如何將IQ格式的值轉成字串用UART輸出到終端機上

http://read.pudn.com/downloads128/sourcecode/embed/549387/TMS320F28335/v101/DSP2833x_examples/sci_echoback/Example_2833xSci_Echoback.c__.htm

如這個程式

msg = "\r\n\n\nHello World!\0";
scia_msg(msg);

msg = "\r\nYou will enter a character, and the DSP will echo it back! \n\0";
scia_msg(msg);

可以在終端上看到Hello World!跟You will enter a character, and the DSP will echo it back!

那假設今天我有一個_iq x1=_IQ(1.125)

要如何設置msg=

讓我可以在終端上看到1.125這些字