Prolific USB to serial in Windows vista

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#1
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(Notification)
It seems that changes in these settings (bps/databits/paraty/stopbitsflowcontrol:

http://www.quatech.com/support/USB_cp_change.gif
are not passed to the communication port. Neiter are they read correctly. It is a dead thing, it does not read or wright at all.

Is this normal?

But change the COM Port Number there is processed correctly!

The only way I can do it is by using the console cmd.exe with MODE, COMn and so on.
Apparently the device manager 'Port setting' form makes no connection with Prolific ser2pl.sys driver.

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Normally the application will overide these settings.

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I do not use an application (except cmd.exe console).
Apparently plugging in is an application then...
After I plug in the USB-serial device I see these defaults from MODE COM13 (my USB-serial is at com13):

Baud: 1200
Pariteit: None
Databits: 7
Stopbits: 1
Time-out: OFF
XON/OFF: OFF
CTS-handshaking: OFF
DSR-handshaking: OFF
DSR-reactiesnelheid: OFF
DTR-circuit: ON
(other settings are OFF or HS)
RTS-circuit: ON (other settings are OFF or HS or TG}

If I change 1 of the first 4 items the other 3 will fall back to their default values, so if I want 8 databits and 2 stopbits and 9600 baud I have to change them all together 1 a single command.
The lower 7 values (ON or OFF/HS) may be changed individually from the console, as long as the USB plug is in the computer.

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Quote:

I see these defaults

"see" them where?

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I "see" them in the cmd.exe window.

BTW, by now I just found that these defaults ARE "normal".

Microsoft http://support.microsoft.com/kb/112841

They say: a proper written application should read in the registry the settings the user selected in the control panel....

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Or most serial programs (think Hyperterminal, Terterm, etc.) offer the user serial setup dialogs and just pick sensible defaults there. If the app is Posix it can just use tcgetattr() and tcsetattr().