Hello all, Yesterday, I posted an issue (now resolved) which ultimately proved to be incompatibility between the FreqMeasure library and an Atmega328 U (on a breadboard) that I received in error (I ordered 328P-U). In the process of trying to solve my issue, I tried upgrading from IDE 1.8.10 to 2.1.0. (Mac Os). Now when I try to upload using programmer (Arduino as ISP), I get the classic: "avrdude: Yikes! Invalid device signature. Double check connections and try again, or use -F to override this check. Failed programming: uploading error: exit status 1 I switched to IDE 1.8.10 and am able to upload to the breadboard, no problem. It had nothing to do with my code - I tried uploading Blink without delay and other simple sketches from the examples folder. Clearly, I'm missing something....does it have anything to do with Command Line Developer Tools? I couldn't install it because it's too huge and I don't have the HD space at the moment. Thank you in advance! Jeff

This message has nothing with the code. This is result of uploading, the code is already successfully compiled. The problem is that the signature obtained from the target MCU is not equal to expected signature. The most frequently it is wiring problem, so double check connections and try again and just ignore -F advice. It is good to know what was obtained from target MCU. All bytes are zero? There is no connection, missing wire, bad connection. 0xFF's? Shortage on wire. Something else? This could be a problem to resolve. It depends. Can be for example different MCU like ATmega328P and ATmega328. They have different signature.

I imagine if it was a wiring issue, upload wouldn't work with IDE 1.8.10. My post was overly verbose. The distilled version is that when I upload from 1.8.10, it works perfectly. When I try to upload the same sketch, or any other, from IDE 2.1.0, I get Yikes!

Maybe it is some bug in this version. Here was something in 2.0, maybe similar: [image] Failed Upload Ide 2.0 IDE 2.x I continually get an error when trying to upload with the new IDE. There are no compile issues and the code uploads fine with the old IDE. Occasionally, the 2.0 will upload. This typically happens after closing and reopening the app and using the tools menu to select the port and board instead of the automatic drop down menu. Currently, the port options list old ports that are now not connected. Plugging in to a new port does not updated the port list. Below are 2 different error messages that…

Hello all, I've been having ATmega 328 issues. First thing first, with the ones I purchased before my problems arose, I have no issues. Sketches upload fine, so there is nothing wrong with my USB cable or any other connections. My workflow for years has been creating sketches and uploading them via an Arduino Uno R3 to ATmega328s on a breadboard using "upload using programmer". What I expect is to be able to select Arduino as the board, which I've been doing for years. With the last 3 purchases of these microcontrollers however, one which was too long ago to return, I get the "Yikes" invalid device signature error. The last 2 purchases I made with this problem are these, from Jameco, purchased in this order: https://www.jameco.com/z/ATMEGA328-PU-Atmel-Microchip--IC-ATMega328-U-8-bit-Microcontroller-32KB-Flash-DIP-28_2139111.html https://www.jameco.com/z/ATMEGA328P-PU-Atmel-Microchip--ATmega328P-PU-AVR-Microcontroller-8-Bit-20MHz-32KB-DIP-28_2303943.html In both cases, I could not get a sketch to upload using Arduino as ISP/upload using programmer due to the Yikes! error. I returned the first order, and I'm about to return the latest one. In order to get these to work, I had to scour the internet to find a compatible board to install. MiniCore ATmega328 worked, but as with these 2 boards from Jameco and my previous purchase before that, they are unbelievably slow. For example, if I send a byte of data over Serial and tell it to turn on a pin when received, it takes a FULL SECOND for the pin to turn on, whereas with the older 328s, the latency is imperceptible. I've posted here before about this, but haven't gotten any response, and I've had almost no luck on Google. I'm baffled, and I'm running out of properly working 328s. Has anyone else had this issue? Is there something I'm missing? If I put an ATmega328 on a breadboard and use UNO as the programmer, should I not be able to select "Arduino Uno" as the board rather than having to go search for a compatible board to install? These are absolutely useless.

Assumption is you are following this method or similar ? Gammon Forum : Electronics : Microprocessors : How to make an... Gammon Forum : Electronics : Microprocessors : How to make an Arduino-compatible minimal board Or Gammon Forum : Electronics : Microprocessors : Atmega bootloader programmer Gammon Forum : Electronics : Microprocessors : Atmega bootloader programmer

Hi @JB8256 [image] JB8256: I get the "Yikes" invalid device signature error I'm going to ask you to post the full output from the upload when in verbose mode. :red_exclamation_mark: NOTE: These instructions will not solve the problem. They are only intended to gather more information which might provide a clue that eventually leads to a solution. Please do this: Select File > Preferences from the Arduino IDE menus. Uncheck the box next to Show verbose output during: ☑ compilation Check the box next to Show verbose output during: ☐ upload. Click the OK button. Attempt an upload, as you did before. Wait for the upload to fail. You will see a "Upload error: ..." notification at the bottom right corner of the Arduino IDE window. Click the COPY ERROR MESSAGES button on that notification. Open a forum reply here by clicking the Reply button. Click the icon on the post composer toolbar. This will add the forum's code block markup (```) to your reply to make sure the error messages are correctly formatted. [Code tags icon on toolbar] Press Ctrl+V. This will paste the error output from the upload into the code block. Move the cursor outside of the code tags before you add any additional text to your reply. Click the Reply button to post the output.

I've done this as well. This: ATMEGA328-PU is NOT the same chip as in the Uno. The ATMEGA328P-PU is, however, correct. If you use "upload using programmer", that is the ICSP method, to upload a sketch directly, you have to use AVRDUDE to set the fuses correctly on a factory fresh chip. If you burn a bootloader onto the chip, the fuses are set *correctly during this operation. That you have succeeded in uploading a sketch indicates that the chips are OK. (*) well, nearly correctly. If you upload a sketch directly using a programmer, as opposed to uploading via a bootloader, you also need to unset the BOOTRST fuse otherwise you get a nasty surprise if the sketch is so large that it strays into the bootloader area. From your description, it sounds like the "divide by 8" fuse is set as it would be in a factory condition chip.

Nick Gammon's chip signature detector linked to on the Minimal breadboard Arduino page with the rest of his software.

I've posted more than once here relating to issues I've had with ATmega 328s, but have gotten no response, so somehow I think I'm on an island waaaah......I guess it hasn't happened to anyone else. I embed these in musical instruments. I connect mine, on a breadboard, to an Arduino Uno. I would like to buy ATmega 328P-U units that will be recognized when I select "Arduino Uno" as the board. The ones I've been buying give the dreaded "Yikes!" error, and the only way I've been able to circumvent that is to install the MiniCore boards. The problem is, they are SLOOOOW - i.e. if I tell it to turn on an LED after receiving a byte on the serial in port, it takes as long as one second to respond. If I have a 328 that works when selected as an Arduino Uno board, it seems to work fine. I'm so baffled by all this. I've been doing this stuff since 2014, and now I'm running out of 328s that work acceptably. The last 2 batches I bought were from Jameco, and I returned them all. Any recommendations as to where to purchase these?

[image] JB8256: The problem is, they are SLOOOOW That makes no sense. The chip runs at the fuse-selected clock speed or external crystal frequency, unless you forgot to clear the CKDIV8 fuse bit (set by default for new parts). Digikey has the genuine part in stock.

Yikes! while trying to upload using programmer

Development Tools Uploading

Budvar10 May 7, 2023, 7:06pm 4

Maybe it is some bug in this version.
Here was something in 2.0, maybe similar:

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Yikes! while trying to upload using programmer

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