Cannot find the USB serial device on macOS high sierra


(chris hulbert) #1

My HiFive1 just arrived, exciting!
I plugged it into my iMac via the micro-USB plug and can see the RGB LED cycling neatly, so it’s not DOA.
However if i do ls /dev | grep serial i cannot find any USB serial device corresponding.
I also checked in ‘about this mac’ > system report > USB and cannot see the device in the USB tree anywhere.
I have a super-cheap FTDI board that when i plug into USB it works every time.
I went to the FTDI website and downloaded and installed their macOS drivers, rebooted, but still can’t see it unfortunately.
Any tips?
Thanks all :slight_smile:


(chris hulbert) #2

This folder exists:

/Library/Extensions/FTDIUSBSerialDriver.kext

But if i do the following, it doesn’t appear to be loaded:

kextstat | grep FTDI

(chris hulbert) #3

I tried:

sudo kextload /Library/Extensions/FTDIUSBSerialDriver.kext

Then kextstat shows it being loaded:

kextstat | grep FTDI

But still doesn’t work unfortunately


(chris hulbert) #4

Fixed it! Used a different cable and works now. Maybe FTDI was browning out. Odd that the RGB LED was fine.
Oh well, onwards!


(Bruce Hoult) #5

Glad you found the issue.


(chris hulbert) #6

Might be fun for others to know: It comes up with 4 devices:

cu.usbserial-00006014A
cu.usbserial-00006014B
tty.usbserial-00006014A
tty.usbserial-00006014B

A didn’t do much, so i did the following (you might need to brew install picocom first)

picocom -b 115200 /dev/cu.usbserial-00006014B

Then pressed the reset button (red), and got this fun demo!

                    SIFIVE, INC.

         5555555555555555555555555
        5555                   5555
       5555                     5555
      5555                       5555
     5555       5555555555555555555555
    5555       555555555555555555555555
   5555                             5555
  5555                               5555
 5555                                 5555
5555555555555555555555555555          55555
 55555           555555555           55555
   55555           55555           55555
     55555           5           55555
       55555                   55555
         55555               55555
           55555           55555
             55555       55555
               55555   55555
                 555555555
                   55555
                     5

               'led_fade' Demo 



55555555555555555555555555555555555555555555555
5555555 Are the LEDs Changing? [y/n]  555555555
55555555555555555555555555555555555555555555555