Enable the 'c' states in Aptio Bios but serial port were not worked for high baud rate in win 10

Hi all,
When I enable the c states in BIOS in aptio for window 10.

I have used standard PCI com port device of pnp0500 device ID where it took
the standard serial.sys .inbox driver

I’m getting the "receive buffer overrun " it’s not worked for hight
baudrate.

When I disable the c states in BIOS side it were worked for high baudrate.

I can change the receive buffer in device manager.

What is the issue behind this one.

Is there any updates need in driver side ?

Used version 1607 win 10.

Regards,
Prabhakr v

One thing I should add is that manually setting the FIFO buffer values in
device manager to 1 byte RX / 1 byte TX resolved the issue in 29 out of 30
test attempts with the in box Microsoft driver

Using the in-box MS driver I set the buffer sizes to 4 RX / 1 TX, and it
seemed to work on our driver, it failed the first time on the MS in-box
driver. The buffer values were set in device manager, not the driver.

But getting com port detected the receive buffer overrun.

Is anyone have faced this error…

Could you please help in this issue.

I have used win 10 sample driver n samething .

Could you please anyone suggest me wat need to update to resolve t buffer
overrun.

Regards,
Prabhakr v
On 10 Jul 2017 23:43, “Prabhakar V” wrote:

> Hi all,
> When I enable the c states in BIOS in aptio for window 10.
>
> I have used standard PCI com port device of pnp0500 device ID where it
> took the standard serial.sys .inbox driver
>
> I’m getting the "receive buffer overrun " it’s not worked for hight
> baudrate.
>
> When I disable the c states in BIOS side it were worked for high baudrate.
>
> I can change the receive buffer in device manager.
>
> What is the issue behind this one.
>
> Is there any updates need in driver side ?
>
> Used version 1607 win 10.
>
> Regards,
> Prabhakr v
>

Well, let me guess (that all I’m doing): You enable C-States, the core runs more slowly, the serial port buffers don’t get serviced as quickly, and you get FIFO overflows on the serial port at high baud rate.

That doesn’t sound unusual, or unreasonable, to me.

Peter
OSR
@OSRDrivers

“Doctor, it hurts when I do this (demonstrating with his arm).”
“Well, don’t do that anymore with your arm and you’ll be fine.”

I think his complaint is reasonable, however, though I have no idea
how to solve it. I would expect the OS (or hardware) to scale up the
processor frequency to be able to service the interrupt more quickly.

Using DMA may solve the issue.

One of my other vendor SIO fix this error ( Its a COMPORT device it also
have 4 COMPort which they have their driver to fix the buffer overrun )

We are using different SIO device which has 4 comport which takes the
defaulut inbox driver and faced the buffer overrun.

To fix this error :

I will take the sample driver from win ddk 10 i.e
serenum which is compatible for PNP0500.

What scenario i have to care to fix this buffer overrun.

As you people are expert in this ,could you please help on this.

Regards,
Prabhakar V

On Tue, Jul 11, 2017 at 1:48 AM, R0b0t1 <
xxxxx@lists.osr.com> wrote:

> I think his complaint is reasonable, however, though I have no idea
> how to solve it. I would expect the OS (or hardware) to scale up the
> processor frequency to be able to service the interrupt more quickly.
>
> Using DMA may solve the issue.
>
> —
> NTDEV is sponsored by OSR
>
> Visit the list online at: http:> showlists.cfm?list=ntdev>
>
> MONTHLY seminars on crash dump analysis, WDF, Windows internals and
> software drivers!
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> To unsubscribe, visit the List Server section of OSR Online at <
> http://www.osronline.com/page.cfm?name=ListServer&gt;
></http:></http:>

Hi ,

Could you please help on this issue.

Regards,
Prabhakar V

On Tue, Jul 11, 2017 at 11:53 AM, Prabhakar V wrote:

> One of my other vendor SIO fix this error ( Its a COMPORT device it also
> have 4 COMPort which they have their driver to fix the buffer overrun )
>
> We are using different SIO device which has 4 comport which takes the
> defaulut inbox driver and faced the buffer overrun.
>
> To fix this error :
>
> I will take the sample driver from win ddk 10 i.e
> serenum which is compatible for PNP0500.
>
> What scenario i have to care to fix this buffer overrun.
>
> As you people are expert in this ,could you please help on this.
>
>
> Regards,
> Prabhakar V
>
> On Tue, Jul 11, 2017 at 1:48 AM, R0b0t1 <
> xxxxx@lists.osr.com> wrote:
>
>> I think his complaint is reasonable, however, though I have no idea
>> how to solve it. I would expect the OS (or hardware) to scale up the
>> processor frequency to be able to service the interrupt more quickly.
>>
>> Using DMA may solve the issue.
>>
>> —
>> NTDEV is sponsored by OSR
>>
>> Visit the list online at: http:>> lists.cfm?list=ntdev>
>>
>> MONTHLY seminars on crash dump analysis, WDF, Windows internals and
>> software drivers!
>> Details at http:
>>
>> To unsubscribe, visit the List Server section of OSR Online at <
>> http://www.osronline.com/page.cfm?name=ListServer&gt;
>>
>
></http:></http:>