LS1021A - 4-Lane 6GHz SerDes

[howardho]

There seems to be a discrepancy between the document TWR-LS1021A Reference Manual (Rev. 1 07/15) and the QorIQ LS1021A Data Sheet (Rev. 3 05/16) with regard to the SerDes usage. Figure 1. of the Data Sheet shows that only two Ethernet Controllers are associated with only 2 lanes the SerDes, whereas the Reference Manual shows all three Ethernet Controllers can be used with 3 lanes of the SerDes.

Please help clarify.

Thanks,

Howard

[ufedor]

> Shouldn't the following be 10/100/1000 Mbps?

You have a keen eye :smileyhappy:

Of course you're right again.

[howardho]

I am designing my own board, so I need to know the chip's capability wrt SGMII, not the board's feature. But, I think I know the answer now. Thx

Btw, Shouldn't the following be 10/100/1000 Mbps? (10/100/1G does not work either :-) ).

• Ethernet (from Board features)

— One onboard RGMII 10 G/100 G/1 G Ethernet port.

Thanks,

Howard

[howardho]

Take a look at "Figure 1-1. LS1021A block diagram" of the "TWR-LS1021A Reference Manual" document, and compare that to "Figure 1. LS1021A block diagram" of the "QorIQ LS1021A Data Sheet" document, you will understand what I mean.

Thanks,

Howard

[ufedor]

You are right.

Please consider that wording just before the figure is correct - i.e. 1.3 Board features:

• Ethernet

— One onboard RGMII 10 G/100 G/1 G Ethernet port

— IEEE 1588 test header on board

— Two onboard SGMII 10 G/100 G/1 G Ethernet ports

[ufedor]

> whereas the Reference Manual shows all three Ethernet Controllers can be used with 3 lanes of the SerDes.

What exactly do you mean?