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I designed a board and added a JTAG interface to program the built-in ATmega32 16U via an Atmel-ICE. I have already measured the individual pins of the JTAG with a multimeter and there is also 4.5 V at the decisive pins. I connected the JTAG interface to the microcontroller using the data sheet of the Atmel-ICE as follows:

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However, the programmer can't detect the ID of the controller, only the voltage of the pins.

Not ASMR
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    Please show the complete circuit diagram with all values of components. You could have put a dip socket under the mcu. Taking a look on the layout of and arduino could give some insight how to wire the crystal properly. – datenheim Feb 08 '23 at 08:16
  • @datenheim Thank you for the quick answer! Here is my full circuit diagram i posted it on the main question. – Not ASMR Feb 08 '23 at 09:25
  • Have you set efuses to external clock perchance? – winny Feb 08 '23 at 09:31
  • What's the main supply measured as? How do you know that the boost converter is working? Do you have the datasheet link for it? Why such extremely high resistance values to the feedback pin? – Lundin Feb 08 '23 at 09:46
  • @Lundin Thank you for your respond! The main supply is a 1.5 V aa battery. I know that the boost converter is working because i measured the voltage and its 4,5 V. According to the datasheet the resistance value must be that high to reach 5 V. Here is the datasheet of the boost converter https://cdn-reichelt.de/documents/datenblatt/A200/DS_MCP16251-2.pdf – Not ASMR Feb 08 '23 at 10:10
  • You expect 5V but measure 4.5V? At what voltage level does the brown out detect kick in? I glanced at the datasheet of the MCU and it seems you can set it to either 2.7V or 4.0V typical, but it can kick in as high as 4.2V. – Lundin Feb 08 '23 at 10:18
  • It cant be a problem with the voltage. I even tried to power it with an extern power supply that gives a consistent 5 V. The whole time i measured the voltage and looked it up in the osciloscope and there where no voltage drops at all. – Not ASMR Feb 08 '23 at 15:29
  • A physical pull-up resistor (10k) on /RESET is a good idea! Is the mcu totally new, so all fuses on factory default? Or has it been used elsewhere before? – datenheim Feb 08 '23 at 19:36
  • As a side-note: your layout of the step-up converter is far from optimum in general - I'm afraid every typical mistake was made (wide trace loops, bad placement of components, only component values followed etc.). It may work somehow at a first glance but I want to encourage you to follow the recommended component selection hints in the datasheet closely. And for layout tips you may learn from this [appnote](https://www.ti.com/lit/an/slva773/slva773.pdf?ts=1675802742694&ref_url=https%253A%252F%252Fwww.google.com%252F) for instance. – datenheim Feb 08 '23 at 19:46
  • @datenheim Thanks again for your help :) I used an old microcontroller first and also thought that maybe someone set the fuse bits there so i changed it to a completely new one. But it is still not working unfortunately. My circuit board is really not good indeed it was the first one I ve ever made so i am looking to the future to do better. – Not ASMR Feb 09 '23 at 06:37

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