AT89c5131 can not be detected by xp

[shendu]

can anyone help me? the osillator can work, there are signal on ALE pin, I make the pcb by myself, but we i plug the usb bus, the xp system says that it can detect it ,"unknown device"

is it the problem of at89c5131 (don't have a bootloader ) or the problem of my schematic. wish a expert to help me?

my email: wxzhao@yahoo.cn
can anyone help me?

Added after 19 minutes:

this is my design

 

[pranam77]

Presumed that the micro is programmed with the firmware, please check the D- and D+ connections connected on the PCB. IF interchanged, nothing will be detected. Too see you get proper 5volts to the microcontroller. Goodluck.

 

[GetDeviceInfo]

'unknown device' popup means that xp has detected it, but can't find a driver.

What are you expecting?. If you load up Atmel's flip, try to make a connection, it will repeatedly open a DOSbox, which queries the USB port looking for the device. A bootloader sequence on the device should then complete the connection.

 

[shendu]

the question is when i plug in the usb bus, flip is set up, but the pop up not occur, xp don't tell me to load the driver

 

[pranam77]

Your schematic posted above shows Pin2 of USB as D- whearas it shud be D+ as compared to other USB schematics. Try inter chnaging these. Good luck.

 

[GetDeviceInfo]

Ok, I tried it and I'm wrong. A bootload sequence should prompt the dosbox, then flip will connect.

better follow the other suggestions. Sorry.