Introduction

Python host API for manipulating the acceleration controller. Implements binary communication with the microcontroller in CDC virtual com port mode. This package not only provides a Python API but also command line scripts to operate the controller.

• start/stop sampling (in streaming mode or up to specific limit of samples)
• configure/reset device (output data rate, range, scale)
• decode samples from controller
• print samples or store in tabular separated values file

See also:

• Controller Firmware
• OctoPrint plugin Octoprint Accelerometer
• Read the Docs at 3dp-accelerometer.github.io

Example

The following example illustrates how to configure and stream from the controller using CLI. First the controller configuration takes place (left shell). The controller uses it full 16g range at an output data rate of 3200ks/s where the scale is set at full resolution, meaning each LSB equals 4mg. Subsequently, the decoder is started and waiting for the controller's data stream (right shell). Finally, on the left shell, the streaming of 7 samples is triggered. The stream from the controller also contains all required metadata for data integrity so that the decoder either reports a valid and complete stream or error.

+------------------------------------------------------------------------------------------+
| $ ./controller_cli.py set --range G16 |                                                  |
| $ ./controller_cli.py get --all       |                                                  |
| version=0.1.1                         |                                                  |
| odr=ODR3200                           |                                                  |
| scale=FULL_RES_4MG_LSB                |                                                  |
| range=G16                             |                                                  |
|                                       | $ ./controller_cli.py decode -                   |
| $ ./3dpaccel.py stream --start 7      |                                                  |
|                                       | decode stream to stdout                          |
|                                       | Sampling Started maxSamples=7                    |
|                                       | #run #sample x[mg] y[mg] z[mg]                   |
|                                       | 00 00000 -0405.600 +0210.600 -1006.200           |
|                                       | 00 00001 -0405.600 +0210.600 -1029.600           |
|                                       | 00 00002 -0397.800 +0218.400 -1021.800           |
|                                       | 00 00003 -0405.600 +0210.600 -1014.000           |
|                                       | 00 00004 -0397.800 +0187.200 -1014.000           |
|                                       | 00 00005 -0390.000 +0226.200 -1021.800           |
|                                       | 00 00006 -0390.000 +0210.600 -1021.800           |
|                                       | Sampling Finished at sample 7                    |
|                                       | Device Setup: {'rate': 'ODR3200', 'range': 'G4', |
|                                       | 'scale': 'FULL_RES_4MG_LSB', 'version': '0.1.1'} |
|                                       | Sampling Stopped                                 |
|                                       | run 00: processed 7 samples in 0.010278s         |
|                                       | (3158.1 samples/s; 227383.7 baud)                |
+------------------------------------------------------------------------------------------+

Getting Started

Create Environment

sudo apt install python3-poetry
# alternatively apply script from install.python-poetry.org as 
# described in https://github.com/python-poetry/poetry#documentation
cd host-api/python
poetry shell

# minimal installation to run controller_cli.py
poetry install

# for datavis.py, record_step.py and record_step_series.py  
poetry install --all-extras

# for development (full installation)
poetry install --all-extras --with dev --with doc

# list discovered devices
controller_cli.py device --list

# retrieve device settings
controller_cli.py get --all

# list discovered devices
controller_cli.py device --list

With Initialized Environment

cd host-api/python
poetry shell
# list discovered devices
controller_cli.py device --list

For all available CLI scripts refer to Commandline Scripts.