Introduction to AUTOSAR and its Effect on Automotive Software Architecture(part-3)
Published: 2023-12-11 16:38:14

Dear readers,
My name is Sadashiv Balawad and I am working as Junior Software Engineer at Luxoft India. Luxoft gave me many opportunities to work on various projects, which inspired me to talk about the importance of Autosar and its impact on automotive software development (Part 3).

**Layered Software Design for Multi-core Microcontroller**.
As the demand for computing energy intake is growing higher in the automobile domain, OEMs and Tier-one suppliers are progressively adapting using multicore ECUs of their digital architectures. Additionally, those multicore ECUs provide new features such as better stages of parallelism that enhance safety necessities implementation such as the purposeful protection widespread ISO26262 and the implementation of other greater complicated automobile packages, main uses of multi-core OS are as follows.

1. Decreasing complexity of architecture
2. Dealing with useful resource-demanding programs
3. Improving safety
4. Dedicated use of cores

AUTOSAR version four 4.0 has added assist for multi-core embedded RTOS. New standards inclusive of locatable entities (LEs), multi-core start-up/shutdown, Inter-OS-Application Communicator (IOC), introduced within the AUTOSAR four.Zero specification to increase the single-core OS specs. The Inter-OS-Application Communicator (IOC) that's a part of AUTOSAR OS, affords communication services that may be accessed with the aid of clients who need to talk across OS-Application barriers on the equal ECU. Every Core runs an ECU kingdom control and every middle additionally has a 'Core Test' module strolling in simple software program.
The improved Autosar structure would appear to be:

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/g8tp4dkr3wv4suwknev4.png)
      fig:Multi-Core Architecture of Autosar

At every level of software improvement compliance to AUTOSAR various gear are worried to ensure the interface is generated inline to conventional. A quick Autosar development drift is represented with the below go with the flow diagram. Even though this diagram does now not cover improvement flow applicable for all software program modules.

**Functional Safety:**
Safety of a device that depends at the anticipated operation of precise features. Functional safety wellknown ISO26262 is derived from IEC-61508 manual us to have an car-unique danger-based method for the development of Electrical and Electronic (E/E) systems. The goal of practical protection is to carry out the meant operation effectively or the gadget will fail and pass to a predictable safe country. Software is one of the parameters which can affect complexity at the device level. The new techniques and ideas for software program improvement can be used with the intention to minimize complexity and therefore can help to achieve practical protection. AUTOSAR R4.0 considers components of practical safety essential for Morden automotive software development.
There are many improvement techniques being followed under Autosar to detect and record the useful error at each level of software improvement. Even even though purposeful protection is relevant and followed at every stage of whole product development till it comes to the person.
Here is a listing of normal sources of interferences, causing mistakes detected by way of E2E safety:
SW-related sources:

S1. Error in in most cases generated RTE,

S2. Error in partly generated and partly manually coded COM

S3. Error in community stack

S4. Error in generated IOC or OS

HW-associated assets:

H1. Failure of HW community

H2. Network electromagnetic interference

H3. Microcontroller failure in the course of context switch or on the conversation between cores

An instance of a sensible approach followed while growing SWC’s interfaces is imparting End-to-End safety to facts correctness.
For each RTE Write or Read characteristic that transmits protection-associated records (like Rte_Write_<p>_<o>()), there's the corresponding E2E safety wrapper function.

1. The wrapper characteristic invokes AUTOSAR E2E Library.
2. The wrapper function is part of Software Component and is ideally generated.
3. The wrapper feature has the identical signature because the corresponding RTE feature, just instead of Rte_ there may be E2EPW_.
4. The E2EPW_ feature is known as through Application good judgment of SW-Cs, and the wrapper does the safety/tests and calls internally the RTE characteristic.
5. For inter-ECU conversation, the facts elements despatched via E2E Protection wrapper are via byte arrays. The byte arrays are copied to COM I-PDUs with none changes.

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/kzkppm4emzhsd6erw9ec.png)
       fig -E2E protection for safety compliance

**ECU Design and Configuration Methodology**
AUTOSAR affords a common technical approach for steps of machine development. The discern suggests a top level view of the design steps to build an ECU with AUTOSAR era.  That manner those steps should be carried out for each ECU in the system.

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/j50ubfxnuzhkw4jgysnk.png)
       fig- Autosar Configuration/Generation Workflow

To be mentioned AUTOSAR does no longer prescribe a specific order wherein development sports ought to be done..

The under diagram is an instance of a normally observed workflow. The above and below figure describe development glide for BSW and Application software program respectively.

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/2skkq32nc027ysvp3952.png)
             fig-Autosar Configuration/Generation Workflow


![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/7p2ajmjy4uwsbmyekb9e.png)

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/m664h2mv1a0iam67ns6e.png)

The main sports in this section are the extraction of ECU-unique data from the System Configuration Description, the configuration of the ECU, and the era of the executable ECU software program.  The following sections will describe these sports in more element.
This topic will be try to explain more in the next part

Thank you