DP83869EVM: Switch from 100BASE-FX to 1000BASE-X without rebooting the EVM?

Hi Alex,

Can you provide more details what you want to accomplish in your application?

Changing one operating mode to another requires at least a reset to the device.

Regards,

Hung Nguyen

Hi Hung,

Indeeed, some explainations about my application :

We would like make a one port 10/100/1000Mbps media converter from copper to SFP with, as possible, the possibylity to switch from 100BASE-FX to 1000BASE-X without reseting the product.

As I said in the first post, we dont know for the moment if we will need to place a PIC32 (or an ON-OFF contact) to change the operating mode of the media converter chip.

 

Operating Temperature : -40°C / +85°C

[RJ45 – Copper]               ↔         [Media converter chip]                               ↔         [Optical SFP]

10/100/1000Mbps                                                                                                       10/100/1000Mbps

 

Thanks for help.

BR

Alex

Hi Alex,

For your application, 10Mbps would not be possible with these modes. There is also a required register configuration for media converter modes. It would be useful to have PIC32 in your design. Please refer to this app note for more information about the media converter modes: www.ti.com/.../snla318.pdf

There is an alternative solution to your application if you're willing to use SGMII SFP module that supports both 100Base-FX and 1000Base-X. The DP83869 needs only be configured to SGMII-to-Copper mode

[RJ45-Copper] <-----> [MDI - DP83869HM - SGMII] <-----> [SGMII-100FX or SGMII-10000X SFP]

Regards,

Hung Nguyen

Hi Hung,

First, I said 10Mbps for SFP but it was a mistake...

You said 10Mbps is only available with configuration in register but if you take the app note (page 3 ; table 3),

ANEG_DIS = 0   /   ANEGSEL_0 = 0   /   ANEGSEL_1 = 0      -->   Auto Negociation (10/100/1000 Copper)

maybe you not told about the 10Mbps copper, right?

Yes, the goal is to use SGMII SFP module.

And, whats about the reset?

Thanks

BR

Alex

Hi Alex,

The required register configuration is for media converter modes as mentioned in the app note section 1.6 & 1.7. It has nothing to do with 10M speed as media converter modes do not support 10M.

If your application uses SGMII SFP module, the DP83869 can be configured to SGMII-to-Copper mode. There is no need to reset the device when switching between SGMII-100FX and SGMII-1000X. However, you need to make sure the speed on the copper side match the speed of the SGMII SFP module.

Regards,

Hung Nguyen