Serial Port problem with 823e on Embedded Planet

Wolfgang Denk wd at
Thu Jun 28 04:09:55 EST 2001

Dear Michael,

in message <E1836A7F3557D311A14000805F9F36FCD4E383 at> you wrote:
> I have an Embedded Planet with a LITE_DW Motorola 823 PPC using a HIOX
> interface board. I am trying to debug a program sending out data from
> ttyS1 and reading it back in on ttyS2. The latest patch has been applied

I guess you are using the SMC ports for the ttyS* ?

> I want to be able to send any char over the serial link, so I've resorted to
> using "raw" mode. The problem is that if an overrun occurs on the receive
> side, there is nothing I can sense to indicate this situation. Has anyone
> run into this problem and/or is there a solution to my dilemma?

In raw mode you're kind of lost - the SMC's don't have any  handshake

You could switch to use SCC's instead. We have a modified driver that
supports full HW handshake on all SCC's (and you  can  configure  the
number and size of I/O buffers to optimize for throughput).

Wolfgang Denk

Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd at
A direct quote from the Boss: "We passed over a lot of good people to
get the ones we hired."

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