Olimex Support Forum

OLinuXino Android / Linux boards and System On Modules => A13 => Topic started by: bruceuk on December 10, 2014, 02:33:45 PM

Title: A13-SOM: Attach USB device
Post by: bruceuk on December 10, 2014, 02:33:45 PM
Hi

I wanted to ask if anybody could give me some tips on attaching a USB device to my A13-SOM.

I use the A20-SOM for initial dev work (easy nfs boot etc) and then migrate over to the A13-SOM. First issue is I can't find the USB pins when looking at the schematic, so far I've searched:

http://free-electrons.com/~maxime/pub/datasheet/A13%20user%20manual%20v1.2%2020130108.pdf
https://www.olimex.com/Products/SOM/A13/A13-SOM-512/resources/A13-SOM512_sch.pdf

Looking at the Olimex PNG, I can see:
processor pin 97 V3 _USB       : unknown
processor pin 15  USB0-DRV     : GPIO3 pin 6
processor pin 153 USB0-IDDET   : GPIO3 pin 4
processor pin 154 USB0-VBUSDET : GPIO3 pin 2

How does the above map to USB [ +  D+  D-  - ]

Which pins on the A13-SOM headers should I attach my usb?

As always, any help would be much appreciated!

Thanks
Bruce


Title: Re: A13-SOM: Attach USB device
Post by: Gerrit on December 10, 2014, 03:25:44 PM
USB-HOST
processor pin 96 UDP1 D+ GPIO-2 pin 5
processor pin 95 UDM1 D- GPIO-2 pin 7

USB-OTG
processor pin 94 UDP0 D+ GPIO-2 pin 1
processor pin 93 UDM0 D- GPIO-2 pin 3


Look at the A13 (not SOM) schematic for more info
https://github.com/OLIMEX/OLINUXINO/blob/master/HARDWARE/A13-OLinuXino/A13-OLinuXino_WIFI_Rev_E.sch.pdf
Title: Re: A13-SOM: Attach USB device
Post by: bruceuk on December 10, 2014, 03:36:27 PM

Hi Gerrit

Excellent, thank you!!

What are you doing for the USB 5V + and - ?

Thanks
Bruce

Title: Re: A13-SOM: Attach USB device
Post by: JohnS on December 10, 2014, 03:53:45 PM
The chip data sheets etc are also worth close attention.  Usually I find the newest are on linux-sunxi.org

John
Title: Re: A13-SOM: Attach USB device
Post by: Gerrit on December 10, 2014, 04:55:32 PM
Quote from: bruceuk on December 10, 2014, 03:36:27 PM
What are you doing for the USB 5V + and - ?

Any decent 5 Volt 500mA - 1A  power supply will do, connect the - also with the ground of the board
Title: Re: A13-SOM: Attach USB device
Post by: bruceuk on December 10, 2014, 05:07:19 PM

Got it, thanks!! 

Actually realized it was a bit of a stupid question :)

Picked up one of these bad boys so will have a go this evening:
http://www.auseparts.com.au/image/cache/data/Arduino/Accessories/MB102%20Breadboard%20Power%20Supply%20Module%203.3V_5V%20BB-500x500.png


Bruce