Readback of communication data between EMAC and PHY

Arriy

I am reading "Safety Manual for TMS570LS31x and TMS570LS21 x Hercules ARMR-Based Safety Critical Microcontrollers (Literature Number: SPNU511D)" and

"TMS570LS31x/21x 16/32-Bit RISC Flash Microcontroller Technical Reference Manual(Literature Number: SPNU499B)".

Described as " If the EMAC module fails to read back the values that it is attempting to write to the physical layer (PHY),the hardware will indicate a Physical Layer Fault. Error response and any necessary software requirements are defined by the system integrator" in chapter "7.30 Ethernet Physical Layer Fault " of Safety Manual.

How do I do readback of communication data between EMAC and PHY ?

I think by SW processing, comparison of transmit data MII_TXD[3−0] from EMAC and receive data MII_RXD[3−0].

And, MII_TXD[3−0] and MII_RXD[3−0] are the same ?

over 8 years ago

0 Charles Tsai over 8 years ago

TI__Guru**** 191886 points

Hi Arriy,

Communication between the EMAC and the external PHY is carried out via the MDIO interface. Please refer to the 29.2.8 MDIO Module for details. The MDIO interface consists of two signals, the MDIO_CLK and MDIO_D. This is a separate interface from the MII interface consisting of the MII_TXD/MIIRXD. In section 29.2.8.2.2 you will find instructions on writing data to a PHY register and reading data from a PHY register.

0 Charles Tsai over 8 years ago in reply to Charles Tsai

TI__Guru**** 191886 points

Hello Arriy,
Is your question answered? If your question is answered can you please click the 'Verify Answer' button to close the thread? Thanks.

0 Arriy over 8 years ago in reply to Charles Tsai

Expert 1720 points

Hi Charles,

Realization of "If the EMAC module fails to read back the values that it is attempting to write to the physical layer (PHY),the hardware will indicate a Physical Layer Fault." is possible with MDIO_D readback ?

0 Charles Tsai over 8 years ago in reply to Arriy

TI__Guru**** 191886 points

Hi Arriy,

Please see below description in the MDIO CONTROL register.

0 Arriy over 8 years ago in reply to Charles Tsai

Expert 1720 points

Hi Charles,
Thank you your answered.
I can understood.

0 Arriy over 8 years ago in reply to Arriy

Expert 1720 points

Hi Charles,
I have a new question.

After the readback error occurs, the message by the Ethernet is retransmitted ?
Also,this processing is automatically ?

0 Arriy over 8 years ago in reply to Arriy

Expert 1720 points

I want to answer this question.
Please answer.

0 Anthony F. Seely over 8 years ago in reply to Arriy

TI__Guru 68930 points

No there is not any automatic retransmission done by hardware.

You need to treat the Ethernet IP as a black channel communication device.
Meaning that you need to make sure the protocol you are using, and your application software, take the appropriate measures for your SIL level. There's nothing in the hardware that you can rely on.

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Readback of communication data between EMAC and PHY