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Use Atmel JTAGICE3 w/ A-Star 328PB?

I have a A-star 328PB I am attempting to use with a Atmel JTAGICE3 emulator. I have the 6-pin vertical “ISP/debugWIRE” header on the A-star board connected to the emulator. However, using Microchip Studio, when I attempt to debug, I get a message saying that the DWEN fuse is not enabled, and do I want to use SPI to enable it. If I click yes, I get an error message saying “Failed to enable DW”. Also, I noticed there is a 0.1uF cap on the reset line of this interface on the A-star board, which Atmel/Microchip recommend against. Am I to infer that I cannot connect to this board using a JTAGICE3 (or presumably the later Atmel-ICE)?

EDIT: Found another post where someone talks about using the JTAGICE w/ the Orangutan board with an AVR Dragon and Jan from Pololu recommended removing that cap. The cap is C6; just not sure where it’s located on the A-star board and can’t seem to find a layout.


The A-Star 328PB Micro board does have a capacitor on its reset line (C6), but the other end of the capacitor goes to the D/R pin, not GND like on many of our older boards. As long as you leave the D/R pin disconnected, the other end of that capacitor will not be connected to anything so it should not interfere with debugWIRE. Also, please note that if you remove this capacitor, the D/R line will no longer work, so you will not be able to program the A-Star 328PB over serial using its bootloader as easily.

If you want to try removing it anyway, here is a picture with C6 circled:

Please let us know what you find out, and whether you have any further questions.