Sparkfun Arduino pro mini


I have one of the older Sparkfun arduino pro mini boards with the 4 connections (grnd, power, tx and rx). Works great.

I recently purchased the Sparkfun:

Arduino Pro Mini 328 - 5V/16MHz and FTDI Basic Breakout - 5V

When I connect the above to the USB cable the red power LED on the Arduino comes on, however, the green LED (pin 13) fast blinks. Pressing reset pauses the blinking while reset is pressed and once released the fast blinking starts again.

If I try to download, the TX light on the FTDI blinks, but ultimately the download fails.

I made sure the grn and blk of the boards match each other.

Any thoughts on this?

Thanks Phil

How are you connecting the board to the cable? I found I had nothing but trouble trying to do what they showed on the example page where you just stick the pins in the holes and kinda lean it on there.

Ever since I soldered some pins into place though, it works perfectly.

Also, it may help to know that you don't need to press the reset button to program it. You just need to remove power. So if you pull the pins out, then stick them back in, and click the upload button without too much delay, your program should upload. But if you move the board and accidentally break the connection you'll probably have to try again. It's finicky doing it that way.


thanks for the response. I have a header soldered in.

Well, after pressing the reset, pin 13 LED, should go dark, but instead it fast blinks.

Actually, let me rephrase that.

It's not neccrssary to remove power to upload a sketch. But if you have a poor connection or your pc doesn't want to reset it when you go to upload a new sketch, then removing the power is one easy way to reset it so you can upload a new sketch.

The problem with pressing reset is if you don't have header pins soldered in there, you're probably gonna end up breaking the connection anyway when you try to hit reset, so you might as well not bother with it.

I tested on my mini, and when I press the reset button, the green led blinks only once before the program starts, regardless of whether I hold it down for a little while or not.

When I plug it into the usb cable for the first time however it blinks for a couple seconds before the program executes.

I don't know if that's of help to you, but it seems like normal behavior anyway.