On Thu, 27 Jun 2013 at 20:53, Frank Schäfer wrote:
Am 27.06.2013 19:14, schrieb Reinhard Max:
But the same datasheets also contain the statement I cited before,
that the baud rate generator can be programmed to *any* baud rate
between 75 and the limit of the respective chip.
Well, all I can say is that the latter doesn't apply to my device.
When has this datasheet been released ?
April 2004 (Page 6, 2nd paragraph):
http://www.ak-modul-bus.de/cat/documentation/ds_pl2303x_v11.pdf
Also on page 10 of the 2006 release of the same document:
http://prolificusa.com/pdf/PL-2303XA.pdf
I also fixed the driver to report the baud rate it actually uses. ;)
Applications can check the resulting baud rate and decide if it is
sufficient for their purpose.
... which makes them dependent on this particular driver?
Or are other drivers doing the same?
Throwing an error if the device can not be set exactly to the
requested baud rate isn't a good idea, because
a) even good hardware usually doesn't allow real continuous baud
rate adjustment
b) communication works fine as long as the baud rate deviance is
within an acceptable limit (which differs between applications)
Those points apply to the small roundings that are needed to get to
the next rate that is technically possible, but I don't think they are
valid for roundings to the next value in the default list, which might
be too far off to get a usable connection.
Does your device use a generic (Prolific) USB ID ?
Yes.
But I am interested in improving this driver generally, not only to
get it working on my particular device, which BTW is a data cable for
Siemens mobile phones as it is often used by hobbyists to communicate
with embedded hardware.
cu
Reinhard
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