Add digitalToggleFast for T4.x...

Like what was added for T3.x with that 3 yeard PR, I added the same support to T4.x

Added the PORT TOGGLE defines.  I copied the _PORTSET blocks and then simply used block editing in Sublime text to then change the SET to Toggle.

Also added in the code...

Test sketch:
```
void setup() {
  pinMode(13, OUTPUT);
}

int led = 13;
void loop() {
  digitalToggleFast(led);
  delay(500);
  digitalToggleFast(13);
  delay(250);
  digitalToggle(13);
  delay(1000);
  digitalToggle(led);
  delay(250);
}
```
Also added values to keywords.txt

keywords.txt

@@ -26,6 +26,8 @@ IntervalTimer	KEYWORD2
 printf	KEYWORD2
 digitalWriteFast	KEYWORD2
 digitalReadFast	KEYWORD2
+digitalToggleFast	KEYWORD2
+digitalToggle	KEYWORD2
 transmitterEnable	KEYWORD2
 attachRts	KEYWORD2
 attachCts	KEYWORD2

teensy4/core_pins.h

@@ -263,6 +263,48 @@
 #define CORE_PIN38_PORTCLEAR	GPIO8_DR_CLEAR
 #define CORE_PIN39_PORTCLEAR	GPIO8_DR_CLEAR
 
+#define CORE_PIN0_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN1_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN2_PORTTOGGLE	GPIO9_DR_TOGGLE
+#define CORE_PIN3_PORTTOGGLE	GPIO9_DR_TOGGLE
+#define CORE_PIN4_PORTTOGGLE	GPIO9_DR_TOGGLE
+#define CORE_PIN5_PORTTOGGLE	GPIO9_DR_TOGGLE
+#define CORE_PIN6_PORTTOGGLE	GPIO7_DR_TOGGLE
+#define CORE_PIN7_PORTTOGGLE	GPIO7_DR_TOGGLE
+#define CORE_PIN8_PORTTOGGLE	GPIO7_DR_TOGGLE
+#define CORE_PIN9_PORTTOGGLE	GPIO7_DR_TOGGLE
+#define CORE_PIN10_PORTTOGGLE	GPIO7_DR_TOGGLE
+#define CORE_PIN11_PORTTOGGLE	GPIO7_DR_TOGGLE
+#define CORE_PIN12_PORTTOGGLE	GPIO7_DR_TOGGLE
+#define CORE_PIN13_PORTTOGGLE	GPIO7_DR_TOGGLE
+#define CORE_PIN14_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN15_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN16_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN17_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN18_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN19_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN20_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN21_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN22_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN23_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN24_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN25_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN26_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN27_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN28_PORTTOGGLE	GPIO8_DR_TOGGLE
+#define CORE_PIN29_PORTTOGGLE	GPIO9_DR_TOGGLE
+#define CORE_PIN30_PORTTOGGLE	GPIO8_DR_TOGGLE
+#define CORE_PIN31_PORTTOGGLE	GPIO8_DR_TOGGLE
+#define CORE_PIN32_PORTTOGGLE	GPIO7_DR_TOGGLE
+#define CORE_PIN33_PORTTOGGLE	GPIO9_DR_TOGGLE
+#define CORE_PIN34_PORTTOGGLE	GPIO8_DR_TOGGLE
+#define CORE_PIN35_PORTTOGGLE	GPIO8_DR_TOGGLE
+#define CORE_PIN36_PORTTOGGLE	GPIO8_DR_TOGGLE
+#define CORE_PIN37_PORTTOGGLE	GPIO8_DR_TOGGLE
+#define CORE_PIN38_PORTTOGGLE	GPIO8_DR_TOGGLE
+#define CORE_PIN39_PORTTOGGLE	GPIO8_DR_TOGGLE
+
+
 #define CORE_PIN0_DDRREG	GPIO6_GDIR
 #define CORE_PIN1_DDRREG	GPIO6_GDIR
 #define CORE_PIN2_DDRREG	GPIO9_GDIR
@@ -794,6 +836,62 @@
 #define CORE_PIN53_PORTCLEAR	GPIO9_DR_CLEAR
 #define CORE_PIN54_PORTCLEAR	GPIO9_DR_CLEAR
 
