[RS90/GKD350H] fix and tune to NP21kai 2
@@ -333,6 +333,26 @@ $ make -f Makefile21.gcw0 buildopk
1. Transfer np2kai.opk to /media/apps/ .
2. BIOS files should locate in ~/.config/np2kai .
+### Dingux series (RS90 GKD350H)
+
+##### Build
+1. Change directory to sdl2.
+```
+$ cd NP2kai/sdl2
+```
+2. Make.
+```
+$ make -f Makefile.gkd350h
+```
+or
+```
+$ make -f Makefile21.gkd350h
+```
+
+##### Install binary
+1. Transfer np2kai.opk or np21kai.opk to /media/apps/ .
+2. BIOS files should locate in ~/.config/np2kai (or np21kai).
+
#### libretro port (Windows/Linux/macOS)
##### Install tools
