MicroMonitor TFS & RTEMS

[Steve Holle]

We are booting into micromonitor and running RTEMS with our app.  We are 
using the micromonitor TFS instead of incorporating a flash file system 
into RTEMS.  We then use micromonitor calls to handle all flash access.

At 10:28 AM 9/28/2004, Ed Sutter wrote:
> > >All,
> > >Last night I took Joel's advice (from a while ago) and used the
> > >tftpDriver.c code as a model for integrating TFS into RTEMS as
> > >a mountable FS.  I shamelessly reused a good portion of the
> > >generic parts of the code in tftpDriver.c (in places simply
> > >changing _tftp_ to _tfs_).  At first glance, it appears to be
> > >working fine, and now I can access TFS files through RTEMS's FS.
> > >
> > >So, assuming there must be more to it (it just can't be that easy!),
> > >what kind of limitations are imposed by this interface?  I see
> > >there is a limited number of interfaces (no ioctl, fstat,
> > >etc...), but I hope to eventually get that stuff working.
> > >Are there any other "gotchas" I need to be aware of for
> > >integrating TFS into RTEMS as a mountable FS?
> > >
> > I don't know TFS -
>
>Quick description:
>TFS (Tiny File System) is a major component in a boot monitor that I wrote
>called MicroMonitor.  As a part of the monitor, it provides a very 
>maintainable
>(IMHO) platform for an embedded system.  TFS, to be honest, isn't really a
>file system, rather it provides a power-safe means to organize on-board
>flash into name space, but still allows the user to access the data at the
>raw memory level.  The TFS API gives the appearance of an FS (read,
>write, open, close, ctrl, stat, seek, etc...) but under the hood it's just
>a glorified linked list, with code that deals with flash defragmentation
>in a powersafe way.
>
> > It's desirable to support directory lookup and fstat.
> > Without directories, 'pwd' won't work.
> > Existing software often also uses seek.
>
>Ok, that sounds reasonable.  TFS doesn't have a directory heirarchy;
>however, I think (?) it will be easy to fake this.  The fstat and seek
>functionality is already in TFS's API, so that should easily hook into
>RTEMS.
>
>Thanks!
>Ed

Steve Holle
Link Communications, Inc.
1035 Cerise Rd.
Billings, MT  59101
sholle at link-comm.com