From 224aa2fac9a5ce187e5029d81bcd21c534b0de9f Mon Sep 17 00:00:00 2001
From: "Hansi, dl9rdz" <dl9rdz@darc.de>
Date: Sun, 26 Sep 2021 20:09:57 +0200
Subject: [PATCH] spurious IRQ workaround. probably related to ESP32 errata
 3.14
 https://www.espressif.com/sites/default/files/documentation/eco_and_workarounds_for_bugs_in_esp32_en.pdf

---
 RX_FSK/RX_FSK.ino | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/RX_FSK/RX_FSK.ino b/RX_FSK/RX_FSK.ino
index a9b5e4c..d21ec86 100644
--- a/RX_FSK/RX_FSK.ino
+++ b/RX_FSK/RX_FSK.ino
@@ -1896,8 +1896,10 @@ void checkTouchStatus() {
 }
 
 unsigned long bdd1, bdd2;
+static bool b1wasdown = false;
 void IRAM_ATTR buttonISR() {
   if (digitalRead(button1.pin) == 0) { // Button down
+    b1wasdown = true;
     unsigned long now = my_millis();
     if (now - button1.keydownTime < 500) {
       // Double press
@@ -1910,6 +1912,8 @@ void IRAM_ATTR buttonISR() {
     button1.numberKeyPresses += 1;
     button1.keydownTime = now;
   } else { //Button up
+    if(!b1wasdown) return;
+    b1wasdown = false;
     unsigned long now = my_millis();
     if (button1.doublepress == -1) return;   // key was never pressed before, ignore button up
     unsigned int elapsed = now - button1.keydownTime;
@@ -1967,7 +1971,7 @@ int getKeyPress() {
   button1.pressed = KP_NONE;
 #if 0
   int x = digitalRead(button1.pin);
-  Serial.printf("Debug: bdd1=%ld, bdd2=%ld\b", bdd1, bdd2);
+  Serial.printf("Debug: bdd1=%ld, bdd2=%ld\n", bdd1, bdd2);
   Serial.printf("button1 press (dbl:%d) (now:%d): %d at %ld (%d)\n", button1.doublepress, x, p, button1.keydownTime, button1.numberKeyPresses);
 #endif
   return p;