Experimental Physics and
Industrial Control System

Eric Norum <[email protected]> · Tue, 15 Feb 2011 19:29:23 -0800

On Feb 15, 2011, at 4:59 PM, John Dobbins wrote:

> On 2/15/2011 4:13 PM, Eric Norum wrote:
>> The problem is that the network stack provided by the uCDIMM bootstrap has a *very* small receive queue.    If you have any significant broadcast traffic on the network segment you'll start losing TFTP packets resulting in massive slowdowns.
>> 
>> Possible workarounds:
>> 1) Burn your first application into the ColdFire using TFTP on a quiet network segment -- I did this by connecting the ColdFire directly to my laptop -- with only two device on the network the TFTP transfers run very fast.
> 
> That is just what I did to get around this.
> 
> 
>> 2) From then on use the EPICS flash memory driver to update your application.  The RTEMS network stack is much more robust and doesn't drop packets so easily.
> 
> I don't know about this EPICS flash memory driver. Is there something I should have read?

You can get this support from
	http://www.aps.anl.gov/epics/modules/instrument/mcf5282/index.html

>From the Description section of this support module:
The mcf5282 module contains drivers for the RTEMS-uC5282 target (ColdFire MCF5282 uCDIMM) including the queued analog to digital converter, the I2C interface, the bootstrap flash memory, I/O ports GPTA/B, and the CPU load. It also provides support for flash memory connected through an external FPGA, and FPGA configuration flash memory.

-- 
Eric Norum
[email protected]

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System