Burn micronucleus to a Digispark board with a Mega2560 as ISP

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1

Hi there Guys,

I did this once, yet, now it is not really working.

I have the MEGA as an ISP - check
Connections are OK

This is the AVRDUDE command:
avrdude -P /dev/cu.usbmodem111201 -b 19200 -c avrisp -p attiny85 -Uflash:w:/Volumes/MM64/t85_default.hex:i -U lfuse:w:0xe1:m -U hfuse:w:0xdd:m -U efuse:w:0xfe:m

and this is what I get:

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.02s

avrdude: Device signature = 0x000000 (retrying)

Reading | ################################################## | 100% 0.02s

avrdude: Device signature = 0x000000 (retrying)

Reading | ################################################## | 100% 0.02s

avrdude: Device signature = 0x000000
avrdude: Yikes!  Invalid device signature.
         Double check connections and try again, or use -F to override
         this check.

Could you please help me out on what could be the issue?

2

I don't know anything about the Digispark.

This usually indicates bad / incorrect connections

You are aware that pins 10/11/12/13 on the Mega are not the SPI pins? Just asking as you did not show a wiring diagram.

And that is all I know.

3

Yes...
I know that the pins are different.
Yet, it turned out, I'd be able to program it without the programmer, since for a short period of time, it could be programmed.

Issue is that Arduino IDE can't see the small board.
I hate when I'm sooo dumm :frowning:

It should work, I literally just opened it :frowning:

4

You can't write to a digispark with ISP until you change the fuses with high voltage programming, because the reset pin is disabled and has been transformed into a normal I/O pin. ISP requires access to reset in order to work.

Here is an old post of mine that talks about using high voltage programming and then writing whatever bootloader you like via ISP.

The typical bootloaders are micronucleus and trinket. The only benefit of using a bootloader is you can disable reset (with a fuse setting) and get another I/O pin and yet still load new programs conveniently. Since you are armed with information about using high voltage programming, you can now choose not use a bootloader at all and set the fuses as appropriate to allow ISP programming, then disable reset to gain an I/O pin, and repeat high voltage programming in the future if you want to upload another program.

https://www.instructables.com/How-to-unlock-Digispark-ATtiny85-and-convert-it-to/