Date of Notification:      05/12/2014

 

Products affected:          Certain MTCDP products with 6ns SDRAM installed

 

Issue Reported:                Intermittent lockups of OS in the field.

 

Symptoms:

Heartbeat LED stops flashing.

Unit is unresponsive.

Debug port is unresponsive.

Power cycle clears.

 

Serial number range affected:

16711849 – 17627298

 

Serial numbers NOT affected within the above range:

 17524134

17537320 – 17537324

17540271

17591323 – 17591326

17591329 – 17591330

17591458

17601958 – 17601994

17602242

17604628 – 17604632

17614141 – 17614169

 

Starting serial numbers already updated:

17627299 and greater or units with a DOM of 5/2/2014 or later

 

Details:    

 One customer reported intermittent lockups of deployed MTCDP

Not all of the customer’s deployed MTCDP units were showing an issue.

The time to lockup varied from a few hours to a few weeks.

 

Analysis:  

A few of the units that were showing an intermittent lockup were retrieved from the customer.    There was an intermittent interaction between the SDRAM and the default slow slew rate setting of the MTCDP that would cause access errors on some units.

The SDRAM is a newer 6ns part that was qualified as an approved replacement part for an EOL 7.5ns part.  At the time of the approval of the 6ns SDRAM in Q3/2013, there was no indication of issues with the MTCDP using this replacement SDRAM.

The MTCDP has been shipping with a slow slew rate setting since the release of CoreCDP 2.0.1 in 2011.   The previous 7.5 ns SDRAM has never shown to have an issue with the slow slew rate setting.

 

MTS Action:       Product put on hold and new  boot code created to correct issue.

We changed the setting in the boot code of the processor to set the SDRAM controller slew rate to FAST instead of SLOW, which corrects the issue of intermittent lockups of units previously showing this issue.  Changing the boot code does not affect the Core CDP main code already programmed into a unit.

Products are being updated at the factory and shipments have resumed

 

Customer Action:

It is recommended that customers download the update from the web and update their boot code if they experience an issue or as a precaution to avoid possible future issues.

Instructions on how to update the boot code:

1. Download the file: http://www.multitech.net/corecdp/images/2.2.2/mtcdp/at91bootstrap-mtcdp-2.13-r1.corecdp6-fast-slew-rate.bin

2. To flash the new boot code,  please do the following:

a. Copy the fast slew rate bin file into your TFTP server folder

b. rename the file to “oe_bootstrap.bin“.

c. Restart your CDP and go into the U-boot prompt.

d. Enter the command: printenv        [This will list out the current U-boot environment.]

 Look for the variables:

-bootstrap_file=oe_bootstrap.bin       [make sure it exists]

– ipaddr=xxx.xxx.xxx.xxx      [This to your CDP ipaddress]

– serverip=xxx.xxx.xxx.xxx   [Modify to your TFTP server ipaddress]

Notes: Type help for information on how to set/unset the variables.

d. Then type: run tftp_bootstrap

e. Once done, type: reset

f. You should see the message: FAST slew rate

 

If you have questions or cannot update your product yourself, please contact product support for additional assistance.

At our web portal:  https://support.multitech.com

Or email:  tsupport@multitech.com