After following all advice on board design for a custom Teensy board and using exactly the same parts
used on the teensy, I have trouble getting my Custom Board running.
If I press the PROG button, the Teensy Loader indeed uploads the code, but afterwards the code doesn't
seem to run (LED Blink Example). I have verified the connections and everything seems to be fine.
The only difference in my circuit is that I supply the 3.3V externally from a Bench Power Supply and
that VBUS is not connected (which means only GND, D+, D- are connected).
What I cannot explain: PROG seems to trigger firmware upload, but after code upload no USB device
is being enumerated.
Crystal is 8pF, Inductors are 10uH. VDD = 3.3V
Crystal Symbol looks wrong on the Schematic, but all connections are good.
The Capacitors and the Series Resistor is not assembled on the board.
used on the teensy, I have trouble getting my Custom Board running.
If I press the PROG button, the Teensy Loader indeed uploads the code, but afterwards the code doesn't
seem to run (LED Blink Example). I have verified the connections and everything seems to be fine.
The only difference in my circuit is that I supply the 3.3V externally from a Bench Power Supply and
that VBUS is not connected (which means only GND, D+, D- are connected).
What I cannot explain: PROG seems to trigger firmware upload, but after code upload no USB device
is being enumerated.
Crystal is 8pF, Inductors are 10uH. VDD = 3.3V
Crystal Symbol looks wrong on the Schematic, but all connections are good.
The Capacitors and the Series Resistor is not assembled on the board.
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