SPORT secondary data pin

Hi everyone, 

I'm working with the ADSP-BF706. I've configured the two halves of the SPORT1 as I2S and connected them to test as a loopback. I send from SPT1-A0 and receive on SPT1-B0.

I'm watching the output at SPT1-A1, but there's nothing on that pin. Are there some lib functions to use that pin?

Can I use SPT1-A0 as output and SPT1-A1 as input at the same time?

thanks a lot!