Very odd behavior of Serial stream

[johnwasser]

@alexblade

    uint8_t timedRead() {
      uint32_t prev_millis = millis();
      do {
        if (peek()) return read();
      } while (millis() - prev_millis < time_out);
      return 0;               // indicates timeout
    }

Did you mean Serial1.peek()? I don't think that ever returns 0. If the buffer is empty I would expect it to return -1 (like Seria1.read() would).

I think you meant:

    uint8_t timedRead() {
      uint32_t prev_millis = millis();
      do {
        if (Serial1.available() != 0) return read();
      } while (millis() - prev_millis < time_out);
      return 0;               // indicates timeout
    }

That does basically what I wrote except the caller has to check after every call to timedRead() to see if there was a timeout (returns 0) or not.