USB serial driver(ftdi): there is error in receive data
 

when it is too short that time between two data sending form device to pc, the second data is lost.

I was using a wireless net card. the card connect to pc through USB. when it's connected, the usb is probed as two devices: one is ftdi,the other is cdc-acm.

I can use it to make one call. when I use it to make another call while hold the first call. the application cann't get the wright At respond.

it's like this (I cann't remeber the exact form):
AT+CLCC "10086"
AT+CLCC "1360000000" OK

the problem is I cann't receive :AT+CLCC "1360000000" OK.
but in the log from the card, it had sent it out.