Files
n_signer/firmware/teensy41/blink/blink.ino
T

25 lines
941 B
Arduino

// Teensy 4.1 bring-up: blink the onboard red LED on pin 13 at 1 Hz.
//
// Phase 0 of plans/teensy41_signer_port.md. First sketch to load after the
// board's application flash was erased (board enumerates as Halfkay bootloader
// 16c0:0478 with no /dev/ttyACMx and no LED activity). A successful upload +
// visible 1 Hz blink confirms the toolchain, the FQBN, and the USB upload path.
//
// Build / upload:
// arduino-cli compile --fqbn teensy:avr:teensy41 firmware/teensy41/blink
// arduino-cli upload -p /dev/ttyACM0 --fqbn teensy:avr:teensy41 firmware/teensy41/blink
//
// Exit criterion: the red LED near the USB connector toggles at exactly 1 Hz
// (slower than the PJRC factory blink, which is ~5 Hz, so the change is obvious).
void setup() {
pinMode(LED_BUILTIN, OUTPUT); // LED_BUILTIN == 13 on Teensy 4.1
}
void loop() {
digitalWrite(LED_BUILTIN, HIGH);
delay(500);
digitalWrite(LED_BUILTIN, LOW);
delay(500);
}