How to transfer data through UART

Question

Hi, 
 I used nrf51822- EK board. 
 GATT - s110 6.2.1 softdevice 
 I transfer data through UART for nrf51822-EK(PCA10001). 
 But this time. I used nrf51822 smart beacon kit(PCA20006). 
 PCA20006 is received data through UART. 
 But PCA20006 is not transfer data through UART. 
 PCA20006 UART 
 rx ------------------------- tx (OK) 
 tx ------------------------- rx (XX)<-- this problem... 
 I guess NRF_UART0->EVENTS_TXDRDY not set 1. 
 So. How to solve this problem ?

Susheel Nuguru · Accepted Answer

you did not mention if you have connected your beacon to PC or somthing? does does it get RX characters and where does uart put TX charaters?
Also I do not understand what this below means 
 PCA20006 UART
rx ------------------------- tx (OK)
tx ------------------------- rx (XX)<-- this problem...
 
 you might as well try to disable flow control and see if that works