[ANNOUNCE] Real-Time USB stack for RTAI

Jan Kiszka kiszka at rts.uni-hannover.de
Fri Apr 22 16:01:00 CEST 2005

Hi all,

as another sign for the good progress the RTAI community is making at 
the moment, I'm proud to announce another new project: RT-USB. It 
emerged from the diploma thesis of one of our students, Joerg Langenberg 
(he did even more than this stack).

RT-USB is a hard-real-time USB stack based on RTAI. It aims to attach 
the increasing number of real-time-relevant USB devices like digital I/O 
interfaces, DACs, RS232 converters, all kinds of cameras, etc. to the 
RTAI domain.

  - USB stack core with bulk and control message support
  - UHCI host controller driver (i.e. USB 1.1)
  - Demonstration kernel-mode program that exchanges some packets with
    arbitrary USB devices ("USB-ping")

  - UHCI-compatible host controller
  - Linux Kernel 2.6
  - RTAI/fusion 0.7.2 or later

Instead of converting a full featured stack with real-time problematic 
design elements like the one of Linux (dynamic resource management), 
Joerg went the "hard" way and wrote one from scratch, of course inspired 
by implementations in Etherboot and Linux. Therefore, this version has a 
few limitations yet. However, it is already usable for a lot of 
peripheral devices, you just have to write/port the high-layer drivers. 
There is a simple "USB-ping" example in the source tree.

Future Plans
  - EHCI host controller (USB 2.0)
  - RTDM-based (as known from RTnet) core API
  - Port to RTAI 3.x series
  - integration of relevant high-layer drivers (Joerg wrote "just" a very
    specific camera driver)
  - Tuning USB to its limits and further explore its real-time

We've rolled out this project early, as there is already another 
developer waiting to join in order to implement the EHCI driver. 
Actually, I created the project and wrote this announcement on behalf of 
Joerg, because he is very busy right now with writing his thesis. But he 
will likely continue his work on RT-USB full-time at our institute for a 
few months after graduating - as long as he doesn't get an industry job 
more quickly...

Oh, I almost for forgot to give you the most important information, the 
project homepage:



PS: Sorry, we had no time to convert German code documentation to 
English yet.

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