OLIMEX© 2015
A20-OLinuXino-MICRO user's manual
There are two parts of a successful OTG device/host mode switch and usage – hardware part and
software part.
The hardware part is the cable – to use the OTG as a host you would need a mini USB to USB
adapter cable. Do not confuse micro and mini USB!
The software part is loading a kernel module responsible for the behavior of the board while in
device mode. If such software is not enabled or missing in the official distribution – you would
need, respectively, either to load the module or rebuild the kernel to enable the module. There are
several modules that you might need depending on what your goals are.
USB_OTG connector
Pin #
Signal name
Processor pin
1
+5V_OTG_PWR
-
2
UDM0
N20
3
UDP0
N21
4
USB0-IDDET
B5
5
GND
-
The connector case is also grounded.
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