Getting Started

Installation

1. Download and unpack the zip file of the latest release.
2. Attach an Espressif ESP32 microcontroller via serial to your computer.
3. Run sudo ./espresso.py flash to install Lizard on the ESP32. Add --device /dev/<serial device name> to pick the adapter yourself, for example when several are attached.

Try Out

You can launch an interactive shell with ./monitor.py to try out configurations and watch Lizard outputs (see tools for more details). To verify that the communication is working, use one of the following commands to generate some output:

core.info()
core.millis
core.print("Hello, Lizard!")

See the module reference for other commands.

To try out individual modules, you can get their current properties or unmute them for continuous output, e.g.:

estop = Input(34)
estop.level
estop.unmute()

Wiring

Of course you should connect the ESP32 to some hardware you want to control. From basic pins like LEDs (see Output) and buttons (see Input) to communication via CAN and control of stepper motors.

Startup Script

You can create a startup script for rules which should be directly applied after boot of the microcontroller. Simply write the commands into a file like on_startup.lizard and set them with

./configure.py on_startup.lizard

Add the device path (e.g. ./configure.py on_startup.lizard /dev/<serial device name>) to pick the adapter yourself, for example when several are attached.

See Tools for more details.

If loading the startup script fails, for example because a module cannot be created, the microcontroller prints the error and restarts to try again. After two failed attempts it boots without the startup script, prints error: startup skipped after 2 failed boots (...) with the last reason and stays reachable over the command-line interface, so the script can be fixed with !-, !+ and !.. A crash or watchdog reset during the first seconds after boot counts as a failed attempt as well. A power cycle or a reset over the EN pin clears the counter.