TJA1120 for Timesync

[xuliming2]

Hello everyone,

I have questions about 1000BASE-T1 PHY TJA1120 which support IEEE1588v2 and 802.1AS-rev 2-step timestamping.

Q1: Could TJA1120 implement the IEEE1588 timesync in hardware? Or the PTP server should also be run in software? I think if the TJA1120 support IEEE1588 protocol, the software PTP server is not necessary, the two TJA1120 could finish timesync themselves.

Q2: Does TJA1120 support to output a Pulse-Per-Second (PPS) signal for triggerring functions.

Thanks and Regards

[PavelL]

Hello @xuliming2 ,

I apologize for the late response. I've been checking answers with application engineer.

A1: The TJA1120 supports IEEE1588. The PTP module is sandwiched between the MII/GMII interface. The module provides a 1588 digital clock implementation, transmit and receive frame parsing, Start-of-Frame detection, transmit and receive timestamp units, event timestamp unit and a Pulse-Per-Second (PPS) generator. The (g)PTP Server should run in software (MAC). Please check the TJA112x Application Note.

A2: Yes, it's called PPS_OUT. Please refer to TJA1120 Data Sheet.

BTW, new version of TJA1120's application note and data sheet have been released recently.

Best regards,

Pavel