--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/components/u8g2/csrc/u8x8_debounce.c Tue Oct 08 12:00:31 2019 +0200
@@ -0,0 +1,205 @@
+/*
+
+ u8x8_debounce.c
+
+ Key/button simple debounce algorithm (Addon for u8x8)
+
+ Universal 8bit Graphics Library (https://github.com/olikraus/u8g2/)
+
+ Copyright (c) 2016, olikraus@gmail.com
+ All rights reserved.
+
+ Redistribution and use in source and binary forms, with or without modification,
+ are permitted provided that the following conditions are met:
+
+ * Redistributions of source code must retain the above copyright notice, this list
+ of conditions and the following disclaimer.
+
+ * Redistributions in binary form must reproduce the above copyright notice, this
+ list of conditions and the following disclaimer in the documentation and/or other
+ materials provided with the distribution.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+ CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
+ CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*/
+
+#include "u8x8.h"
+
+static uint8_t u8x8_read_pin_state(u8x8_t *u8x8)
+{
+ uint8_t i;
+ uint8_t pin_state;
+
+ pin_state = 255; /* be compatible with the setup of the default pin setup, which is 255 */
+ for( i = 0; i < U8X8_PIN_INPUT_CNT; i++ )
+ {
+ pin_state <<= 1;
+
+ /* the callback function should put the return value into this variable */
+ u8x8->gpio_result = 1;
+ u8x8_gpio_call(u8x8, U8X8_MSG_GPIO(i+U8X8_PIN_OUTPUT_CNT), 0);
+ pin_state |= u8x8->gpio_result & 1;
+ }
+
+ return pin_state;
+}
+
+/*
+ return 0 to U8X8_PIN_INPUT_CNT-1 if there is a difference
+ return U8X8_PIN_INPUT_CNT if there is no difference
+*/
+static uint8_t u8x8_find_first_diff(uint8_t a, uint8_t b)
+{
+ uint8_t mask;
+ uint8_t i;
+ mask = 1;
+ i = U8X8_PIN_INPUT_CNT;
+ do
+ {
+ i--;
+ if ( (a & mask) != (b & mask) )
+ return i;
+ mask <<= 1;
+ } while( i > 0 );
+ return U8X8_PIN_INPUT_CNT;
+}
+
+/*
+ State A:
+ u8x8->debounce_last_pin_state == current_state
+ --> State A
+ u8x8->debounce_last_pin_state != current_state
+ --> u8x8->debounce_last_pin_state = current_state
+ --> State B + cnt
+
+ State B + cnt
+ --> state--
+
+ State B
+ u8x8->debounce_last_pin_state == current_state
+ --> keypress detected
+ --> State C
+ u8x8->debounce_last_pin_state != current_state
+ --> State A
+
+ State C
+ u8x8->debounce_last_pin_state == current_state
+ --> State C
+ u8x8->debounce_last_pin_state != current_state
+ --> State A
+
+*/
+
+#ifdef __unix__xxxxxx_THIS_IS_DISABLED
+
+#include <stdio.h>
+#include <stdlib.h>
+uint8_t u8x8_GetMenuEvent(u8x8_t *u8x8)
+{
+ int c;
+ c = getc(stdin);
+ switch(c)
+ {
+ case 'n':
+ return U8X8_MSG_GPIO_MENU_NEXT;
+ case 'p':
+ return U8X8_MSG_GPIO_MENU_PREV;
+ case 's':
+ return U8X8_MSG_GPIO_MENU_SELECT;
+ case 'h':
+ return U8X8_MSG_GPIO_MENU_HOME;
+ case 'x':
+ exit(0);
+ default:
+ puts("press n, p, s, h or x");
+ break;
+ }
+ return 0;
+}
+
+
+#else /* __unix__ */
+
+
+#define U8X8_DEBOUNCE_WAIT 2
+/* do debounce and return a GPIO msg which indicates the event */
+/* returns 0, if there is no event */
+#if defined(__GNUC__) && !defined(__CYGWIN__)
+# pragma weak u8x8_GetMenuEvent
+#endif
+uint8_t u8x8_GetMenuEvent(u8x8_t *u8x8)
+{
+ uint8_t pin_state;
+ uint8_t result_msg = 0; /* invalid message, no event */
+
+ pin_state = u8x8_read_pin_state(u8x8);
+
+ /* States A, B, C & D are encoded in the upper 4 bit*/
+ switch(u8x8->debounce_state)
+ {
+ case 0x00: /* State A, default state */
+ if ( u8x8->debounce_default_pin_state != pin_state )
+ {
+ //u8x8->debounce_last_pin_state = pin_state;
+ u8x8->debounce_state = 0x010 + U8X8_DEBOUNCE_WAIT;
+ }
+ break;
+ case 0x10: /* State B */
+ //if ( u8x8->debounce_last_pin_state != pin_state )
+ if ( u8x8->debounce_default_pin_state == pin_state )
+ {
+ u8x8->debounce_state = 0x00; /* back to state A */
+ }
+ else
+ {
+ /* keypress detected */
+ u8x8->debounce_last_pin_state = pin_state;
+ //result_msg = U8X8_MSG_GPIO_MENU_NEXT;
+ u8x8->debounce_state = 0x020 + U8X8_DEBOUNCE_WAIT; /* got to state C */
+ }
+ break;
+
+ case 0x20: /* State C */
+ if ( u8x8->debounce_last_pin_state != pin_state )
+ {
+ u8x8->debounce_state = 0x00; /* back to state A */
+ }
+ else
+ {
+ u8x8->debounce_state = 0x030; /* got to state D */
+ }
+ break;
+
+ case 0x30: /* State D */
+ /* wait until key release */
+ if ( u8x8->debounce_default_pin_state == pin_state )
+ {
+ u8x8->debounce_state = 0x00; /* back to state A */
+ result_msg = U8X8_MSG_GPIO(u8x8_find_first_diff(u8x8->debounce_default_pin_state, u8x8->debounce_last_pin_state)+U8X8_PIN_OUTPUT_CNT);
+ }
+ else
+ {
+ //result_msg = U8X8_MSG_GPIO_MENU_NEXT;
+ // maybe implement autorepeat here
+ }
+ break;
+ default:
+ u8x8->debounce_state--; /* count down, until there is a valid state */
+ break;
+ }
+ return result_msg;
+}
+
+#endif /* __unix__ */