ISO 20794-4:2020

This document specifies the CXPI data link layer and the CXPI physical layer.
The DLL is based on:
-  priority-based CXPI network access;
-  non-destructive content-based arbitration;
-   broadcast frame transfer and acceptance filtering; and
-   node related error detection and error signalling.
The CXPI physical layer (PHY) requirements comprise of:
-   physical signalling (PS) sub-layer, which specifies the requirements of the clock generation function, the encoding and decoding of CXPI frames, and bit-wise collision resolution logic;
-   physical media attachment (PMA) sub-layer, which specifies the requirements of the signal shaping waveform logic;
-  physical media dependent (PMD) sub-layer, which specifies the requirements of the CXPI network termination, electrostatic discharge protection, etc., and device connector requirements; and
-   physical media (PM), which specifies the requirements of the CXPI network cable/wiring harness.