DAP over CAN

A smart and simple way to access, flash and debug highly integrated ECUs during development.

Highly integrated ECUs are ECUs in EVs, especially high voltage ones. There are also other ECUs fairly difficult to access in the car without dismantling the hardware around (Dashboard, Roof Interieur, ...).

Instead of a cost-intensive scenario, ECUs hosting an Infineon AURIX controller offer access via the CAN bus physical layer. Two things have to be considered before using this possibility:

• DXCPL DAP over CAN Physical Layer Application Note from Infineon
• Use of an iSYSTEM DXCPL Converter

The iSYSTEM DXCPL Converter enables an iSYSTEM debug tool connection to the microcontroller via the regular CAN interface pins of the ECU. This connection is electrically robust due to the nature of the CAN bus. The DXCPL Converter translates Infineon AURIX™ SPD (Single Pin DAP) encoded DAP messages to the CAN bus physical layer.

Thus a "dead" or non-functional ECU can be revitalized by reflashing or debugging it (e.g., sporadic faults) via the CAN bus using the CAN connector of the ECU or an ECU very close to the ECU in question. The ODB interface (On-board Diagnostics) is not an option here. Flashing via ODB is a software function and impossible to access if an ECU is down. Debugging through this interface is not possible as well, because it is not a direct or very close connection running through several Gateways in addition.