From b3f669843ee2e6b24cbb19b2b5b6d4d6df3d03d2 Mon Sep 17 00:00:00 2001
From: "Dirk O. Kaar" <19971886+dok-net@users.noreply.github.com>
Date: Fri, 27 Sep 2019 11:11:54 +0200
Subject: [PATCH 1/2] Update wiring.c

Cyclically call yield() in delay - compatibility fix for Arduino Scheduler (and similar libs)
Correct understanding of overflow with uint32_t makes for much simpler code.
---
 cores/arduino/wiring.c | 15 ++-------------
 1 file changed, 2 insertions(+), 13 deletions(-)

diff --git a/cores/arduino/wiring.c b/cores/arduino/wiring.c
index a94a9240..5dd6e302 100644
--- a/cores/arduino/wiring.c
+++ b/cores/arduino/wiring.c
@@ -152,18 +152,7 @@ unsigned long micros() {
 void delay(unsigned long ms)
 {
 	uint32_t start_time = micros(), delay_time = 1000*ms;
-
-	/* Calculate future time to return */
-	uint32_t return_time = start_time + delay_time;
-
-	/* If return time overflows */
-	if(return_time < delay_time){
-		/* Wait until micros overflows */
-		while(micros() > return_time);
-	}
-
-	/* Wait until return time */
-	while(micros() < return_time);
+	while(micros() - start_time < delay_time) yield();
 }
 
 /* Delay for the given number of microseconds.  Assumes a 1, 8, 12, 16, 20 or 24 MHz clock. */
@@ -407,4 +396,4 @@ void init()
 	sei();
 }
 
-void setup_timers(void)  __attribute__((weak));
\ No newline at end of file
+void setup_timers(void)  __attribute__((weak));

From acf06add94ee2484348485453a21a0e31f97b8e3 Mon Sep 17 00:00:00 2001
From: "Dirk O. Kaar" <19971886+dok-net@users.noreply.github.com>
Date: Fri, 27 Sep 2019 11:39:02 +0200
Subject: [PATCH 2/2] Update wiring.c

Improved delay() that allows over 49 days delay instead of less than 1.2 hours.
---
 cores/arduino/wiring.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/cores/arduino/wiring.c b/cores/arduino/wiring.c
index 5dd6e302..7a20630e 100644
--- a/cores/arduino/wiring.c
+++ b/cores/arduino/wiring.c
@@ -151,8 +151,13 @@ unsigned long micros() {
 
 void delay(unsigned long ms)
 {
-	uint32_t start_time = micros(), delay_time = 1000*ms;
-	while(micros() - start_time < delay_time) yield();
+	uint32_t start_time = micros();
+
+	while (ms > 0) {
+		while (micros() - start_time < 1000) yield();
+		--ms;
+		start_time += 1000;
+	}
 }
 
 /* Delay for the given number of microseconds.  Assumes a 1, 8, 12, 16, 20 or 24 MHz clock. */