Arduino nano 3.0 serial communication external power

Other Hardware 3rd Party Boards
1

Hi everyone,

I am currently making a project that requires an arduino to communicate over bluetooth. I was going to buy an arduino nano (then a bluetooth adapter) to do that. However, I saw on the arduino nano information page:

The FTDI FT232RL chip on the Nano is only powered if the board is being powered over USB. As a result, when running on external (non-USB) power, the 3.3V output (which is supplied by the FTDI chip) is not available and the RX and TX LEDs will flicker if digital pins 0 or 1 are high.

Is it only the LEDS that flicker? In other words: Can I use the serial communication when the arduino is not powered by usb?

2

RX and TX LEDs will flicker if digital pins 0 or 1 are high, Is it only the LEDS that flicker?

They flicker when Arduino board is receiving or sending info.

You will have no problem in your implication, Bluetooth is one of the easiest to use with uC's as it just acts as a wireless pipe connection where in you connect the RX and TX of Arduino to TX and RX of Bluetooth respectively and whatever you send over Serial.println(variable) etc is sent over the Bluetooth if its connected to the TX and RX , just remember that the flowing of data works byte by byte meaning that if you type GO then first the G will go and then after G is transmitted the O will go so you as a beginner just use the one bye variable for transmission like "o" and "f" to turn on leds for the starting and then start building up code to send full text strings over wireless.

your Bluetooth most probably will work at 3.3v if there is no breakout board for it (better check the datasheet of the component for it) and as you are using NANO you will be at advantage at this as you would need no level conversion. just power both from a 3.3v LIPO for instance.

3

Thank you,couldn't ask for a more complete answer. Just a little correction,the arduino nano 3.0 is 16mz so it runs on 5v so you can't use a 3.3v lipo battery. (unless you use a step-up ic :)).

4

You can always use a under clock mode use something near 8MHz or below depends over what implication you have!