[ECOS] non-standard serial baud rates

[ECOS] non-standard serial baud rates

[Trenton D. Adams]

Since I'm doing those SSI drivers for the EDB7XXX, I'm wondering.  Is
specifing a non-standard baud rate going to make the API croke?  What I
really want to know, are the baud rates used by anything other than MY
(tm) serial driver?

I ask because the eCos reference manual says "The field \"baud\"
contains a baud rate selection.  This must be one of the values:" and it
proceeds to display the CYGNUM_SERIAL_BAUD_XXXXXX macros.



Trenton D. Adams
Extreme Engineering
#17, 6025 - 12 St. SE
Calgary, Alberta, Canada
T2H 2K1

Phone: 403 640 9494 ext-208
Fax: 403 640 9599

http://www.extremeeng.com

Re: [ECOS] non-standard serial baud rates

[Jonathan Larmour]

"Trenton D. Adams" wrote:
> 
> Since I'm doing those SSI drivers for the EDB7XXX, I'm wondering.  Is
> specifing a non-standard baud rate going to make the API croke?  What I
> really want to know, are the baud rates used by anything other than MY
> (tm) serial driver?
> 
> I ask because the eCos reference manual says "The field \"baud\"
> contains a baud rate selection.  This must be one of the values:" and it
> proceeds to display the CYGNUM_SERIAL_BAUD_XXXXXX macros.

The baud rates are defined in io/serial/current/include/serialio.h. That's
the extent of the public API. You couldn't use a publically defined baud
rate. But there's nothing to stop you adding more (although I would start
it at an integer well after that corresponding to
CYGNUM_SERIAL_BAUD_230400), e.g. 100.

But what figures are we talking about? Perhaps it would be better for us
just to add them in the main sources?

Jifl
-- 
Red Hat, Rustat House, Clifton Road, Cambridge, UK. Tel: +44 (1223) 271062
Maybe this world is another planet's Hell -Aldous Huxley || Opinions==mine

RE: [ECOS] non-standard serial baud rates

[Trenton D. Adams]

It's about time I setup my SMTP server at home.  I hate not being able
to reply to Discussion messages from home.

Anyhow, the baud rates are
4 kbps,
16 kbps,
64 kbps,
128 kbps

I don't know if these are standard for SSI interfaces or not.  Are they?

-----Original Message-----
From: ecos-discuss-owner@sources.redhat.com
[ mailto:ecos-discuss-owner@sources.redhat.com ] On Behalf Of Jonathan
Larmour
Sent: September 12, 2001 5:53 PM
To: Trenton D. Adams
Cc: eCos Discussion
Subject: Re: [ECOS] non-standard serial baud rates


"Trenton D. Adams" wrote:
> 
> Since I'm doing those SSI drivers for the EDB7XXX, I'm wondering.  Is 
> specifing a non-standard baud rate going to make the API croke?  What 
> I really want to know, are the baud rates used by anything other than 
> MY
> (tm) serial driver?
> 
> I ask because the eCos reference manual says "The field \"baud\" 
> contains a baud rate selection.  This must be one of the values:" and 
> it proceeds to display the CYGNUM_SERIAL_BAUD_XXXXXX macros.

The baud rates are defined in io/serial/current/include/serialio.h.
That's the extent of the public API. You couldn't use a publically
defined baud rate. But there's nothing to stop you adding more (although
I would start it at an integer well after that corresponding to
CYGNUM_SERIAL_BAUD_230400), e.g. 100.

But what figures are we talking about? Perhaps it would be better for us
just to add them in the main sources?

Jifl
-- 
Red Hat, Rustat House, Clifton Road, Cambridge, UK. Tel: +44 (1223)
271062 Maybe this world is another planet's Hell -Aldous Huxley ||
Opinions==mine

Re: [ECOS] non-standard serial baud rates

[Grant Edwards]

On Wed, Sep 12, 2001 at 05:18:06PM -0600, Trenton D. Adams wrote:

> Since I'm doing those SSI drivers for the EDB7XXX, I'm
> wondering.  Is specifing a non-standard baud rate going to make
> the API croke?

I wrote my driver to accept one of the enumeration values or a
plain baud rate (e.g. the integer value 19200). IMO, using
enumerated values for baud rates is an obsolete concept left
over from the days when an "int" wouldn't hold all legal baud
rate rates.

> What I really want to know, are the baud rates used by anything
> other than MY (tm) serial driver?

Not as far as I can tell.

> I ask because the eCos reference manual says "The field
> \"baud\" contains a baud rate selection.  This must be one of
> the values:" and it proceeds to display the
> CYGNUM_SERIAL_BAUD_XXXXXX macros.

My driver accepts any integer value. If the value is leass than
150, it is interpreted as an enumerated constant, if it's >=150,
then it is interpreted as a buad rate and I set the divistor
accordingly.  The resulting clock values values for some
arbitrary baud rates are not exact, but I don't see any reason
to stick with the enumeration scheme.

-- 
Grant Edwards
grante@visi.com