cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 
Highlighted
Adventurer
Adventurer
1,607 Views
Registered: ‎07-02-2014

GMII to MII & MII to GMII conversion

Jump to solution

Hi all,

I am trying to Interface Custom MAC with SGMII up core, 

Custom MAC for 1000 Mbps -> GMII interface -> 8 bifs-> 125 MHz. 

                         For 100. Mbps -> MII interface -> 4 bits -> 25 MHz  (upper 4 bits are not used)

                         For 10 .  Mbps -> MII interface -> 4 bits -> 2.5 MHz 

 

But SGMII ip up core gives 8 bits for 10/100/1000 Mbps at 1.25,12.5 and 125 MHz respectively

So now we have to convert on Rx side (sgmii IP core to Mac) 

 8 bit interface at 12.5 MHz to 4 bit interface at 25 MHz  for 100 Mbps

8 Hit interface at 1.25 MHz to 4 bit interface at 2.5 MHz for 10 Mbps

And for 1000 Mbps it should be as it  is passed 

 

On TX side we have to convert ( MAC TO SGMII CORE)

4 bit interface at 25 MHz to 8 bit interface at 12.5 MHz

4 bit interface at 1.25 MHz to 8 bit interface at 2.5 MHz

And for 1000 Mbps it should be directly passed 

 

Any suggestions please how to proceed on this ??

 

Thanks...

 

0 Kudos
1 Solution

Accepted Solutions
Highlighted
Adventurer
Adventurer
1,484 Views
Registered: ‎07-02-2014

We have written custom wrapper as present in the sgmii ip core when we choose Zynq as the target  board with minor changes in our design with VCU118 kit. with that it worked at all the three speeds. 

 

 

Thanks

 

View solution in original post

sgmii_ip.PNG
0 Kudos
2 Replies
Highlighted
Moderator
Moderator
1,548 Views
Registered: ‎08-25-2009

Hi @mdakram140,

 

As you understand correctly, our SGMII will run at 125Mhz, 12.5MHz, and 1.25MHz and repeating the data for lower speed - 10/100 times. It has a GMII block which is interfaced to MAC using GMII.

 

With your custom MAC, I am not sure how you can use SGMII IP out of box without hacking it. And it won't be that simple. Any chance for you to consider using our MAC instead?

"Don't forget to reply, kudo and accept as solution."
0 Kudos
Highlighted
Adventurer
Adventurer
1,485 Views
Registered: ‎07-02-2014

We have written custom wrapper as present in the sgmii ip core when we choose Zynq as the target  board with minor changes in our design with VCU118 kit. with that it worked at all the three speeds. 

 

 

Thanks

 

View solution in original post

sgmii_ip.PNG
0 Kudos