I/O signal to port mapping for XS1-L1-48pin USB Audio RD

[eladmmor]

Dear Xmosers!
I am currently impementing a version of the USB Audio reference design that is using the 48-pin package instead of the 128-pin.
I am having some trouble to make sure that the I/O signal to port mapping is correct;
Following [1], I've used the X0D0, X0D1, X0D10, X0D11 for the SPI interface.
Following [2], I have matched the entire ULPI signals group.
Thats leaving me with exactly four signals [3]: XCORE_MCLK, PHY_RST_N, MCLK_SEL, SPDIF_TX
which I have connected with ports(respectively): X0D52, X0D53, X0D54, X0D55.
I did that in order to use the same port - 32A. Is that a valid connection?

Thanks!!

https://www.xmos.com/download/public/XS ... 38E%29.pdf - [1]page 4 , [2]page 17

[3] https://www.xmos.com/download/public/US ... 1.0%29.pdf - page 13

[eladmmor]

Let me try to rephrase the question:
By choosing the above four signals (XCORE_MCLK, PHY_RST_N, MCLK_SEL, SPDIF_TX) to be assigned with port 32A - can I access each of them seperately?

[Bianco]

Let me try to rephrase the question:
By choosing the above four signals (XCORE_MCLK, PHY_RST_N, MCLK_SEL, SPDIF_TX) to be assigned with port 32A - can I access each of them seperately?

That sounds like a bad idea. You have a mixture of input and output pins while the port can be only in one direction at a time. To make things worse the XCORE_MCLK and SPDIF_TX have to be on 1-bit ports.

[eladmmor]

Thanks for your helpful comment!
I've changed the assignment to 24,25,34,35 which are all 1-bit ports.

[Bianco]

You might want to check in the reference software how certain pins/ports are used to maintain compatibility with the reference software

[eladmmor]

Thats exactly what I'm looking into now.. thanks again.

[Ross]

Apart from moving around some of the pins on the 32bit port you should not have to change any other io mapping when moving from 128pin to 48pin for the USB audio reference design.