Chris O.
Senior Member

I am assuming you don't have this in the setup() { while (!Serial) ; // wait } ;) in case you do I usually stick to this: void setup() { // put your setup code here, to run once: Serial.begin(57600); while...

If you are excellent with soldering perhaps buying the TEENSY 41_NE Without the Ethernet Chip will do it. U6 DP83825 Ethernet transceiver IC LPSPI4 PCS0 - routable to 2 pins GPIO_B0_00 -- GPIO_B1_04 PCS1 -...

This might help a little bit: Teensy 4.1 Schematic

To really understand how all the clocking and dividers are set up I suggest to use this tool: MCUXpresso Config Tools ---- Free download :D After installation you do have to find the correct MCU (MIMXRT1062xxxxB)