Re: EPICS on RTEMS

[Eric Norum <norume@aps.anl.gov>]

We have a number of ColdFire uCDIMM modules with 16 MB of RAM and 4.5  
MB of flash.
http://www.arcturusnetworks.com/products/uc5282/
In one of the larger applications (beam position monitor) this  
handles about 500 PVs.

I think that 16 MB of RAM is probably as low as you'd want to go.  I  
used to run some Motorola 68360 systems with 4 MB of RAM, but that  
was really limiting.

It depends somewhat on the CPU architecture, but typically an  
application+EPICS+RTEMS is one to two MB of code space.  Here's what  
the aforementioned BPM IOC uses:
m68k-rtems4.7.1-size srmonopulsebpm/bin/RTEMS-uC5282/srbpm
   text    data     bss     dec     hex filename
1629008   60032  105520 1794560  1b6200 srmonopulsebpm/bin/RTEMS- 
uC5282/srbpm

Flash -- you need only enough to do a net boot.  1M would be plenty.


On Nov 16, 2007, at 4:37 AM, Heinrich du Toit wrote:

> Hi
>
> Can somebody give me an indication of how much flash/SRAM is needed  
> by a system on RTEMS to run EPICS?
>
> thanks
> -Heinrich

--
Eric Norum <norume@aps.anl.gov>
Advanced Photon Source
Argonne National Laboratory
(630) 252-4793