FTD2XX.DLL - two devices simultaneously

[letibell]

witrh Vb2005 Im'm using two FTDI devices programmed to send data as SPI channels, thanx to FTD2XX.dll . I can select one or the other, and send data as I like, but I wonder if I can use t hem SIMULTANEOUSLY.
I'm using TimeSetEvent to repeat data ad libitum ,selecting one of the 2 devices, but I'm not sure I can send data simultaneusly on both the 2 channel without interrupting transmission. Did anybody face a similar problem?
any suggestion?

 

[btbass]

Dont those devices have tx and rx buffers?
Couldnt you rapidly fill the buffer of one and while its transmitting, fill the buffer of the other and keep filling alternate buffers.