rockminer: Bugfix: must specify a baud rate (maximum of 115200) to get a read response
Potentially a Silicon Labs driver on Mac OS X - not an issue on Linux
Tried (and failed) baud rates: 128000, 153600, 230400, 256000
Merge pull request #487 from nwoolls/bug/rbox-nodetect-osx

rockminer: Bugfix: must specify a baud rate to get a read response on OS X