Windows XP doesn't recognize the USB connection

[JohnLook]

I compiled the example given in CCS, ex_usb_serial2.c, and I connected it in USB port, but I get a message that the device wasn�t recognized. I�m using PIC18F4550 and an oscillator of 48 MHz. The virtual COM# port isn�t created because Windows doesn�t recognize it and think that the device isn�t working. Could someone help me, please?

[Guest]

you need a inf file. i used the one from microchip and modified it. olso check vusb it must be 3.3v or it won't work. here is my inf file i use. change the pid &vid to match your file


; Windows USB CDC ACM Setup File


[Version]
Signature="$Windows NT$"
Class=Ports
ClassGuid={4D36E978-E325-11CE-BFC1-08002BE10318}
Provider=%MCHP%
LayoutFile=layout.inf
DriverVer=08/17/2001,5.1.2600.0

[Manufacturer]
%MFGNAME%=DeviceList

[DestinationDirs]
DefaultDestDir=12

[SourceDisksFiles]

[SourceDisksNames]

[DeviceList]
%DESCRIPTION%=DriverInstall, USB\VID_0461&PID_0033

;------------------------------------------------------------------------------
; Windows 2000/XP Sections
;------------------------------------------------------------------------------

[DriverInstall.nt] 7:44 PM 9/11/2005
CopyFiles=DriverCopyFiles
AddReg=DriverInstall.nt.AddReg

[DriverCopyFiles]
usbser.sys,,,0x20

[DriverInstall.nt.AddReg]
HKR,,DevLoader,,*ntkern
HKR,,NTMPDriver,,usbser.sys
HKR,,EnumPropPages32,,"MsPorts.dll,SerialPortPropPageProvider"

[DriverInstall.nt.Services]
AddService=usbser, 0x00000002, DriverService

[DriverService]
DisplayName=%SERVICE%
ServiceType=1
StartType=3
ErrorControl=1
ServiceBinary=%12%\usbser.sys

;------------------------------------------------------------------------------
; String Definitions
;------------------------------------------------------------------------------

[Strings]
MCHP="Microchip Technology Inc."
MFGNAME="Microchip Technology Inc."
DESCRIPTION="Communications Port"
SERVICE="USB RS-232 Emulation Driver"

[JohnLook]

Now Windows found my device and I installed the drive but when I connect my device Vusb goes to 3.30V and then it goes to 0.00V and the device is automatic disconnected. I don't know what is happening. Could you help me?

[MichaelW]

Hello,
I have the same problem. Is there any new awareness?
Michael

[Douglas Kennedy]

There are so many possibilities for error with USB you'd think it was built to provide lifetime employment for innovative software engineers. A USB sniffer ( I use snoopy pro) will help and of course there is limited support from USBview.
At least your system is staying up and not giving you the blue screen of death that makes it very difficult to proceed to a solution. Hopefully you'll see a packet go to and from your PC before Vusb goes down ( make sure you have the cap in place). If usb survives its journey through the registry and the driver is loaded then a quirky ( also know as software innovation) hand shake occurs before usb gets down to business. Be aware that PC usb ports can hang and often need a reboot to clear them. When debugging if a port appears hung I move on to another rebooting when the last usb port is hung.

[MichaelW]

Now it works. The reason was that I didn't use a connection sense pin and I didn't comment out the line "#define USB_CON_SENSE_PIN PIN_B2"