> #devc-serusb -d did=0xda70，vid=0x0403 

First, you don't want a space between the comma and "vid".

Second, I think you'll need to also specify the module to use, as 0xda70 is not a known device:

#devc-serusb -d did=0xda70,vid=0x0403,module=ftdi 

Modules should include: prolific mcs7720 uc864e ftdi wireless_modules generic