hci_cmd_task: hci0 command tx timeout

Hi

Ive been attempting to get PPP working so I can use GPRS over
Bluetooth with my mobile phone. It was quite simple and this page
(http://www.lugos.si/delo/slo/HOWTO-sl/ipaq-nokia-gprs.html) seemed to
work well.

I have seen a small problem however which is causing some issues.
After downloading some data (for example, use the Konqueror web
browser) there is the following message:

hci_cmd_task: hci0 command tx timeout

I have seen this problem before when I used the Waysmall board from
Gumstix. The problem is because there is no hardware handshaking on
the communication between the PXA and the Bluetooth module

I found this response on the web about the problem too:

>I always have had byte losses this problem, whatever bluetooth stack I
> use (OpenBT or BlueZ). On my PC, and on some other platform I tested,
> the flow control doesn"t work correctly (it is activated, you can see
> RTS/CTS change from time to time, but some bytes are lost). The bytes
> seem to be always lost by the PC, and not by the module. As there is no
> error-correction system in the HCI protocol, the PC won"t get the data
> as it should. The result can be various. But in any case, the stack will
> finnally not be informed of something (an inquiry result for example,
> or a negociation parameter), and won"t know what to do.
 
> I searched several weeks for a solution. However, I didn"t find a way to
> correct that problem.
 
> As a result, on those platforms, I have to use CSR bluetooth modules in
> BCSP mode. This additionnal protocol have error handling on serial line.
> This means I can"t use any other bluetooth module than CSR ones.The
> other solution is to use a module connected with USB.
 
Since the Bluetooth driver is protected it is not possible to change
some of the settings. I think one of the first things would be to
reduce the communication speed between the module and the PXA to half
the speed of what it is (3G phones communicate at max 321kbps)

Anyone else see this problem?

Regards

Thomas
Received on Tue Aug 30 2005 - 02:24:33 EDT