+#define CORE_PIN0_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN1_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN2_PORTTOGGLE	GPIO9_DR_TOGGLE
+#define CORE_PIN3_PORTTOGGLE	GPIO9_DR_TOGGLE
+#define CORE_PIN4_PORTTOGGLE	GPIO9_DR_TOGGLE
+#define CORE_PIN5_PORTTOGGLE	GPIO9_DR_TOGGLE
+#define CORE_PIN6_PORTTOGGLE	GPIO7_DR_TOGGLE
+#define CORE_PIN7_PORTTOGGLE	GPIO7_DR_TOGGLE
+#define CORE_PIN8_PORTTOGGLE	GPIO7_DR_TOGGLE
+#define CORE_PIN9_PORTTOGGLE	GPIO7_DR_TOGGLE
+#define CORE_PIN10_PORTTOGGLE	GPIO7_DR_TOGGLE
+#define CORE_PIN11_PORTTOGGLE	GPIO7_DR_TOGGLE
+#define CORE_PIN12_PORTTOGGLE	GPIO7_DR_TOGGLE
+#define CORE_PIN13_PORTTOGGLE	GPIO7_DR_TOGGLE
+#define CORE_PIN14_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN15_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN16_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN17_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN18_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN19_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN20_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN21_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN22_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN23_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN24_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN25_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN26_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN27_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN28_PORTTOGGLE	GPIO8_DR_TOGGLE
+#define CORE_PIN29_PORTTOGGLE	GPIO9_DR_TOGGLE
+#define CORE_PIN30_PORTTOGGLE	GPIO8_DR_TOGGLE
+#define CORE_PIN31_PORTTOGGLE	GPIO8_DR_TOGGLE
+#define CORE_PIN32_PORTTOGGLE	GPIO7_DR_TOGGLE
+#define CORE_PIN33_PORTTOGGLE	GPIO9_DR_TOGGLE
+#define CORE_PIN34_PORTTOGGLE	GPIO7_DR_TOGGLE
+#define CORE_PIN35_PORTTOGGLE	GPIO7_DR_TOGGLE
+#define CORE_PIN36_PORTTOGGLE	GPIO7_DR_TOGGLE
+#define CORE_PIN37_PORTTOGGLE	GPIO7_DR_TOGGLE
+#define CORE_PIN38_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN39_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN40_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN41_PORTTOGGLE	GPIO6_DR_TOGGLE
+#define CORE_PIN42_PORTTOGGLE	GPIO8_DR_TOGGLE
+#define CORE_PIN43_PORTTOGGLE	GPIO8_DR_TOGGLE
+#define CORE_PIN44_PORTTOGGLE	GPIO8_DR_TOGGLE
+#define CORE_PIN45_PORTTOGGLE	GPIO8_DR_TOGGLE
+#define CORE_PIN46_PORTTOGGLE	GPIO8_DR_TOGGLE
+#define CORE_PIN47_PORTTOGGLE	GPIO8_DR_TOGGLE
+#define CORE_PIN48_PORTTOGGLE	GPIO9_DR_TOGGLE
+#define CORE_PIN49_PORTTOGGLE	GPIO9_DR_TOGGLE
+#define CORE_PIN50_PORTTOGGLE	GPIO9_DR_TOGGLE
+#define CORE_PIN51_PORTTOGGLE	GPIO9_DR_TOGGLE
+#define CORE_PIN52_PORTTOGGLE	GPIO9_DR_TOGGLE
+#define CORE_PIN53_PORTTOGGLE	GPIO9_DR_TOGGLE
+#define CORE_PIN54_PORTTOGGLE	GPIO9_DR_TOGGLE
+
 #define CORE_PIN0_DDRREG	GPIO6_GDIR
 #define CORE_PIN1_DDRREG	GPIO6_GDIR
 #define CORE_PIN2_DDRREG	GPIO9_GDIR
@@ -1489,6 +1587,128 @@ static inline uint8_t digitalReadFast(uint8_t pin)
 	}
 }
 
