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Advanced settings for COM ports

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Jonathan Anthony

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Nov 10, 2003, 8:12:10 AM11/10/03
to
From device manager, I select communications port COM1,
select the port settings tab and click to view the
advanced settings. Instead of seeing the advanced settings
I get the message:
You must have write privileges in the registry for this
device in order to modify the device's advanced settings.

I can set and save, say, the baud rate for COM1 with no
problem.

Any suggestions?
Thanks

Doug Hoeffel (eMVP)

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Nov 10, 2003, 9:25:28 AM11/10/03
to
Jonathon:

Run regedit. Select the following keys:
HKLM\SYSTEM\CurrentControlSet\Enum\Root\*PNP0501\PnPBIOS_14\Device
Parameters
HKLM\SYSTEM\CurrentControlSet\Enum\Root\*PNP0501\PnPBIOS_15\Device
Parameters

Rt. click then Permissions. Allow full control.

HTH... Doug
"Jonathan Anthony" <jonathan...@marconiselenia.com> wrote in message
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Jonathan Anthony

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Nov 10, 2003, 1:13:12 PM11/10/03
to
Thanks for that, but there is no *PNP0501\PnPBIOS_14.
There is *PNP0501\1_0_17_0_0_0\Device Parameters only:
DosDeviceName
PollingPeriod
PortName.

There is no permissions.
Any more ideas?

>.
>

Jonathan Anthony

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Nov 10, 2003, 1:20:35 PM11/10/03
to
Thanks for that, but there is no *PNP0501\PnPBIOS_14.
There is *PNP0501\1_0_17_0_0_0\Device Parameters only:
DosDeviceName
PollingPeriod
PortName

There is no Permissions.
Any more ideas?
Thanks

>.
>

Doug Hoeffel (eMVP)

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Nov 10, 2003, 2:04:42 PM11/10/03
to
Jonathon:

I see the keys that I mentioned for both XP Pro and XP Embedded.

The one that you mention I only see in Win 2K.

HTH... Doug
"Jonathan Anthony" <jonathan...@marconiselenia.com> wrote in message

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Andy Allred [MS]

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Nov 10, 2003, 3:48:44 PM11/10/03
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I believe this has been discussed before, you should review the thread(s) in
the Google archives for this group to see if it's the same issue for the
problem and solution below:

There are 3 missing reg keys from
HKLM\system\currentcontrolset\enum\acpi\pnp0501\2
The missing keys are:
RxFIFO
TxFIFO
ForceFifoEnable

Andy
--

This posting is provided "AS IS" with no warranties, and confers no rights.
==========================================================


"Jonathan Anthony" <jonathan...@marconiselenia.com> wrote in message

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Jonathan Anthony

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Nov 13, 2003, 11:46:04 AM11/13/03
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It has been suggested that I add to the registry:
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Enum\Root\*PNP
0501\1_0_17_0_0_0\Device Parameters]
"SkipEnumerations"=dword:ffffffff
"ForceFifoEnable"=dword:00000001
"RxFIFO"=dword:0000000e
"TxFIFO"=dword:00000010

Hoever I can not add directly.
Do I have to do this in target Designer. If so under what
component.

Many thanks

>.
>

Doug Hoeffel (eMVP)

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Nov 13, 2003, 12:11:53 PM11/13/03
to
Jonathon:

I use the "Standard PC" component so I can't speak for the ACPI registry
keys that Andy [MS] addressed.

My image does not have the 1_0_17_0_0_0 registry key so I'm not sure how
this gets created. In my image, my serial ports are represented by:

HKLM\SYSTEM\CurrentControlSet\Enum\Root\*PNP0501\PnPBIOS_14

and


HKLM\SYSTEM\CurrentControlSet\Enum\Root\*PNP0501\PnPBIOS_15

When you fix the security permissions on the "Device Parameters" key, then
upon selecting the Advanced Settings button, the following items get
created:

ForceFifoEnable
RxFIFO
TxFIFO
... maybe a few others too ?

You will need to create the SkipEnumeration item yourself I think?

I create and run a reg file post-fba to do this since I have to fix the
registry key permissions first.

HTH... Doug
"Jonathan Anthony" <jonathan...@marconiselenia.com> wrote in message

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Jonathan Anthony

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Nov 14, 2003, 9:51:27 AM11/14/03
to
Andy

I have tried adding to the registry the following:


[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Enum\Root\*PNP
0501\1_0_17_0_0_0\Device Parameters]
"SkipEnumerations"=dword:ffffffff
"ForceFifoEnable"=dword:00000001
"RxFIFO"=dword:0000000e
"TxFIFO"=dword:00000010

The regedit simply will not let me do this. Does this
have to be done through embedded studio.

Many thanks

>.
>

Slobodan Brcin

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Nov 14, 2003, 10:04:16 AM11/14/03
to
You need to change permissions to Device Parameters key so you can write.
Right click on key within regedit, and use Permissions to set your access
rights. (You must be in admin account)

Regards,
Slobodan


"Jonathan Anthony" <jonathan...@marconiselenia.com> wrote in message

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Zirong Wang

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Nov 14, 2003, 10:27:30 AM11/14/03
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if you set it during the phase 8498, you will have the privilege

Jonathan Anthony

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Nov 17, 2003, 7:02:42 AM11/17/03
to
Thanks to all who have helped. In case of others who have
the same problem, the answer is:

There is no need to anthing in the registry, from

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Enum
\Root\*PNP0501

I simply changed permissions to include write so I can

write.
Right click on key within regedit, and use Permissions to

set your access rights. (You must be in admin account).
Opening up the Advanced options under port settings and
clicking OK writes the RxFIFO and TxFIFI settings under
Device Parameters.

>.
>

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