EZ430 RF2500 Packet transmittion problem

Hi all:

I am using EZ430 RF2500 development kit, and try to set up a simple packet wireless channel between two target boards. According to application notes DN500.

I need to put data packet in TXFIFO, and then signal for transmittion by sending a STX strobe. Then I wait unitl the transimittion to be completed.

The code I wrote is:

while (!(P2IN&0x40));                      //GDO0 = 0x06;  and GDO0 is connected to P2.6 of MSPF2274. Wait until the sync word is transmitted.

while(P2IN&0x40);                          //Wait GDO0 to be reset, end of packet.

But the code gets stuck on "while(!(P2IN&0x40));

Can anyone help me out here?

Thank you