Experimental Physics and
Industrial Control System

Eric Norum <[email protected]> · Fri, 16 Nov 2007 07:23:16 -0600

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 <[email protected]>
Advanced Photon Source
Argonne National Laboratory
(630) 252-4793

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System