Problem uploading to Z-Uno on Arduino 1.8 on MacOS

[jemenake]

Background:
This is my second Z-Uno. The first one, I had success with, so I bought another one about a year ago, and I haven't tried working with it until now. I pulled it out of the box, plugged it into my MacBook (MacOS 12, Arduino IDE 1.8.13) and I tried uploading the "Simple Sensor" example on the Z-Uno website. It compiles fine, but, when I try to upload it, it displays "Syncing with Z-Uno ('RST' btn?)".

Code: Select all

Sketch uses 7388 bytes (18%) of program storage space. Maximum is 40704 bytes.
Global variables use 992 bytes (12%) of dynamic memory, leaving 7100 bytes for local variables. Maximum is 8092 bytes.
Openning port                            ..............................       OK
Syncing with Z-Uno ('RST' btn?) [*  ]    ..............................

I've used some Arduinos which needed their Reset button pressed in order to put them into upload mode, but I don't recall needing to do this with my other Z-Uno. I tried it, anyway, and all that did was cause the uploader to rapidly fail about 90 times. Suggestions?

[jemenake]

I was able to resolve the problem, somehow. I tried Arduino IDE 1.8.13, and that gave me warnings about a corrupted S2 key, and it also advised me to update the boot loader. I was able to do that, and I'm able to upload sketches.