USB WrCmd takes too long time

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USB WrCmd takes too long time

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lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by dive on Wed Jan 27 00:18:06 MST 2010
Hello everyone.

I'm testing [COLOR=black][B]LPCXpresso[/B][/COLOR] board (LPC1343) with [COLOR=black][B]LPCXpresso[/B][/COLOR] IDE (2010-01-13 v3.2.1).
I add the USB connector same as the Getting Start (D+ is always pull-up).
Load the sample project 'usbcdc' and start debuging...

Then, it takes very long time in usbhw.c WrCmd function when USB cable is disconnected.

But it's not long when USB cable is connected.

Is it correct behaivor ?

If Yes, I don't want to wait so long time...
How should I do ?

Best regards
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lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by dive on Fri Jan 29 00:27:12 MST 2010
Hello everyone,

It may be solved the problem.
(It may be my mistake. sorry...)

I used long cable between LPCXpresso board and USB Connector.
This cable bring the noise voltage to VBUS ,
then LPC1343 judge the 'Plug-in' although USB cable is not plug-in.

It works fine with short length cable.
(It takes few seconds at the disconnecting the USB cable)


By the way, about USB_CONNECT (USB SoftConnect) function.
I check this pin (P0.6), then
     USB cable is not connected.     Low -> High -> Log -> High ....      
     USB cable is connected.           always Low

Is it correct behaivor ?

Secondary function VBUS(P0.3) and SoftConnect(P0.6) are enabled.

Best Regards.
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