Copyright © 2015 Robot Circuits, LLC
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RCAT-1A Rev A3 Designer’s manual
Serious Power for the Serious Designer
Demonstration Software
Another point of aggravation that you have probably encountered at some time or another if you have been doing this
very long, is trying to gather up all the function libraries, configuring development environments, loading demonstration
code, downloading datasheets for various devices, and more, only to find that the library(s) you thought you wanted
were either out of date, or no longer available, or just plain broken, and the IDE configuration was cryptic and not
documented well enough to let you easily load the demo software, and the demo software was SO basic that it was, for
all intents and purposes, useless.
To that end we have provided a fully functional software solution that, once you have installed the Atmel Studio, and
have copied the solution files to the proper locations on your computer, can be simply loaded and executed without all
the usual drama.
We have provided the solution as a real-time operating system that uses a special AVR port of the open-source
FreeRTOS library (see the
FreeRTOS page here
). Please note that the RCAT™ Startup solution uses files from the
published release of FreeRTOS that have been adapted to run with the RCAT™ board. These files have been annotated
as such and renamed with an “RCAT_” prefix to identify them.
Yes – you SHOULD read the FreeRTOS documents and learn how to use the O/S. But the solution will load, compile and
run even if you don’t at first.
The solution provided is more than just a “Demo”. It can actually serve as a root project for your applications. In it we
have written examples for:
Operating the onboard LED
Configuring and reading the accelerometer chip (pitch and roll in degrees)
Accessing Extended RAM (the system comes configured to use Extended RAM as the heap and implements the
heap management routines of FreeRTOS, allowing dynamic memory management.
Reading and writing the 1M-bit Serial EEPROM
Reading and writing the Ethernet com (assumes a Netburner™ is attached)
Operating the onboard mosfets
Configuring a simple PWM-based servo control
Configuring one ADC channel and reading a voltage on it
Performing timer-based read of a sonar distance measurement device similar to the Parallax PING™
These modules are all written as separate tasks in the FreeRTOS multitasking system that can be installed, removed, or
reprioritized as you desire. Figuring out how to extend these tasks and how to extend the demonstrated techniques (for
example to operate other USARTs) is a simple jump from this point.
As time progresses, we will extend this solution to provide modules for interfacing to other popular devices. We also
welcome the addition of support for various modules on the github project.
