I want to send signals via serial port using the JavaComm API classes on an Android device, and here is how I imagine it:
1- the Android device would be: Archos 3.2 which has android 2.2 and USB host mode.
2- include RxTx lib package with my Android app. and include RxTx native code using Android NDK.
3- a short cable which is usb-->serial.
Could you explain to me where I might face problems?
I just ported the JavaCOMM ( GNU RXTX ) library to the Android. Here is the link http://v-lad.org/projects/gnu.io.android/
You still might need to rebuild your kernel and maybe recompile the shared library for your environment. But this should get you started.