MC9S12NE64 Ethernet question

[Blah]

I have a module built by a third party vendor equipped with the 9S12NE64 and a Bel Stewart connector module. My design team and I have found that when we plug this module into an older Ethernet switch, everything works fine. But if we plug into a newer Ethernet switch the LINKLED doesn't light and it doesn't work.

We have been able to telnet to the module when plugged into an older switch so I don't suspect the software.

Anyone else had this issue?

Thanks,

[mjbcswitzerland]

Hi

It is very probably a problem with auto-negotiation. The NE64 PHY has a bug (see the errata to the device at the freescale web site) which doesn't allow it to always achieve auto-negotation.
If you can configure your device to use either 10 or 100M according to your network (rather than auto-negotation) it may then work correctly. [I in fact never had problems with the hubs and switches in the office but could never work with my laptop directly connected when auto-neg. was configured....]

There are two workarounds. First is through configuration as described above and the second is by modifying the software to switch between 10 and 100M until it gets a link up - this takes longer but will guarantie at least that it can eventually connect.

I don't think that there are any plans to revise the silicon to solve this bug since the NE64 is not recommended for new designs - it is however a very good and reliable device so this is rather a shame. The new ColdFire M5223X family is the new flag ship which presently has the same PHY as in the NE64, with the same bugs (the second is to do with the activity LED being being too fast that it is not really visible) but freescale has announced that the bug will be removed in the next silicon (I believe at the beginning of 2007) which will certainly make it a much better device. (when I say announced I can't say where it may be documented but this was the message given at a recent freescale seminar I attended).

By the way, you can also read some more details about the NE64 and a workaround to the PHY LED problem in the following article I wrote.
http://www.mjbc.ch/documents/uTasker/NE64/uTaskerV1.2-Tutorial.PDF
I have also written an article for the M5223X running the same project as on the NE64 which may also be of interest.
http://www.mjbc.ch/documents/uTasker/M5223X/uTaskerV1.2-Tutorial-M5223X.PDF


Regards

Mark Butcher
www.mjbc.ch

PS. We have a solution for both devices (swapping is as simple as setting a compiler switch) including an operating system with integrated TCP/IP stack and chip simulator. It is free for non-commercial work and includes also free email support. Take a look at the following posting:
http://forums.freescale.com/freescale/board/message?board.id=16BITCOMM&message.id=897
PPS. The M5223X support now includes also CAN and an external file system via SPI.

(Alban highlighted links for navigation & search engines)

Message Edited by Alban on 2006-08-16 08:42 AM

[Blah]

Mark,

That solved the problem! I fixed to 100M and everything works.

Thank you very much!
Brian