Programming Arduino Mini using Uno Rev3, enough info about it but...

So there is a lot of info on the internet about programming an Arduino Mini using an Uno Rev3, but they all take the ATmega chip off the board when they do, but I can't exactly find out why they do it.

The reason why I'm asking is because I have one Chinese copy Arduino Uno (I got it from my University), and I'd like to use that one (temporarily, until I get my USB to Serial converter) to program an Arduino Mini (Original, no Chinese copy), but it's not that easy to take off the ATmega(-ish?) chip on that one, and I think putting it back would be even harder...

If it's taken out just to make sure it doesn't get flashed, I don't care because I don't use this board... Or is there another reason?

If you don't take the chip off, you will be talking to that chip not the Pro Mini.

If you want you can try grounding the reset pin (on the uno) which should have the same effect but then you will need to press reset (momentarily) just before upload.

ChilliTronix:
If you don't take the chip off, you will be talking to that chip not the Pro Mini.

If you want you can try grounding the reset pin (on the uno) which should have the same effect but then you will need to press reset (momentarily) just before upload.

I was afraid of that, pretty logical tough...

But your solution does sound reasonable, it's just a temporary solution until I get the right stuff...

Let us know how you get on.

Will do, I just placed the order for an Arduino Mini, it might still make it here by/at the end of this year :slight_smile:

I thought you had the Pro mini but no usb to serial converter? Why not order one at the same time? (Where in the world are you? I suspect you can get them from the same place as you got the Pro mini)

SparkyRih:
So there is a lot of info on the internet about programming an Arduino Mini using an Uno Rev3, but they all take the ATmega chip off the board when they do, but I can't exactly find out why they do it.

The reason why I'm asking is because I have one Chinese copy Arduino Uno (I got it from my University), and I'd like to use that one (temporarily, until I get my USB to Serial converter) to program an Arduino Mini (Original, no Chinese copy), but it's not that easy to take off the ATmega(-ish?) chip on that one, and I think putting it back would be even harder...

If it's taken out just to make sure it doesn't get flashed, I don't care because I don't use this board... Or is there another reason?

If you use arduino as ISP you dont have to remove atmega to upload to mini.

ChilliTronix:
I thought you had the Pro mini but no usb to serial converter? Why not order one at the same time? (Where in the world are you? I suspect you can get them from the same place as you got the Pro mini)

I knew this question would come along... The store that I bought all of my genuine Arduinos does sell the genuine Mini, they have pretty much everything you need for any of he Arduinos (like sensors, all kinds of sensor brackets, shields, all kinds of motors, Lilypad thingies, robot platforms (ranging from €10 to €300) etc. etc.).... But guess what, no serial adapters!

I bought the serial adapter somewhere in China along with a bulk of other stuff because it's waaay cheaper, it should take about a week to get here to The Netherlands...

The mini was shipped today, so I'll most likely get it tomorrow...

ChilliTronix:
If you don't take the chip off, you will be talking to that chip not the Pro Mini.

If you want you can try grounding the reset pin (on the uno) which should have the same effect but then you will need to press reset (momentarily) just before upload.

So I got the Mini 05, this image shows how some guy connects his Uno to the Mini 05 (but also taking off the chip), so you say that I should try pulling the reset of the Uno to the ground of the Uno?

http://draganbjelic.com/wp-content/uploads/2012/12/Ardu_Steckplatine.jpg

SparkyRih:
So I got the Mini 05, this image shows how some guy connects his Uno to the Mini 05 (but also taking off the chip), so you say that I should try pulling the reset of the Uno to the ground of the Uno?

http://draganbjelic.com/wp-content/uploads/2012/12/Ardu_Steckplatine.jpg

Try if it works. No component should be damaged by doing that. But I dont know if it works because atmega16U2 might be connected to reset and that wouldnt allow to upload.

Tie the reset of the Uno to ground and press reset on the Pro mini just before upload. Let us know how you get on.

oh, and don't connect the resets together as the Uno one needs to be permanently grounded during the operation, whereas the Pro mini only wants to be reset just as the upload starts.

OK, let’s see if we can get this sorted.

There are two ICSP headers on the UNO (R3) board, one for the 16U2 USB to TTL converter, and one for the mega328. By placing a jumper between pins 5 and 6 on the latter one, you disable the mega328 in which case all its I/O pins are open and you can connect your Pro Mini TX and Rx to pins 0 and 1 to communicate with the USB to TTL converter. There is no interaction between reset on the mega328 and reset on the 16U2.

So why would there be a suggestion to remove the chip?

Well,

If you remove the chip, you can connect the reset pin (not “GRN”) on the Pro Mini to RESET on the UNO and the auto-reset will work perfectly well. Clearly if you have instead grounded RESET on the UNO in order to disable the MCU, you cannot do this and will have to manually reset the Pro Mini using its own reset button, pressing it momentarily when you see the “Done Compiling.” message in the aqua (coloured) bar below the code window in the IDE.


I am sure SparkyRih looks nothing like the avatar.

Paul__B:

I am sure SparkyRih looks nothing like the avatar.

To be fair, neither do you or indeed I look like our avatars....

Here we go:

I flashed a for loop that simply counts up with some delay and prints it over serial, and I get the data back in the serial monitor, and when I disconnect the Arduino Mini 05 (not the Pro, it's an ATmega328, 2KB memoery, 1KB EEPROM 32KB flash), and read the Uno over serial it doesn't print anything... So that pretty much means that it is working perfectly! :slight_smile:

Thank you!

(And no, I don't even get close to my avatar :D)