defragster
Senior Member+
Looking at qtmr_count.ino it is the self same Teensy - so GND is probably good 
There was an issue on timing self same Teensy. I'm running these loops against FreqCount with pin jumpers on one T4:
This gives 23 MHz - which is what other thread Oscope showed:
This bumps up to 30 MHz:
And this drops down to 20 or under 2 when run with lesser delays:
There was an issue on timing self same Teensy. I'm running these loops against FreqCount with pin jumpers on one T4:
This gives 23 MHz - which is what other thread Oscope showed:
Code:
while (1)
{
digitalWriteFast(togPin, !digitalReadFast(togPin) );
}
This bumps up to 30 MHz:
Code:
bool tgl = HIGH;
while (1)
{
digitalWriteFast(togPin, tgl );
tgl = !tgl;
}
And this drops down to 20 or under 2 when run with lesser delays:
Code:
while (1)
{
digitalWriteFast(togPin, LOW);
[URL="https://forum.pjrc.com/threads/54711-Teensy-4-0-First-Beta-Test?p=212280&viewfull=1#post212280"]delayCycles[/URL](220);
digitalWriteFast(togPin, HIGH);
[URL="https://forum.pjrc.com/threads/54711-Teensy-4-0-First-Beta-Test?p=212280&viewfull=1#post212280"]delayCycles[/URL](220);
}