ETA/OS is a small scale, embedded kernel and/or operating system. It provides basic hardware abstraction allowing an application programmer to build somewhat portable embedded applications. Some of its features:

• Memory management
• Scheduler (semi-SMP ready)
• Interrupt management
• Timer management
• Driver core
• Several device and sensor drivers

ETA/OS is licenced as GNU Lesser General Public Licence version 3 or newer. The COPYING file should contian more information about the licence, or if it's not included, look at http://www.gnu.org/licences/.

ETA/OS
Copyright (C) 2014, 2015, 2016, 2017  ETA/OS developers <[email protected]>

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser Lesser General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program 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 Lesser General Public License for more details.

You should have received a copy of the GNU Lesser Lesser General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.

In order to build ETA/OS you need a working cross compile toolchain and a host toolchain to build the DevOps applications. The entire setup process is described here. The build scripts has a builtin help function. Run make help ARCH=<arch> to see all available targets.

ETA/OS comes with a set of unit tests, which can be found in the usr/tests directory. These tests can be ran manually, ofcourse, or the running process can be automated for most tests using a tool called Calypso. Calypso can be download as a Ruby gem:

user@pc# gem install calypso

Running all available unit tests can be done with the following command:

user@pc$ calypso -yfc usr/calypso.yaml

For test configurations, please check the Calypso help: calypso -h command.

To see how you can help improving ETA/OS, read the contribution guide. You can find it in the CONTRIBUTING.md file in the repository or on the web.

• Solving the avrdude timeout for the Arduino Mega / ATmega2560:

For some reason, avrdude is sometimes unable to properly communicate with the ATmega2560. This solution can be tried when you receive the following error:

avrdude: stk500v2_ReceiveMessage(): timeout

If you run into this error, there are 3 'scripts' provided to work around it:

user@pc$ scripts/avrdude_timeout_fix [DEVICE_FILE]

Now you can upload your binaries to the ATmega.

If you would like a tty-fix script and an upload in one, then you should give either calypso (for unit tests) or scripts/avr_upload a try.

user@pc$ scripts/avr_upload -h

Please note that these are not 'run once and be good forever' scripts. They need to be ran before every upload.