EB tresos Classic AUTOSAR：
Complex Device Driver (CDD) Technical Points
Focuses on explaining the interaction use cases between Complex Device Drivers (CDD) and the communication stack, basic development operations, and module implementation, helping developers efficiently build non-standard customized modules.
This article is based on the video content of 'High-Performance Expansion of Customized Functions using EB tresos Studio' provided by Elektrobit. The video introduces how to extend and customize functions in EB tresos Studio, focusing on explaining the interaction use cases between Complex Device Drivers (CDD) and the communication stack, basic development operations, and module implementation. It also demonstrates how to create custom code generators, helping developers efficiently build non-AUTOSAR standard customized modules, enhancing development automation and system integration capabilities.
1. What is a Complex Device Driver (CDD)?
A Complex Device Driver (CDD) is a special module within the AUTOSAR Basic Software (BSW). Although it belongs to the BSW layer, its design is highly flexible, allowing developers to bypass standard layering restrictions and directly access Microcontroller (MCU) hardware resources.
2. Why is CDD needed?
Although AUTOSAR promotes standardization, CDD is indispensable in the following three scenarios:
timer Extremely High Real-time Requirements
(High Timing Constraints): For example, high-frequency switching in fuel injection control or power electronics, where standard BSW stack processing latency might be too high, requiring direct hardware operation.
memory_alt Non-standard Hardware
Or Special Functions: When the hardware possesses special functions not defined by AUTOSAR standard modules (like MCAL).
history Integrate Legacy Code
(Legacy Code): If the company already has mature and verified non-AUTOSAR drivers, they can be quickly integrated into the new architecture through CDD encapsulation.
3. Interaction of CDD in the Architecture
The uniqueness of CDD lies in its ability to communicate across multiple layers simultaneously:
| Interaction Target | Communication Method | Purpose |
|---|---|---|
| Application Layer (SWC) | Through RTE | Provides processed complex data to the upper-layer logic. |
| Basic Software (BSW) | Direct API Call | Collaborates with other BSW modules (such as modular interfaces or diagnostic modules). |
| Hardware (MCU) | Direct Register Access | Achieve ultra-fast response or special hardware operations. |
4. Development and Configuration Recommendations
In EB tresos, developing a CDD typically involves:
-
code_blocks
Interface Definition: Define the Ports provided by the CDD in the tool to link with the RTE.
-
edit_square
Manual Implementation: Unlike standard BSW modules, most of the internal logic of a CDD needs to be manually written in C code by developers, as its functions are often highly customized.