Debouncing

components/retro-go/rg_input.c

@@ -196,7 +196,11 @@ bool rg_input_read_gamepad_raw(uint32_t *out)
 
 static void input_task(void *arg)
 {
+#ifdef RG_GAMEPAD_DEBOUNCE_LEVEL
+    const uint8_t debounce_level = RG_GAMEPAD_DEBOUNCE_LEVEL;
+#else
     const uint8_t debounce_level = 0x03;
+#endif
     uint8_t debounce[RG_KEY_COUNT];
     uint32_t local_gamepad_state = 0;
     uint32_t state;
@@ -211,17 +215,17 @@ static void input_task(void *arg)
         {
             for (int i = 0; i < RG_KEY_COUNT; ++i)
             {
+                if (((local_gamepad_state >> i) & 1) == 1) {
+                    if ((debounce[i] == debounce_level && ((state >> i) & 1) == 0) || debounce[i] == 0) {
+                        local_gamepad_state &= ~(1 << i); // Released
+                    }
+                } else {
+                    if ((debounce[i] == 0 && ((state >> i) & 1) == 1) || debounce[i] == debounce_level) {
+                        local_gamepad_state |= (1 << i); // Pressed
+                    }
+                }
                 debounce[i] = ((debounce[i] << 1) | ((state >> i) & 1));
                 debounce[i] &= debounce_level;
-
-                if (debounce[i] == debounce_level) // Pressed
-                {
-                    local_gamepad_state |= (1 << i);
-                }
-                else if (debounce[i] == 0x00) // Released
-                {
-                    local_gamepad_state &= ~(1 << i);
-                }
             }
             gamepad_state = local_gamepad_state;
         }

components/retro-go/targets/byteboi-rev1/config.h

@@ -65,6 +65,9 @@
     {RG_KEY_OPTION, RG_KEY_UP| RG_KEY_SELECT},\
 }
 
+//Try 0x0F or 0x3F with the original switches
+#define RG_GAMEPAD_DEBOUNCE_LEVEL 0x03
+
 // Battery
 #define RG_BATTERY_DRIVER           1
 #define RG_BATTERY_ADC_UNIT         ADC_UNIT_1

components/retro-go/targets/byteboi-rev1/docs/README.md

@@ -23,6 +23,7 @@ Button mapping:
 - Really only supports the first hardware revision. The second revision has a different display and the buttons are connected differently, so it will definitely not work at all with this configuration!
 - No display brightness support (the backlight is connected to the GPIO extender with no PWM support).
 - Low sound quality due to use of internal 8-bit DAC (especially at low volumes).
+- The switches are rather bouncy and somewhat unreliable. I recommend replacing them (e.g. Omron B3F-4050 works very well). Alternatively, you can try to increase the RG_GAMEPAD_DEBOUNCE_LEVEL to 0x0F or 0x3F.
 
 # Images
 ![device.jpg](device.jpg)