UPGRADE YOUR BROWSER

We have detected your current browser version is not the latest one. Xilinx.com uses the latest web technologies to bring you the best online experience possible. Please upgrade to a Xilinx.com supported browser:Chrome, Firefox, Internet Explorer 11, Safari. Thank you!

cancel
Showing results for 
Search instead for 
Did you mean: 
Highlighted
Visitor ttzotzaros
Visitor
1,427 Views
Registered: ‎02-14-2018

100Gbps Ethernet PHY and GT transceiver wizard

Jump to solution

Hello!

 

I am designing the PHY layer for 100GBASE-R Ethernet application. I am working Virtex Ultrascale xcvu125-flvb2104-2-e, some QSFP+ modules and the Vivado 2017.4. I am using GT transceivers wizard in order to instantiate a core. Because I have never implement something similar before in this hardware and software, I have some questions:

 

a)

If I choose a GTY_CAUI_4 preset from the wizard, I get a core which  has two ports: gtwiz_userdata_tx_in(319:0) and gtwiz_userdata_rx_in(319:0) and has no inputs or outputs for headers. The gearbox is missing (why???).

 

For what reason are these two ports? Are these the 10 parallel lanes of a PMA? Or they are just 4 interfaces of 80 bits to serdes? I assume that I must design the PCS in my own. Right?

 

By the way, the 320 bits are not divisible with 66. So I have to convert 66 bits to 64?

 

b) If I choose a line rate of 25,87125G, four channels and a synchronous or asynchronous gearbox with CAUI mode, I get some errors about unsupported speed grade. What I am doing wrong? If I select normal mode, then the wizard does not complain.

 

Can you help me please?

 

 

 

 

0 Kudos
1 Solution

Accepted Solutions
Explorer
Explorer
2,041 Views
Registered: ‎03-31-2016

Re: 100Gbps Ethernet PHY and GT transceiver wizard

Jump to solution

On part a) that preset is intended for use with the 100G PCS/MAC hard IP which does all the gearbox internally so it defaults to the 80bit per SERDES raw mode (no gearbox).

 

On part b) CAUI mode is intended for CAUI-10 10.3125G SERDES,  The 20 Virtual lanes of all CAUIs map well to 2:1 logic used in "CAUI Mode" and 10 Physical lanes.

 

For CAUI-4 you could do use the non "CAUI Mode" of the 64/66 gearboxes and do the 4 Physical to 20 Virtual lane mapping in your own logic.

4 Replies
Explorer
Explorer
2,042 Views
Registered: ‎03-31-2016

Re: 100Gbps Ethernet PHY and GT transceiver wizard

Jump to solution

On part a) that preset is intended for use with the 100G PCS/MAC hard IP which does all the gearbox internally so it defaults to the 80bit per SERDES raw mode (no gearbox).

 

On part b) CAUI mode is intended for CAUI-10 10.3125G SERDES,  The 20 Virtual lanes of all CAUIs map well to 2:1 logic used in "CAUI Mode" and 10 Physical lanes.

 

For CAUI-4 you could do use the non "CAUI Mode" of the 64/66 gearboxes and do the 4 Physical to 20 Virtual lane mapping in your own logic.

Visitor ttzotzaros
Visitor
1,334 Views
Registered: ‎02-14-2018

Re: 100Gbps Ethernet PHY and GT transceiver wizard

Jump to solution

Thanks for your reply

 

I begin to understand the GTY interface

 

0 Kudos
Adventurer
Adventurer
1,300 Views
Registered: ‎02-06-2018

Re: 100Gbps Ethernet PHY and GT transceiver wizard

Jump to solution
@ttzotzaros did you use 100G Ethernet IP Core subsystem?
0 Kudos
Visitor ttzotzaros
Visitor
1,279 Views
Registered: ‎02-14-2018

Re: 100Gbps Ethernet PHY and GT transceiver wizard

Jump to solution

No.

 

I want the PHY only. I think that the MAC implementation can not be removed from the design

0 Kudos