brianmichalk
Active member
I've used the T3.2 for years, and this is a strange problem that should be beneath me, but I can't figure it out.
Teensy 3.5.
Arduino IDE 1.8.9
Teensy Loader 1.46
Code:
I am unable to get reliable serial data. The LED is flashing, and I must power cycle multiple times until the USB serial connection is reliable. kernel messages seem normal for the USB negotiation. The first cat of the port gives me a buffer full, then the next cat hangs waiting for more data. Miniterm gives the same result.
Update:
If I use the Arduino serial monitor, it's initially grey, then when the Teensy boots, it shows the serial data. I can close the Arduino serial monitor, and open miniterm, or cat the device, and it functions as expected.
If I replug the Teensy without the serial monitor running, Miniterm, or cat do not work. It seems there's some handshake that's happening when the program first starts, and the serial monitor is allowing it to work properly. How can I get this to work without the serial monitor?
Teensy 3.5.
Arduino IDE 1.8.9
Teensy Loader 1.46
Code:
Code:
void setup() {
Serial.begin(57600);
pinMode(LED_BUILTIN, OUTPUT);
}
void loop() {
delay(1000);
Serial.print("Hello ");
Serial.println(millis());
digitalWrite(LED_BUILTIN, !digitalRead(LED_BUILTIN));
}
I am unable to get reliable serial data. The LED is flashing, and I must power cycle multiple times until the USB serial connection is reliable. kernel messages seem normal for the USB negotiation. The first cat of the port gives me a buffer full, then the next cat hangs waiting for more data. Miniterm gives the same result.
Code:
root@michalk-desktop:~# cat /dev/ttyACM0
Hello 1300
Hello 2300
Hello 3300
Hello 4300
Hello 5300
Hello 6300
Hello 7300
Hello 8300
Hello 9300
Hello 10300
^C
root@michalk-desktop:~# cat /dev/ttyACM0
^C
root@michalk-desktop:~# cat /dev/ttyACM0
Update:
If I use the Arduino serial monitor, it's initially grey, then when the Teensy boots, it shows the serial data. I can close the Arduino serial monitor, and open miniterm, or cat the device, and it functions as expected.
If I replug the Teensy without the serial monitor running, Miniterm, or cat do not work. It seems there's some handshake that's happening when the program first starts, and the serial monitor is allowing it to work properly. How can I get this to work without the serial monitor?
Last edited: