Howdy, I'm new! 
I'm trying to troubleshoot a AVR Pocket Programmer. It worked previously with this laptop about a month ago. (But it traveled through the mail between now and then.) When plugged in the pwr, stat1, and D- lights light up steady (the D+ blinks briefly as if it's trying to do something then stops). It does not show up in Arduino under Tools>Port, in Network Preferences, or with ls /dev.
In Console it says "kernel IOUSBHostDevice: family specific matching fails" at least a dozen times.
It shows up in system information as:
Vendor-Specific Device:
Product ID: 0x0c9f
Vendor ID: 0x1781
Version: 1.04
Speed: Up to 1.5 Mb/sec
Location ID: 0x14130000 / 26
Current Available (mA): 500
Extra Operating Current (mA): 0
What I've Tried:
I've tried two Macbook Pros, one with Sierra, the other with High Sierra with 2 different USB cables.
... another Arduino device, it shows up fine
... several USB hubs
... a PRAM reset
... Target Power & No Power (switch on board)
... unplugging everything else and removing all the non-essential networks in System Preferences
... reciting The Tempest in Klingon (ok I didn't actually go that far yet)
What else can I try to diagnose/fix this? The latest version of USB Prober refused to install. Finding a windows computer to test it on is my next step. Is there a way to tell if the board has gone defective with a multimeter?