More accurate delay() function from BenF.

Rocketct · sandeepmistry · commit 3b6466b5e6dd · 2018-12-13T10:33:06.000-05:00
porting of arduino/ArduinoCore-avr@67c0a19#diff-ab397febf179e1982f4ee0758df4c982
diff --git a/cores/arduino/delay.c b/cores/arduino/delay.c
@@ -63,17 +63,22 @@ unsigned long micros( void )
 
 void delay( unsigned long ms )
 {
-  if ( ms == 0 )
+  if (ms == 0)
   {
-    return ;
+    return;
   }
 
-  uint32_t start = _ulTickCount ;
+  uint32_t start = micros();
 
-  do
+  while (ms > 0)
   {
-    yield() ;
-  } while ( _ulTickCount - start < ms ) ;
+    yield();
+    while (ms > 0 && (micros() - start) >= 1000)
+    {
+      ms--;
+      start += 1000;
+    }
+  }
 }
 
 #include "Reset.h" // for tickReset()

Original file line number	Diff line number	Diff line change
`@@ -63,17 +63,22 @@ unsigned long micros( void )`
`63`	`63`
`64`	`64`	`void delay( unsigned long ms )`
`65`	`65`	`{`
`66`		`- if ( ms == 0 )`
	`66`	`+ if (ms == 0)`
`67`	`67`	`{`
`68`		`- return ;`
	`68`	`+ return;`
`69`	`69`	`}`
`70`	`70`
`71`		`- uint32_t start = _ulTickCount ;`
	`71`	`+ uint32_t start = micros();`
`72`	`72`
`73`		`- do`
	`73`	`+ while (ms > 0)`
`74`	`74`	`{`
`75`		`- yield() ;`
`76`		`- } while ( _ulTickCount - start < ms ) ;`
	`75`	`+ yield();`
	`76`	`+ while (ms > 0 && (micros() - start) >= 1000)`
	`77`	`+ {`
	`78`	`+ ms--;`
	`79`	`+ start += 1000;`
	`80`	`+ }`
	`81`	`+ }`
`77`	`82`	`}`
`78`	`83`
`79`	`84`	`#include "Reset.h" // for tickReset()`