For those Radiuno suppliers that do not know; Macintosh users have significant trouble with the CH340/CH341 Arduino clones.
The Chinese vendor that makes that chip has done a very poor job writing drivers for the Macintosh. Many users report computer crashes and "kernel panics". The most suggested solution is to bypass an important security feature of the Mac called System Integrity Protection. This is definitely not recommended and requires some system level hacking that is beyond the average user. Some users report that the Chinese driver works for them; most do not. The latest driver from the Chinese (v1.4) does not require the system hack, but it does not connect to the Radiuno for me. I do still get occasional system crashes when trying to upload.
Apple supports just about all modern USB devices but it specifically does not provide drivers CH34x devices. Clearly this is a security issue for them. My understanding is that the CH34x devices were created to skirt royalties to be paid to the FTDI or Prolific intellectual property holders. For one reason or another, Apple does not support them. CURRENTLY (and despite claims to the contrary) THE AVAILABLE 3RD PARTY DRIVERS ARE UNRELIABLE.
I plugged the Radiuno into my Mac and tried to program it with the Arduino GUI and let loose with a few expletives. I knew immediately what had happened. I usually do my homework and avoid the CH34x chipsets in my Arduino projects, but Radiuno was not offered in another form and I neglected to check the chipset. (I still haven't found a spec for Radiuno that says what chipset it uses; clearly it is a CH340.)
I solved the problem by digging out a very old MacBookPro with an antique OS which does did not have the security feature and did support CH34x chipsets. While it is slow, it fortunately it runs the latest version of Arduino. My other alternative would have been to remove the CHxx Arduino Nano and replace it with an FTDI or Prolific PL2303 Arduino Nano... I may do that yet am not looking forward to it.
Please no more CH34x chipsets!