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Originally Posted by afarre
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Sorry about my english, but I do not undestand what you mean.
Do you mean USBH-N could be "here" (see picture)?
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No. These types of circuit boards use blind vias. A via is essentially a feedthrough from one layer to another. With the older 2-sided PCBs, they were simple feedthroughs from the top to the bottom.
However, that changed on todays multi-layer PCBs. If the Axim uses a 6 or 8 layer board, you will have the top and bottom layers plus a 5v and gnd layer. You will also have the conductor layers which will be in-between the other layers. In order to get connections from one internal layer to another, vias are used. They become blind vias when they are only in the inner layers and don't appear on the top or bottom of the PCB.
If you look really close at the top of the X50/X51 PCB, you will see what look like small pads just under the top surface. Those are on the 2nd layer of the board and you cannot connect to them.
Unfortunately, since I don't think the USBH-N pad is on the bottom, you cannot just scrape away some copper and expect the blind via to be there (but it would be nice though).
What I meant in my previous post was that I would scrape off the green soldermask from a number of vias that are exposed on the bottom of the PCB and see if any are connected to USBH-N (you never know).
I hope this explains things more clearly.