Problems uploading to Arduino mini Pro from Arduino Uno

Hello,

I'm a student who likes to try new things with Arduino.

For my current project, I'm using a Arduino pro mini. I do not have a Usb UART converter so I used a Arduino Uno to program the Pro mini. Unfortunately with no succes.

I tried everything, all settings in Arduino, all schematics, nothings works... Also there is always a green light on (that's good) but there is also blinking (quite fast) a red light. I do not know what that means..

Anyone who could help me? Thank you a lot!

Koen

Please provide a detailed description of how you did that. Including:

  • The exact wiring connections between the Uno and Pro Mini
  • The exact steps you took on your computer

Please provide a detailed description of what you mean by "no succes". Include the full and exact text of any error or warning messages you encountered.

It is most likely nothing to be concerned of. There are several LEDs on the Pro Mini:

  • Power - on whenever the board is connected to a power source
  • built-in - This LED is connected to Arduino pin 13. Its behavior depends on the sketch that is running on the board.

Neither of these are used as error indicators and the red color does not have any significance whatsoever.

The board comes with a program installed that blinks the built-in LED. Once you have uploaded your first sketch it will do whatever the sketch makes it do.

Hello,

I'm a student who likes to try new things with Arduino.

For my current project, I'm using an Arduino pro mini. I do not have a Usb UART converter so I used an Arduino Uno to program the Pro mini. Unfortunately with no succes.

I tried everything, all settings in Arduino, all schematics…

Is there anyone who could help me, thank you!

Koen

We know the published diagrams are correct, so you may have just wired it wrong. Please show us images of your actual hardware connections.

Make sure you have the correct pro mini selected in the boards menu, Click upload on the IDE, when the sketch size is shown, tap the reset on the pro mini.

I hope you can see all the colors clearly.
The light under "9" is blinking red.

All looks fine,

  • 'pro or pro-mini' is the board you should select
  • Connecting RST to GND on the Uno disables anything running on the Uno, that is fine of course because we don't want any interference from it. I normally just upload 'blink' (or a version of that) because the Uno can be functioning but just not be using the Serial port (or pins 0 & 1). Some people take the MCU out of the board, but it is not impossible to damage the physical pins of the 28 dip package.
  • The thing you may have missed is that the Pro-Mini also needs to be reset when the attempt to upload is made. before i automated it i would hold down the (red) reset button on the Pro-Mini, and release it the moment the IDE would show the compiling results.

When i say 'automated the process, let me explain. So i would start with uploading 'Blink' onto the Uno. Disconnect RST on the Uno from GND, and connect RST on the Uno to RST on the Pro-Mini instead. The DTR on the the Uno is enough to reset the Pro-Mini when the time has come (for at least, Uno's and pro-Mini's come in many variants by different manufacturers)

Still not working, can it be that the Arduino mini pro is dead because of the blinking red light?

The blinking red light tells us it has blink uploaded to it! Just spend a few £$ or whatever and just buy a USB to TTL adaptor.

What board do you have selected (screenshot)
And the error within </> code-tags.

I selected "Arduino Pro or Pro mini"
And this is the error:

Ok, so you haven't changed the wiring ? but you have held the red-reset button and release after the compile completes. Good.
Hey hold on, is it a 3.3v board ?
In that case you should change the processor speed to 8MHz. Have you done that ?

COM1 is usually not the Arduino. Does it disappear from the tools options if you disconnect the setup from the PC?

From the screenshot in post #3, yes :wink:

But there it is connected to 5v ...

A 3.3V ProMini will happily run on 5V; the part I was refering to in the screenshot shows the 3.3V/8MHz version selected.

image

Yeah yeah i saw, i didn't catch on to that until i saw it connected to 3.3v on the pic in #7
I suppose the crystal defines the speed really (though you can run 16MHz on 3.3v of course)
Anyway looking at the picture again, i see that bad soldered connections are not an unlike cause.

Choosing com port 1 is the most likely issue, I have NEVER seen an Arduino on com 1, ever in over 10 years, also, the selected voltage DOES matter as the 2 different bootloadrs run at different speeds!

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So true. COM1 is usually in use by a semi-internal component. Could be bluetooth or something. The Uno should show up under a different number usually, and this number may not be the same depending on the hub used.

As a setting yes, but you can power an 8MHz Pro-Mini with 5v no problem. (vice versa not 16MHz needs 5v) The setting is the speed.

Yeah, unplug the Arduino and see if it's still there.