NuMaker audio playback

Revision:
15:8527899eb9d3
Parent:
11:f7e6e67bbb92
--- a/README.md	Fri Apr 20 14:46:08 2018 +0800
+++ b/README.md	Tue Apr 28 20:32:41 2020 +0800
@@ -36,6 +36,11 @@
 2. mbed toolchain "GCC_ARM"
 3. mbed compile
 
+Target board "NUMAKER_IOT_M487".
+1. mbed target "NUMAKER_IOT_M487"
+2. mbed toolchain "GCC_ARM"
+3. mbed compile
+
 Please note that to connect headphone and microphone or headset to hear the loopback result.
 
 Demo condition: