What are the consequences of ports (not pins) being used by USB?

If you have a simple question and just want an answer.
Posts: 1
Joined: Thu Feb 07, 2019 10:12 pm

What are the consequences of ports (not pins) being used by USB?

Postby ulikoehler » Thu Feb 07, 2019 10:46 pm

When using USB on, for example, the XEF216-512-TQ128 (on Tile 0), Figure 11 (page 18) in the datasheet shows that some ports like 1K, 1H, 8B, ... are used by USB.

Let's take port 1K as an example. Pin X0D34's only function (besides a XLink pin) is 1K.

Does that mean that when (actively) using the USB PHY (on Tile 0), I can't use Pin X0D34 since it's connected to Port 1K and Port 1K is already used by USB?

What about pins with multiple ports like X0D14 (Port 8B is used by USB). Does using the USB mean I can't use that pin even if I want to use it as 4C0?

My application is to create a "generic" Base board for different types of daughter boards (mainly high-speed ADCs and DACs, or ADCs and DACs with a lot of channels). This means that I need to have as many pins available as possible to connect to the daughter boards. Since I want to be able to use RGMII and USB (not neccessarily both at once), not being able to use pins like X0D14 or X0D34 would mean that I have very few pins available to connect to the daughter boards.

I am aware of the "xCORE-200 Devices Portmap", but that just shows me which ports are used by USB, but is unclear about whether the pins will still be available if the ports are used.

My understanding is that e.g. if Port 8B is used by USB, the port is not any more connected to the USB, so I can use X0D14 (just not as 8B0), but I can o nly use X0D34 as an XLink pin.

Thanks & best regards,

Who is online

Users browsing this forum: No registered users and 1 guest