From f2c3c778a752532cf973e052d5660a30da88b16e Mon Sep 17 00:00:00 2001
From: Fabian Felix Selbach <ffs2309.fs@gmail.com>
Date: Fri, 1 Mar 2024 20:29:54 +0100
Subject: [PATCH] Added proper debouncing

---
 Readme.md    |  3 ++-
 kbdrv-main.c | 17 +++++++++++------
 2 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/Readme.md b/Readme.md
index 200ef5f..857e64d 100644
--- a/Readme.md
+++ b/Readme.md
@@ -7,6 +7,7 @@ A keyboard software meant to run on a Milk-V duo.
 - [x] (partial) LED support
 - [x] N-Key rollover (The currently included hid descriptor "only" supports 80 key rollover but adapting to more keys would be fairly trivial)
 - [x] Multiple bindings per key
+- [x] Debouncing (immediate on, 5ms until key turns off)
 ### Todo
 - [ ] RGB
 - [ ] Layer support
@@ -17,7 +18,7 @@ This file contains all the program code required to scan the keyboard matrix as
 
 ### keyboard\_mapping.h
 This file contains all the configuration and mapping of the device you are working with. This includes the GPIO pin mapping to rows/columns, matrix to binding
-identifier and binding identifier to hid-modifiers/hid-usage codes. Currently there is no support for binding multiple actions to one key.
+identifier and binding identifier to hid-modifiers/hid-usage codes.
 
 ## Important notes
 
diff --git a/kbdrv-main.c b/kbdrv-main.c
index a4dbd99..c2f37d0 100644
--- a/kbdrv-main.c
+++ b/kbdrv-main.c
@@ -10,7 +10,7 @@
 
 #include <wiringx.h>
 
-bool state[sizeof(columns)/sizeof(int)][sizeof(rows)/sizeof(int)];
+bool state[sizeof(columns)/sizeof(int)][sizeof(rows)/sizeof(int)][5];
 #define BUF_LEN 512
 int main() {
 	
@@ -56,7 +56,8 @@ int main() {
 		perror(filename);
 		return 3;
 	}
-
+	
+	int dbIndex = 4; //db = debounce! -> debounceIndex
 	while(true){
 		FD_ZERO(&rfds);
 		FD_SET(fd, &rfds);
@@ -85,9 +86,11 @@ int main() {
 		for(int c = 0; c < sizeof(columns)/sizeof(int); c++){
 			digitalWrite(columns[c], LOW);
 			for(int r = 0; r < sizeof(rows)/sizeof(int); r++){
-				char curState = state[c][r];
-				state[c][r] = (digitalRead(rows[r]) == LOW);
-				if((state[c][r] == true || curState == true)){
+				bool curState = state[c][r][(dbIndex+1)%5];
+				state[c][r][dbIndex] = (digitalRead(rows[r]) == LOW);
+				if((state[c][r][dbIndex] == true || state[c][r][(dbIndex+1)%5] == true || state[c][r][(dbIndex+2)%5] == true
+							|| state[c][r][(dbIndex+3)%5] == true || state[c][r][(dbIndex+4)%5] == true)){
+
 					char bind[sizeof(mapping[c][r])/sizeof(char)];
 					strcpy(bind, mapping[c][r]);
 					char *binding = strtok(bind, " ");
@@ -106,10 +109,12 @@ int main() {
 						}
 					}
 				}
-				//if(state[c][r] != curState) printf("statechange to %s column %d, row %d\n", (state[c][r] ? "HIGH" : "LOW"), c, r);
+				//if(state[c][r][dbIndex] != curState) printf("statechange to %s column %d, row %d\n", (state[c][r] ? "HIGH" : "LOW"), c, r);
 			}
 			digitalWrite(columns[c], HIGH);
 		}
+		dbIndex--;
+		if(dbIndex > 0) dbIndex = 4;
 		write(fd, report, 82);//Send Report over USB
 		usleep(700);
 	}