May I have a question for Pre emphasis of DP83867IR
Question1. Does DP83867IR have the Pre emphasis function?
Is there register or automatic?
Question2. If there is setting register, please let us know this one.
BR,
Kosaka
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May I have a question for Pre emphasis of DP83867IR
Question1. Does DP83867IR have the Pre emphasis function?
Is there register or automatic?
Question2. If there is setting register, please let us know this one.
BR,
Kosaka
Hello Tadashi Kosaka
Thank you for the query.
Can you provide some background on the reason for asking this question.
Regard,
Sreenivasa
Hello Sreenivasa
We don't know DP83867IR has it or not. So we didn't set it.
Our LAN link is down at some system. So rerecheck around LAN function. But It is not clear depend on phy yet.
May I have answer for my question ASAP?
BR,
Kosaka
Hello Tadashi Kosaka
Thanks. The device does not support this function.
Our LAN link is down at some system. So rerecheck around LAN function.
Can you provide some additional details on the issues observed including the magnetics used and interface for review.
Regards,
Sreenivasa
Hellow Sreenivasa
I would like to know the chip spec at first. Trouble shooting is second.
Thers is register of Equalizer that is DSP_FFE_CFG( Address 0x012C).
It is only two mode over 1m or less than 1m.
Is my underastanding correct?
Is there another register?
BR,
Kosaka
Hello Tadashi Kosaka
Thank you for the reply.
Certain applications may need this register to be configured to 0x0E81 to improve Short Cable performance. Changing this register to 0x0E81, will not effect Long Cable performance.
Please note that it would help if you could explain the issues you are facing to provide better support.
Regards,
Sreenivasa
Hello Sreenivasa
This mean we can not control emphasis at DP83867IR over 1metre.
It is working automaticaly. Is my understanding correct?
Or Is theer other register?
Our system meet a receiver error and Idle Error at Phy so we investigage it.
BR,
Kosaka
Hello Tadashi Kosaka
Thank you for the reply.
If your system has performance issue for short cable, please use the register as below.
Certain applications may need this register to be configured to 0x0E81 to improve Short Cable performance. Changing this register to 0x0E81, will not effect Long Cable performance.
Regards,
Sreenivasa
Hello Streenivasa
I would like to reconfirm it.
DP83867IR does not have the emphasis register. Only one value for over 1metre.
Is my understanding correct?
And do you have some advice for a receiver error and Idle Error?
BR,
Kosaka
Hello Tadashi Kosaka
Thank you for the reply.
Please note that the register SP_FFE_CFG( Address 0x012C) we are discussing is for improving the short cable performance.
If you can provide some additional inputs on the test conditions when the error is occurring, we can review further. As a general input, you are right .
Regard,
Sreenivasa
Hello Streenivasa
Our system is using 75metre cable.
So our recognization is no need to change the settings from default.
What other information should we provide for a receiver error and Idle Error?
BR,
Kosaka
Hello Tadashi Kosaka
Thank you for the inputs.
You should not have any issue with 75M is all the recommended requirement for the PHY are taken care,
Now if we have to analyze the same we need to understand if this testing is being done on an EVM or custom board.
If it is a custom board, we need to understand the configuration, clock used, interface type, magnetics used, trace length etc.
Regards,
Sreenivasa
Hello Sreenivasa
Thank you for reply.
I would like to reconfirm. It shoud be working with default vale of SP_FFE_CFG( Address 0x012C) at 75m cable.
No need turn Equalizer(emphasis).
Is my undestanding correct? If yes, I will close this Item.
BR,
Kosaka