NodeMCU Serial Issues

Hardware
1

I’m trying to get a NodeMCU working so I can replicate Bruh’s LED strip setup.

I’m getting stuck very early on- I can upload a sketch to the NodeMCU, but I can’t read anything from the serial port, just gibberish. The first few lines (that I gather are written before the sketch is run) are fine, but once it gets into the sketch I just get gobley-gook.

Here’s the sketch:

void setup() {
  Serial.begin(115200);

}

// the loop routine runs over and over again forever:
void loop() {
  Serial.print("Hi");
  delay(1000);      
}

Here’s some serial output from that sketch:

     ets Jan  8 2013,rst cause:2, boot mode:(3,6)

load 0x4010f000, len 1384, room 16 
tail 8
chksum 0x2d
csum 0x2d
v4ceabea9
~ld
T⸮T⸮T⸮T⸮T⸮T⸮T⸮T⸮T⸮T⸮T⸮T⸮T⸮T⸮T⸮T⸮T⸮T⸮T⸮T⸮

The “T⸮” is printed about every second, as expected with the delay in the sketch.

I’m pretty confident that the sketch is being uploaded, because I was able to load the blink sketch, and change the rate of the blinking for the on-board LED. (Although the behavior was opposite was I expected, low was high and high was low.)

I’ve tried changing the baud rate in the sketch and in the serial monitor, and in the COM port settings, and tried very slow rates (9600) to no avail. Can anyone help me?

2

Per other reviews on Amazon, there’s some bug with some boards from this vendor where you have to use a specific baud rate in the sketch, and actually use a different baud rate for the monitor. Doing that I was able to get the monitor to work. But, for these buggy boards the wifi doesn’t work either, so I’m returning it and getting a replacement.

3

Which boards does this apply to (link?)?

I just ordered some boards and I hope I didn’t get the wrong ones. :worried:

4

I ordered from this link https://www.amazon.com/dp/B010O1G1ES/ref=cm_sw_r_cp_apa_jRazAb4G7ZB9A
Even if you used the same one I wouldn’t worry too much. It seems more like a quality control issue than a every-board issue based on the reviews. It has good reviews and is available from prime, and I didn’t have to flash the firmware to use the arduino IDE. One reviewer mentioned that they actually got one good one and one bad one, so I actually started the return and just ordered another one.

5

Nope, not the same one’s anyway.

I ordered the one’s from MakerFocus. However, those were the other ones I was looking at buying.

I’m glad Amazon makes returns (generally) painless. Just better to not have to deal with it in the first place.

Thanks for the info.

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