As a D2 owner, to confirm a couple of things: My D2 originally shipped with Anduril version number 2021-12-13-0135 as well. Model number 0135 was originally named emisar-d4sv2-tintramp, and is now named emisar-2ch, cf. https://toykeeper.net/torches/fsm/anduril2/MODELS. Over there, it is also specified as attiny1634.
Scrolling down https://toykeeper.net/torches/fsm/anduril2/, you will find the latest emisar-2ch version at the bottom, currently indeed anduril.2023-08-07.emisar-2ch.hex. Over there, you will also still find anduril.2021-12-13.emisar-d4sv2-tintramp.hex.
Usually, I am using ZFlasher AVR via mobile phone (Android), which is very straightforward, but I just checked with avrdude (on Linux), and I had no difficulties with pinging the device, backing up, and updating, while using the instructions over at https://anduril.click/flashing/avrdude.html.
I just checked with avrdude (on Linux), and I had no difficulties with pinging the device, backing up, and updating, while using the instructions over at https://anduril.click/flashing/avrdude.html.
SOLVED!
Thank you very much!
I was able to successfully ping and backup eeprom and hex file from my D2 with the following commands: