dawiddwornicki / adapterapi

Provides python-based interface to control Step-motor-adapter-for-RPi

AdapterAPI

Brief

Bring simple python-based API for interfacing Step Motor Adapter.

This software was developed on Raspberry Pi4 as a host machine.

Tools needed

Software

• Python 3 installed on target machine.

Hardware

• Step-motor-adapter-for-RPi as a board to interface with. It must have the newest firmware flashed.

Optional

• RS232 converter to use as UART master interface if other target board is being used

Instalation

In order to download all neccesary libraries, a build_requirements.txt file has been created. In order to fetch run following command in terminal:

python3 -m pip install -r build_requirements.txt

It is also recommended to update gcc to newest version. On linux-based computers run:

sudo apt-get install gcc

Target port configuration (Raspberry Pi4)

It is necessary to configure your UART port first to be able to send frames.

Raspberry Pi4

As Adapter API is using Terminal /dev/ttyAMA0 add these two lines at the end of your config.txt file:

enable_uart=1
dtoverlay=miniuart-bt

Check official RPi documentation for details and on how to configure UART ports.

NVIDIA Jetson Nano

On NVIDIA Jetson Nano (assuming Jetpack SDK is installed) two steps are required:

1. execute following three commands:

systemctl stop nvgetty 
systemctl disable nvgetty 
udevadm trigger

2. Add your user to group dialout. Remember to logout and login for changes to take effect.

Credits:

• post on www.jetsonhacks.com
• question on askubuntu.com

Available commands

AdapterAPI class has following methods:

General methods

• CMD_GetCurrentConfig() - Prints current port config to terminal.
• CMD_CheckConnection() - Sends acknowledgement command and returns true if succedded.
• CMD_ForceStopAll() - Forces to stop every movement of steppers, servos and pump

Stepper-specific methods

• CMD_STEPPER_MoveToCoordinate(X, Y, Z) - Moves controlled cartesian coordinate system to specified position for 3 axis'. Takes 3 parameters, each meaning desired coordinate in [mm] of each axis. Parameters must be in range of -9999 to 9999.
• CMD_STEPPER_Rotate(X, Y, Z) - Rotates stepper motors by a specified number of rotations at the same time. Takes 3 parameters, each meaning desired number of rotations for each axis. Parameters must be in range of -9999 to 9999.
• CMD_STEPPER_SetCurrentPositionAsZero() - Sets current position of stepper motors to be zeroed. Useful after power-up.
• CMD_STEPPER_ForceStopMovement() - Forces to stop every movement of steppers. Returns true if succedded, False if not succeeded.

Pump-specific methods

• CMD_PUMP_RotateForMs(time) - Rotates pump for desired time in [ms]. Parameter must be in range of -9999 to 9999.
• CMD_PUMP_FeedWater(mililiters) - Turns on water pump to pump desired amount of water in [ml]. Parameter must be in range of -9999 to 9999.

Food-dispenser-specific methods

• CMD_DISPENSER_Rotate(FoodA, FoodB) - Rotates food dispensers by a set number or rotations. Parameters must be in range of -9999 to 9999.

Example usage

An example.py file has been written to demonstrate usage of all commands available in this library, it can be run as following:

python3 example.py