I just plugged in a new Leonardo into my computer and the L-Led is blinking constantly. It looks like 3 quick blinks and then a longer blink.
Loading a sketch to the Leonardo, generates the following message:
avrdude: usbdev_open(): did not find any USB device "usb"
The Leonardo shows up in the device manager as being on COM8.
I have tried:
Uninstalling and reinstalling the Arduino driver
Using the Leonardo driver from the 'Old Arduino Drivers' folder
Resetting the Leonardo
Restarting my computer
Using a different USB cable
None of this has had any effect... still blinking 3 quick blinks and a 4th longer blink
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So, after much frustration, I got it to work. Here's how:
Selected AVR ISP from the Tools>Programmer menu and then tried the upload. Leonardo reset, and I noticed that a bootloader was installed on COM9. This time the sketch loaded and all seems to be working.
My question is: What was wrong in the first place?