Troubleshooting TJBot

Having difficulties making a TJBot recipe work? Please see these frequently asked questions.

Testing your TJBot's hardware

As TJBot has a number of hardware components that may or may not be hooked up correctly, we provide an additional set of hardware tests. These tests are contained in the tests directory and may be run via npm run-script. See the instructions for running the hardware tests for more detail.

How to debug TJBot

TJBot uses the winston library to log information about its internal operation. You can adjust the log level through the log.level configuration parameter as follows:

const tj = new TJBot({
    log: {
        level: 'verbose'
    }
});

winston defines an number of logging levels, but in general the ones used by TJBot are info (lowest detail), verbose (more detail), and silly (highest level of detail).

If you have an issue with TJBot, try increasing the log level first to see more detail as to what could be going on.

LED Issues

LED doesn't light up

If the LED does not light up, you can try moving the power from 3.3 to 5 volts. If neither the 3.3v or 5v pins work, you will need a 1N4001 diode. The diode is inserted between the power pin of the LED (the shorter of the two middle pins) and the 5v pin on the Raspberry Pi.

LED shows the wrong color

By default, TJBot sends colors to the LED in "RGB" format. Some LEDs may expect colors to be sent in the "GRB" format. The configuration option shine.grbFormat lets you switch between these two formats.

const tj = new TJBot({
    shine: {
        grbFormat: true
    }
});

LED still shows the wrong color, rapidly flashes different colors, or flashes when audio is playing

If the LED shows the wrong color, rapidly flashes different colors, or flashes when audio is playing, it may be due to interference with the built-in audio hardware. Depending on your configuration of Raspbian, the sound drivers may be more aggressive in taking away control of GPIO 18 from other processes. If your LED shows random colors instead of the expected color, use this trick to fix it.

$ sudo cp bootstrap/tjbot-blacklist-snd.conf /etc/modprobe.d/
$ sudo update-initramfs -u
$ sudo reboot

After TJBot finishes rebooting, confirm no "snd" modules are running.

$ lsmod

LED doesn't work on Raspberry Pi 4

There is a known issue in the rpi-ws281x-native library on Raspberry Pi 4 that prevents the LED from shining and you may see the following error:

error initializing - 3 Hardware revision is not supported Verbose: shining my LED to RGB color 0xFF0000 Segmentation Fault

There is a software workaround which involves checking out code from a special branch. As of this writing, this branch has not been merged into the main rpi-ws281x-native library. Within the tjbot/recipes/speech_to_text directory, run the following commands:

$ npm install rpi-ws281x-native@latest
$ git clone --single-branch --branch raspi4support https://github.com/jimbotel/rpi_ws281x.git
$ cp -r rpi_ws281x/* node_modules/rpi-ws281x-native/src/rpi_ws281x
$ npm build node_modules/rpi-ws281x-native

If that solution doesn't work you can also try:

$ git clone https://github.com/jgarff/rpi_ws281x.git
$ rm -rf /var/app/node_modules/rpi-ws281x-native/src/rpi_ws281x
$ cp -r rpi_ws281x /var/app/node_modules/rpi-ws281x-native/src
$ cd /var/app/node_modules/rpi-ws281x-native
$ sudo node-gyp rebuild

I'm still having troubles with the LED!

If you have additional difficulties not covered in this guide, please refer to Adafruit's NeoPixel on Raspbeery Pi guide to troubleshoot.

Speaker issues

My Bluetooth speaker doesn't play audio

Many people have reported numerous issues regarding Bluetooth speakers and TJBot. We do not recomend using a Bluetooth speaker with TJBot, as we have never reliably been able to make it work. In some instances, audio works over Bluetooth but when TJBot speaks, the speech is clipped (e.g. the first word is dropped) or garbled. In other instances, audio fails to work at all over Bluetooth, even when it works outside of TJBot (e.g. with ALSA's aplay command). Therefore, we recommend using a USB audio adapter and connecting a speaker to its 3.5mm audio jack.

Servo issues

TJBot's arm is waving backwards or upside-down

Different models of servo may use different "stop points" to set the position of the servo. The TJBot library uses a set of stop points that work with the RioRand SG90 9G servo. If these stop points don't work for your servo, try experimentally redefining the stop points defined in TJBot.SERVO:

TJBot.SERVO.ARM_BACK = <your stop point> // default: 500
TJBot.SERVO.ARM_UP = <your stop point> // default: 1400
TJBot.SERVO.ARM_DOWN = <your stop point> // default: 2300