[ECOS] Confusion on serial port usage

Gary Thomas gary@mlbassoc.com
Mon Aug 6 19:47:00 GMT 2007

Mike Sweeney wrote:
> I have an ARM based port that I am working with and am using the
> Generic 16X5X serial drivers. I am a little confused on diag_printf,
> HAL_DIAG_WRITE_CHAR, and how the serial device driver routines all
> play together. My board only has 1 serial port so everything has to
> share 1 output. My question is, if I include the serial port drivers
> (Generic 16X5X), should diag_printf() be using HAL_DIAG_WRITE_CHAR()
> or should it be transmitting characters via the serial port driver?

The diagnostic routines (e.g. diag_printf()) always use HAL_DIAG_WRITE_CHAR
Your interrupt driven serial driver should play nice with this - we've
taken care to make it work properly on "supported" platforms.

> In my configuration diag_printf() is transmitting characters via
> HAL_DIAG_WRITE_CHAR() through the virtual vector table. I have my
> configuration set so that eCos claims the virtual vector table and
> there are no monitor services used. Can someone help me straighten
> this out?

This shouldn't be necessary if you have a working RedBoot.

As mentioned, this should "just work".  If it doesn't, maybe
we can help if you describe the failures/difficulties in detail.

Gary Thomas                 |  Consulting for the
MLB Associates              |    Embedded world

Before posting, please read the FAQ: http://ecos.sourceware.org/fom/ecos
and search the list archive: http://ecos.sourceware.org/ml/ecos-discuss

More information about the Ecos-discuss mailing list