+void digitalToggle(uint8_t pin);
+static inline void digitalToggleFast(uint8_t pin) __attribute__((always_inline, unused));
+static inline void digitalToggleFast(uint8_t pin)
+{
+	if (__builtin_constant_p(pin)) {
+		if (pin == 0) {
+			CORE_PIN0_PORTTOGGLE = CORE_PIN0_BITMASK;
+		} else if (pin == 1) {
+			CORE_PIN1_PORTTOGGLE = CORE_PIN1_BITMASK;
+		} else if (pin == 2) {
+			CORE_PIN2_PORTTOGGLE = CORE_PIN2_BITMASK;
+		} else if (pin == 3) {
+			CORE_PIN3_PORTTOGGLE = CORE_PIN3_BITMASK;
+		} else if (pin == 4) {
+			CORE_PIN4_PORTTOGGLE = CORE_PIN4_BITMASK;
+		} else if (pin == 5) {
+			CORE_PIN5_PORTTOGGLE = CORE_PIN5_BITMASK;
+		} else if (pin == 6) {
+			CORE_PIN6_PORTTOGGLE = CORE_PIN6_BITMASK;
+		} else if (pin == 7) {
+			CORE_PIN7_PORTTOGGLE = CORE_PIN7_BITMASK;
+		} else if (pin == 8) {
+			CORE_PIN8_PORTTOGGLE = CORE_PIN8_BITMASK;
+		} else if (pin == 9) {
+			CORE_PIN9_PORTTOGGLE = CORE_PIN9_BITMASK;
+		} else if (pin == 10) {
+			CORE_PIN10_PORTTOGGLE = CORE_PIN10_BITMASK;
+		} else if (pin == 11) {
+			CORE_PIN11_PORTTOGGLE = CORE_PIN11_BITMASK;
+		} else if (pin == 12) {
+			CORE_PIN12_PORTTOGGLE = CORE_PIN12_BITMASK;
+		} else if (pin == 13) {
+			CORE_PIN13_PORTTOGGLE = CORE_PIN13_BITMASK;
+		} else if (pin == 14) {
+			CORE_PIN14_PORTTOGGLE = CORE_PIN14_BITMASK;
+		} else if (pin == 15) {
+			CORE_PIN15_PORTTOGGLE = CORE_PIN15_BITMASK;
+		} else if (pin == 16) {
+			CORE_PIN16_PORTTOGGLE = CORE_PIN16_BITMASK;
+		} else if (pin == 17) {
+			CORE_PIN17_PORTTOGGLE = CORE_PIN17_BITMASK;
+		} else if (pin == 18) {
+			CORE_PIN18_PORTTOGGLE = CORE_PIN18_BITMASK;
+		} else if (pin == 19) {
+			CORE_PIN19_PORTTOGGLE = CORE_PIN19_BITMASK;
+		} else if (pin == 20) {
+			CORE_PIN20_PORTTOGGLE = CORE_PIN20_BITMASK;
+		} else if (pin == 21) {
+			CORE_PIN21_PORTTOGGLE = CORE_PIN21_BITMASK;
+		} else if (pin == 22) {
+			CORE_PIN22_PORTTOGGLE = CORE_PIN22_BITMASK;
+		} else if (pin == 23) {
+			CORE_PIN23_PORTTOGGLE = CORE_PIN23_BITMASK;
+		} else if (pin == 24) {
+			CORE_PIN24_PORTTOGGLE = CORE_PIN24_BITMASK;
+		} else if (pin == 25) {
+			CORE_PIN25_PORTTOGGLE = CORE_PIN25_BITMASK;
+		} else if (pin == 26) {
+			CORE_PIN26_PORTTOGGLE = CORE_PIN26_BITMASK;
+		} else if (pin == 27) {
+			CORE_PIN27_PORTTOGGLE = CORE_PIN27_BITMASK;
+		} else if (pin == 28) {
+			CORE_PIN28_PORTTOGGLE = CORE_PIN28_BITMASK;
+		} else if (pin == 29) {
+			CORE_PIN29_PORTTOGGLE = CORE_PIN29_BITMASK;
+		} else if (pin == 30) {
