Arduino Zero D0/D1 set output high

Question

I am trying to use D0/D1 as normal IO pins but DigitalWrite does not work as on an Arduino UNO.

I know the SAMD21G has SERCOM but I can't seem to find an example of not using D0/D1 as an UART port.

EDIT ** Code I have tried:

#define MYMASK 0x00000C00
void setup() {
 REG_PORT_DIRSET0 = MYMASK; // Direction set to OUTPUT
 REG_PORT_OUTSET0 = MYMASK; // set state of pin(s) to TRUE (HIGH)
 delay(1000);
 REG_PORT_OUTCLR0 = MYMASK; // set state of pin(s) to FALSE (LOW) 
}
void loop() {
}

Answer 1

You can do this by simply calling the right registers:

Example 1, using a MASK

D0/D1 are mapped to to PA10 & PA11 on the M0

/* The following ports where selected
 PORT_PA11
 PORT_PA10
 */ 
#define MYMASK 0x00000C00
int main (void)
{
 system_init();
 REG_PORT_DIRSET0 = MYMASK; // Direction set to OUTPUT
 REG_PORT_OUTSET0 = MYMASK; // set state of pin(s) to TRUE (HIGH)
 //REG_PORT_OUTCLR0 = MYMASK; // set state of pin(s) to FALSE (LOW)
 while(1){ 
 } 
}

Here is another simple example:

/* The following ports where selected
 PORT_PA11
 PORT_PA10
 */ 
#define MYMASK 0x00000C00
#define LED1 PORT_PA10
#define LED2 PORT_PA11
int main (void)
{
 system_init();
 REG_PORT_DIRSET0 = LED1 | LED2; // Direction set to OUTPUT
 REG_PORT_OUTSET0 = LED1 | LED2; // set state of pin(s) to TRUE (HIGH)
 //REG_PORT_OUTCLR0 = LED1 | LED2; // set state of pin(s) to FALSE (LOW)
 while(1){ 
 } 
}

In the Arduino IDE you can do something like:

#define MYMASK 0x00000C00
void setup() {
 REG_PORT_DIRSET0 = MYMASK; // Direction set to OUTPUT 
}
void loop() {
 REG_PORT_OUTSET0 = MYMASK; // set state of pin(s) to TRUE (HIGH)
 delay(1000);
 REG_PORT_OUTCLR0 = MYMASK; // set state of pin(s) to FALSE (LOW) 
 delay(1000);
}

• Bertus Kruger: Thanks for the quick reply... I tried the the above trough Arduino but without any luck. I wonder if Arduino overwrites the registers in the background.
• PhillyNJ: Can't tell unless you post your code.
• Bertus Kruger: Have added the Arduino Code...
• PhillyNJ: @BertusKruger - I just tried the code on my Arduino M0 which has D0/D1 mapped to PA11 & PA12. You have set the ports to low before the loop. See my revised code.
• PhillyNJ: edit - D0/D1 are mapped to PA10 & PA11