DP83848Q-Q1: LED_LINK active between DP83848Q - 83849I

Hello Kai,

Is there any difference between mode configuration of 849 and 848 under use? Is auto-negotiation active for only 848?

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Regards,

Vikram

Hi Vikram,

both are default register setting.

Regards,
Kai

Hi Vikram,

848Q1 doesn't have AN_EN hardware strap so we have to change BMSR 0x00h/ bit12 to "0" when Auto-negotiation is disabled.

Regarding 848Q1 auto-negotiation,
- what is the default value of bit12? 1/enable or 0/disable?
- is it ok to think that all of default value is "1"?
- are there any way to disable AN_EN with hardware strap?

Regards,
Kai

Hi Vikram,

this is kindly reminder.

Regeards,

Kai

Hi Kai,

Sorry I did not get your question. I see the strap options for aneg enable/disable in the datasheet. Are we looking at different datasheets :

https://www.ti.com/product/DP83848-EP#:~:text=DP83848%2DEP%20ACTIVE&text=The%20DP83848%2DEP%20was%20designed,defense%20and%20industrial%20control%20applications.

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Regards,

Vikram

Hi Vikram,

Phy is not EP but Q1.

848Q1 datasheet said default Auto-negotiation Enable is Strap but there is no AN_EN strap setting in 848Q1 datasheet although non Q1 version has AN_EN strap setting.

Actually there are three questions so could you help?

Regarding 848Q1 auto-negotiation,
- what is the default value of bit12? 1/enable or 0/disable?
- is it ok to think that all of default value is "1"?
- How to disable AN_EN with hardware strap?

Regards,

Kai

Hi Kai,

Thanks for clarification. Now looking at 848Q1 datasheet I can answer the following (but I am double checking with team here and will get back to you) :

1. bit 12 = 1 by default and we need to make it 0 to disable auto-negotiation.

2. Yes 1 is the default value.

3. No hardware strap option availablie in Q1.

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Regards,

Vikram