Connecting DS125DF1610 with DS125DF410

Hi Wes,

Can you clarify what you mean by "connect two retimers together of the same type" and "communication from point A to point B through the two retimers die?" Perhaps a block diagram of the two test cases would be helpful here.

Where in the link is the data not passing through? For example, is the data getting past the DF410, locked, and not getting past the DF1610, or is it that nothing can lock?

Right off the bat, as long as you are supplying a signal that is operating at a data rate which the DS125DF1610 and DS125DF410 are configured to lock to (10.3125 Gbps and 1.25 Gbps by default), I do not see any particular quirks in the device that would cause these two devices not to work with one another. We have successfully implemented test cases in our lab where the DS125DF1610 drives a test signal through the DS125DF410 without any locking issue, so it would be helpful to understand your setup to track down the issue.

Regards,

Michael

Hi Michael,

I think we have found the source of the problem, need to confirm it with you:

I had a number of lanes inverted. Based on the datasheet, I was supposed to flip bit 7 of main,pre and post cursors of FIR filter, channel registers  1D 1E & 1F. bit 7 of post-cursor FIR_SEL_I_MAX was set by default and I kept it that way after flipping the sign bit. I found out that if I clear that bit, my signal inversion works fine. I couldn’t find any description of that specific bit.

My questions are

-        Does it really have to do something with inverting signals?

-        I still don’t understand why DS1610 tend to work with another DS1610 even before clearing FIR_SEL_I_MAX bit.

I will post the block diagram as soon as I have it.

Hi Wes,

The retimers should be polarity agnostic. Thus your result does not make full sense yet. We will need a block digram and more details on your retimer settings to be able to debug this.

Cordially,

Rodrigo Natal

DPS Applications Engineer, Retimers