Control a serial device (like usb printer) from an Android app

I have two questions about Linux Android.

In the documentation it says:

"Android Debug Bridge (adb) is a versatile command line tool that lets you communicate with an emulator instance or connected Android-powered device."

And apparently there is a way to send a command to serial port (USB) from ADB (Android).

So, I need to send commands (like AT commands) from android device to 开发者_如何学Cusb device (printer)

1) The ADB will be present on a real device with android?, which version?

2) is there another alternative?

Thanks in advance

And apparently there is a way to send a command to serial port (USB) from ADB (Android).

Not that I am aware of.

The ADB will be present on a real device with android?

adb is a program that is part of the Android SDK. It runs on your development machine. It does not run on the emulator. It does not run on the device.

is there another alternative?

Use the USB APIs and the Open Accessory Development Kit, perhaps.