+			CORE_PIN30_PORTTOGGLE = CORE_PIN30_BITMASK;
+		} else if (pin == 31) {
+			CORE_PIN31_PORTTOGGLE = CORE_PIN31_BITMASK;
+		} else if (pin == 32) {
+			CORE_PIN32_PORTTOGGLE = CORE_PIN32_BITMASK;
+		} else if (pin == 33) {
+			CORE_PIN33_PORTTOGGLE = CORE_PIN33_BITMASK;
+		} else if (pin == 34) {
+			CORE_PIN34_PORTTOGGLE = CORE_PIN34_BITMASK;
+		} else if (pin == 35) {
+			CORE_PIN35_PORTTOGGLE = CORE_PIN35_BITMASK;
+		} else if (pin == 36) {
+			CORE_PIN36_PORTTOGGLE = CORE_PIN36_BITMASK;
+		} else if (pin == 37) {
+			CORE_PIN37_PORTTOGGLE = CORE_PIN37_BITMASK;
+		} else if (pin == 38) {
+			CORE_PIN38_PORTTOGGLE = CORE_PIN38_BITMASK;
+		} else if (pin == 39) {
+			CORE_PIN39_PORTTOGGLE = CORE_PIN39_BITMASK;
+#if CORE_NUM_DIGITAL >= 55
+		} else if (pin == 40) {
+			CORE_PIN40_PORTTOGGLE = CORE_PIN40_BITMASK;
+		} else if (pin == 41) {
+			CORE_PIN41_PORTTOGGLE = CORE_PIN41_BITMASK;
+		} else if (pin == 42) {
+			CORE_PIN42_PORTTOGGLE = CORE_PIN42_BITMASK;
+		} else if (pin == 43) {
+			CORE_PIN43_PORTTOGGLE = CORE_PIN43_BITMASK;
+		} else if (pin == 44) {
+			CORE_PIN44_PORTTOGGLE = CORE_PIN44_BITMASK;
+		} else if (pin == 45) {
+			CORE_PIN45_PORTTOGGLE = CORE_PIN45_BITMASK;
+		} else if (pin == 46) {
+			CORE_PIN46_PORTTOGGLE = CORE_PIN46_BITMASK;
+		} else if (pin == 47) {
+			CORE_PIN47_PORTTOGGLE = CORE_PIN47_BITMASK;
+		} else if (pin == 48) {
+			CORE_PIN48_PORTTOGGLE = CORE_PIN48_BITMASK;
+		} else if (pin == 49) {
+			CORE_PIN49_PORTTOGGLE = CORE_PIN49_BITMASK;
+		} else if (pin == 50) {
+			CORE_PIN50_PORTTOGGLE = CORE_PIN50_BITMASK;
+		} else if (pin == 51) {
+			CORE_PIN51_PORTTOGGLE = CORE_PIN51_BITMASK;
+		} else if (pin == 52) {
+			CORE_PIN52_PORTTOGGLE = CORE_PIN52_BITMASK;
+		} else if (pin == 53) {
+			CORE_PIN53_PORTTOGGLE = CORE_PIN53_BITMASK;
+		} else if (pin == 54) {
+			CORE_PIN54_PORTTOGGLE = CORE_PIN54_BITMASK;
+		}
+#endif
+	} else {
+		digitalToggle(pin);
+	}
+}
 
 void pinMode(uint8_t pin, uint8_t mode);
 void init_pins(void);

teensy4/digital.c

@@ -108,6 +108,17 @@ void digitalWrite(uint8_t pin, uint8_t val)
 	}
 }
 
+void digitalToggle(uint8_t pin)
+{
+	const struct digital_pin_bitband_and_config_table_struct *p;
+	uint32_t pinmode, mask;
+
+	if (pin >= CORE_NUM_DIGITAL) return;
+	p = digital_pin_to_info_PGM + pin;
+	mask = p->mask;
+	*(p->reg + 0x23) = mask; // toggle register
+}
+
 uint8_t digitalRead(uint8_t pin)
 {
 	const struct digital_pin_bitband_and_config_table_struct *p;