This library implement all the required operation to drive stepper motor acting
on linear device, via a dedicated hardware (chipstet A4988 or similar).
The hardware should trigger one step on the rising edge (low to high level) of
the step pin.
In addition, two limit switches should be provided at each end of the device.
Limit switches should be connected on the normally close (NC) position,
i.e. when it is pushed, the circuit is open.
All the operations are interrupt driven in this library, so functions never
block and you don't have to provide any run() function in your main loop.
This has been done to run perfect timing when driving the motor.
Multi instance (i.e. many motors), are supported, it could be increase using
the MAX_INSTANCES macro. You don't have to decrease it, even you drive less
motor than the current value : the implementation of the class is done so that
only the memory is allocated only for the motor you are using in your code.
Take care when running many instance on low speed µC that is could drive to
continuously interrupt the main loop (no remaining time for other operations)
Timing & speed are very important for stepper operations.
Please take a look at the wiki page of the library if you have to tweak timings.
Limitations:
- PCINT : the library use pin change interrupt for limit switches.
As we don't know which pins are used, all the vectors have been redirected
to the same IRQ function. This could lead to overloaded vectors, which is
illegal for µC. If you plan to use pin change interrupt in your code or
another library, please carefully consider on which pin you place your limit
switches and redirect only the required PCINT vector (in linearStepper.cpp).
SoftSerial lib use the same way, you may have to tweak it if you want to run
both library in the same program.
- No microstepping for now. If your are driving at a fixed micro stepping rate,
there is no issues. If you need to change the micro stepping rate during the
execution, you will have to update the ratio Step per mm in your code,
the library doesn't do it for you.
- Non constant acceleration rate : the library has been written to optimize
execution timing. To avoid heavy square root calculation, acceleration
computation has been simplified, with a non constant acceleration rate.
The main goal of the acceleration is to avoid missing steps, regardless of
constant acceleration rate. Note that target position include breaking phase,
so if you plan a small shift with a long acceleration distance, the motor
will never reach its programmed speed (i.e. it will accelerate and
decelerate to reach the target position).
For more information about this library please visit us at https://github.com/akira215/linearStepper-Arduino.git
Copyright (c) Akira. All right reserved.
This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA