I did use Ubuntu 16.04 (32 Bit) with Arduino-IDE 1.8.5 (also 32 Bit) an those cheap Nano-Clones with CH340-Chip. This configuration worked without any problems.
Recently I changed Ubuntu 16.04 to 64 Bit. I also installed Arduino-IDE 1.8.5 for 64 Bit Linux. Now the IDE was not able anymore to upload sketches to the Nano-Clone. I always get those error-messages:
... avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0x00 ...
When checking out older IDE releases I found, that IDE 1.6.1 (64 Bit) and previous works fine with Ubuntu 16.04 (64 Bit) an Nano-Clones. IDE 1.6.2 an newer don't work.
Does anybody know how to fix this bug to use IDE 1.8.5 with 64Bit Ubuntu and CH340-Nano-Clones?
Processor : 2x AMD Phenom(tm) II X2 550 Processor Memory : 3782MB (1490MB used) Operating System : Ubuntu 16.04.4 LTS Kernel : Linux 4.13.0-36-generic (x86_64)