PORTS Forum

Ports and Interfaces => USB => Topic started by: kabanga on April 12, 2011, 07:06:47 am

Title: WinUsb_WritePipe(...) always returns "false"
Post by: kabanga on April 12, 2011, 07:06:47 am

Hello everyone,
I'm using the Axelson's WinUSB(C#).
A few days ago it was perfectly working.
Now it's not. I can't send data to the microcontroller.
While debugging my application I remarked that WinUsb_WritePipe(...) = bResult always returns "false". Why?
I didn't make any changes to the original Axelson's lib.
I have no idea what could have had happened.
Thanks for your help.

Regards

Title: Re: WinUsb_WritePipe(...) always returns "false"
Post by: Jan Axelson on April 12, 2011, 10:36:58 am

Reboot the PC. Reload the firmware. Use a protocol analzyer to find out what is happening on the bus. Try to read data.

Jan

Title: Re: WinUsb_WritePipe(...) always returns "false"
Post by: kabanga on April 13, 2011, 07:51:55 am

I reloaded the firmware. Then I sent data to the MCU. No data are sent.
And I see nothing in the monitoring window of "USB Monitoring Studio software".
What is puzzling for me is that I didn't change anything to my working code and PC.
Why did it suddenly stop working?

Regards

Title: Re: WinUsb_WritePipe(...) always returns "false"
Post by: Jan Axelson on April 13, 2011, 09:22:57 am

Be sure the host enumerated the device. Look for it in Windows Device Manager.

Jan

Title: Re: WinUsb_WritePipe(...) always returns "false"
Post by: kabanga on April 20, 2011, 09:56:35 am

It's working again, but I can't explain why .

Thanks and regards