build/tools/amebad/gnu_utility: Update README with more detailed guide
-# AmebaD Jlink Debug Function
+# AmebaD J-Link GDB Debugger
+
+### Preparations
+
+1. Prepare J-Link with firmware upgraded to V10.
+2. Install JLinkGDBServer.
+3. Set 'environment variable' for JLinkGDBServer if not done so.
+
+=============================
+
+### Connection
+
+Jlink AmebaD
+VCC -> 3.3v
+GND -> GND
+SWDIO -> DATA
+SWCLK -> CLK
+
+=============================
### How to use?
-1. Build TizenRT first and make sure 'tinyara.axf' is generated.
+1. Build TizenRT and make sure 'tinyara.axf' is generated.
2. Run 'jlink_debug.sh' in this directory.
-3. Then, enter any gdb debug command in the 'GDB Client' window.
+3. Enter gdb debug command in the 'GDB Client' window.
=============================
+
+
