Can an Arduino control/power a USB external modem?

Forum 2005-2010 (read only) Hardware Interfacing
1

Can an Arduino control and power a USB external modem?

I want to connect an Arduino (powered by a wall wart or a battery) to an external modem, then connect the modem to a conventional telephone line so that I can dial up the modem from my computer and receive data from the Arduino. My basic question is what's the easiest and cheapest way to do that. I started this project some time ago and am just now getting back to it.

Originally, I had planned to use a serial modem to do this, but then learned that I might need a TTL to RS232 converter to use a serial modem. I'm not sure how to do that, although I guess it's not too difficult.

In any event, then I received my Arduino Duemilanove (my first one !!) and realized that it is a USB device. Now my question is whether the Arduino could both power and control a USB modem. eBay has them for around $15. I'm particularly concerned about powering the USB modem from the Arduino. Does an Arduino with a wall wart have enough power to do that? and does a USB modem use AT commands like serial modems used to?

If not, then what IS the easiest and cheapest way to connect and control an external modem from an Arduino? Thanks in advance for any suggestions.

2

If the modem is a USB Slave, then it must be connected to a USB Master. The Arduino cannot act as a USB Master. So the simple answer is "no". It's much simpler to use an RS-232 modem (a "PC external modem") and connect it to the Arduino's serial port via a TTL-to-RS232 convertor (MAX232 chip).

3

Thanks Anachro, I'll work at the serial modem option with a MAX232.