_long)
 {
-  CAMLparam1(howLong);
-  delay(Int_val(howLong));
+  CAMLparam1(how_long);
+  delay(Int_val(how_long));
   CAMLreturn(Val_unit);
 }
 
@@ -125,9 +129,9 @@ value caml_delay(value howLong)
  * nanosleep() function – You may need to consider the implications of very
  * short delays on the overall performance of the system, especially if using
  * threads. */
-value caml_delayMicroseconds(value howLong)
+value ocamlwiring_delay_microseconds(value how_long)
 {
-  CAMLparam1(howLong);
-  delayMicroseconds(Int_val(howLong));
+  CAMLparam1(how_long);
+  delayMicroseconds(Int_val(how_long));
   CAMLreturn(Val_unit);
 }