TMS320C6748: uart not recieving more than 16 bytes

Part Number:TMS320C6748

Hello

I am interfacing TMS320C6748 module with ESP8266 wifi to uart module. I am using processor sdk "pdk_omapl138_1_0_3"

When I send "AT+CWSAP=\"esp_ATS\",\"\",5,0" from TMS320C6748 to ESP8266

I read function reads only  AT+CWSAP="esp_AT which is 16 bytes only , If I try to read more than 16 bytes say 24 bytes I am getting '-1' as function return value. But expected result is ""AT+CWSAP=\"esp_ATS\",\"\",5,0   OK"

Through datasheet I could see the FIFO size is 16 bytes. Is this related  to FIFO issue. How could I read more than 16 bytes

Kindly suggest me to read more than 16 bytes in UART.

Thanks & Regards

Navaneetha krishnan