From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Fri, 11 May 2007 14:46:07 +0300
From: Maksym Veremeyenko <verem@domain.hid>
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Subject: Re: [Xenomai-core] 16550A driver and Moxa card / solved
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To: Jan Kiszka <jan.kiszka@domain.hid>
Cc: "xenomai@xenomai.org" <xenomai@xenomai.org>

Jan Kiszka =D0=C9=DB=C5=D4:
>> moxa: 912.600/115.200 =3D 8
>> xeno: =3D 7
>=20
> Yeah, hard arguments. This really cries for a moxa tweak. (The
> alternative would be to pass an artificially increased baud_base - but
> that would be _really_ ugly and we could also ask the user for the
> divider directly...)

As i correctly understand mxser use formula:
       +-
       | base/baud, baud <> 134
div =3D |
       | 2*base/(2*base + 1), baud =3D=3D 134
       +-

Jan's driver use:

div =3D (base + baud/2)/baud

What is actual

div =3D base/baud + 0.5

That seems more correct for rounding....


In additional:
1. You should use 921600 value instead of 912.600.
2. Interface is asynchronous and (IMHO) data could be transfered in a=20
range of frequencies (BAUD +/- RANGE%)



--=20
________________________________________
Maksym Veremeyenko