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USB-2-MDIO: MDIO clause 45, extended register access issue

Part Number: USB-2-MDIO
Other Parts Discussed in Thread: MSP-EXP430G2ET

Hello, 

I want to use USB-2-MDIO GUI with MSP-EXP430G2ET launchpad to access registers of a PHY. This PHY is not from Texas instrument. 

This PHY (marvell 88x5113) has MDIO/MDC access to his registers using indirect access specified by IEEE Clause 45.

please find below explanation from Marvell datasheet:

 

I should provide the PHY address, Device address and register address. But on the GUI there is nowhere to provide the device address

My question is : 

- is it possible to access to the extended registers using the GUI USB-2-MDIO ??  i know there is a field to choose extended register but my main concern is that I should provide device address. 

- if not, is there a way to use commands or script to do it ?  

This topic has be discussed here, but this was regarding a TI PHY, which is not my case. 

https://e2e.ti.com/support/interface-group/interface/f/interface-forum/1262102/usb-2-mdio-gui-support-for-changing-device-address-field-tlk10034?tisearch=e2e-sitesearch&keymatch=usb%25202%2520mdio%2520device%2520name%2520msp430flasher#

https://e2e.ti.com/support/interface-group/interface/f/interface-forum/1271487/faq-extended-register-space-access-for-ethernet-phys?tisearch=e2e-sitesearch&keymatch=usb%2525252525202%252525252520mdio%252525252520device%252525252520adress%252525252520extended%252525252520register#

Please if you have any idea or material this would be helpful

Thank you !

NOTE: i had an idea:

Let say i want to read register 0xF845,    PHY address=b00000  (0x00)      , DEVICE address=b11111   (0x1f)

STEP 1:

I should access with not extended register , the mdio clause 22 described below

so in order to read the register I would:

1/ write to register 0x1f (my device address) value 0xF845 (my register address)

2/read register 0x1F

a read is op=10 and write op=01  instead of  the fist write I should use operation =00 that sets the address but unfortunately I don't have this choice using the GUI

STEP 2: 

I had the idea maybe I should send direct serial commands to the MSP-EXP430G2ET without interfacing with the GUI. With this manner I should find the correct serial command to send to the MSP-EXP430G2ET where the MSP-EXP430G2ET will be able to translate it to the wanted MDIO frame. (and set operation bits b00)

I first spied the serial command send by USB-2-MDIO, it looks like that: 

read extended register PHY 00, register f845  -->      00f845*/

read not extended register PHY 00, register f845  -->    00f845=/

write extended register PHY 00, register f845, value 0xa4 -->     00f84500a4*/

Unfortunately the serials commands are basics, it's still high level approach so is seems there is no way to control the exact MDIO command.

  • Hello,

    PHY ID is the same field as PHY address. As USB2MDIO was made with TI PHYs specifically in mind, please select "No" for extended register as this will conduct extended register access via D-E-D-E method as described in TI PHY datasheet for indirect access.

    Sincerely,

    Gerome

  • Hello Gerome, thank you for your answer ! 

    Ok I should not use extended register functionality.

    Now my issue when using classic mdio is that with the GUI I can only choose to read or write. read is translated as operation code 10 and write as 01. But I would like also to use operation code 00 for sending first the address (please look at the table from first message, this is mdio clause 45). I guess there is no way to control this, unless to update MSP430 firmware... I guess I need to find an other way to send my mdio commands. 

    Just in case, would it be possible to get the MSP430 firmware source code for USB2MDIO or is this one proprietary to TI? I only get the binary to flash it.

    thank you, 

    regards, 

    Hanna

  • Hi Hanna,

    Unfortunately, this code is proprietary to TI.

    Sincerely,

    Gerome

  • ok, thank you anyway :)