need NPAPI,PPAPI or other?

i'm finding some solution to develop the Packaged App (or extension) for Chrome OS(chromium os).the extension will be access serial port to send AT command for SMS or Call function.

first, i find the NPAPI,But it not support in Chrome OS (right?) . So, maybe the PPAPI and Native Client ? if i开发者_开发问答t's the key, i will look deep in them.

please give me some advice . thanks ~

NPAPI is supported by Chrome OS, but there is no way to install it, you can create Chrome extensions that uses NPAPI plugin for windows, linux, mac, but not for Chrome Os. NPAPI plugins must be preinstalled by vendor as I know, so you can't use it. If you want to use native code you need to look to Native client, but as NaCl is sandbox for native code I am not sure you will be able to access low-level hardware within it.

PPAPI only, NPAPI us NOT supported: https://sites.google.com/a/chromium.org/dev/developers/design-documents/aura-desktop-window-manager