I have just programmed a new micro, loaded the basic blink code in it. After that neither my laptop, nor my desktop sees it anyway with the following usb error:
Fri Apr 1 14:32:01 2016] usb 1-2: device descriptor read/64, error -62
[Fri Apr 1 14:32:01 2016] usb 1-2: device descriptor read/64, error -62
[Fri Apr 1 14:32:02 2016] usb 1-2: reset full-speed USB device number 8 using ohci_hcd
[Fri Apr 1 14:32:02 2016] usb 1-2: device descriptor read/64, error -62
[Fri Apr 1 14:32:02 2016] usb 1-2: device descriptor read/64, error -62
[Fri Apr 1 14:32:02 2016] usb 1-2: reset full-speed USB device number 8 using ohci_hcd
[Fri Apr 1 14:32:03 2016] usb 1-2: device not accepting address 8, error -62
[Fri Apr 1 14:32:03 2016] usb 1-2: reset full-speed USB device number 8 using ohci_hcd
[Fri Apr 1 14:32:03 2016] usb 1-2: device not accepting address 8, error -62
[Fri Apr 1 14:32:03 2016] usb 1-2: USB disconnect, device number 8
[Fri Apr 1 14:32:03 2016] usb 1-2: new full-speed USB device number 9 using ohci_hcd
[Fri Apr 1 14:32:04 2016] usb 1-2: device descriptor read/64, error -62
[Fri Apr 1 14:32:04 2016] usb 1-2: device descriptor read/64, error -62
If I push the reset button on it it comes back a bit then disappears again:
22620.495256] usb 1-2: New USB device found, idVendor=2341, idProduct=0037
[22620.495263] usb 1-2: New USB device strings: Mfr=2, Product=1, SerialNumber=0
[22620.495268] usb 1-2: Product: Arduino Micro
[22620.495272] usb 1-2: Manufacturer: Arduino LLC
[22620.497393] cdc_acm 1-2:1.0: ttyACM0: USB ACM device
[22627.966141] usb 1-2: USB disconnect, device number 32
[22628.432089] usb 1-2: new full-speed USB device number 33 using ohci_hcd
[22628.572111] usb 1-2: device descriptor read/64, error -62
Anybody experienced this? I have tried to reconnect it multiple times to both computers, even tried a new cable doesn't help.
2 Answers 2
The USB part of the Atmega32U4 needs quite a bit of software to operate correctly, which is either not included in the basic blinky example or you got a binary for a different Arduino model.
The syslog looks like there is a bootloader present after Reset for a couple of seconds..
[22620.497393] cdc_acm 1-2:1.0: ttyACM0: USB ACM device
^
[22627.966141] usb 1-2: USB disconnect, device number 32
^
.. which shuts down and starts blinky. This is documented on the ArduinoBoardMicro page.
Re-flashing the chip is a bit tricky in this state, as you must press the reset button at the "right" time just before the software wants to access the chip.
If I push the reset button on it it comes back a bit then disappears again:
That's exactly how it works. The Micro enumerates as a Serial interface for a couple of seconds after reset, enough time for you to upload a new sketch. If you don't upload in time, and unless your code specifies a serial port, the serial interface goes away. Blink doesn't use a serial port.
You need to quickly press and release Reset at the exact moment that the IDE says it is uploading, and the board should then detect the new sketch.
The Leonardo and Micro differ from other Arduino boards in that they use a single microcontroller to both run your sketches and for USB communication with the computer.I don't see what else would you need to put into the basic blink example, if there is something board specific the compiler should put that in not you.the AVR chips can be programmed via spi and sometimes serial, which means not via usb- that's not correct. The Micro has a USB interface and is intended to be programmed by it.