NEXT GENERATION VEHICLE DIAGNOSTIC SYSTEMS

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1 Volume 116 No , ISSN: (printed version); ISSN: (on-line version) url: doi: /ijpam.v116i11.26 ijpam.eu NEXT GENERATION VEHICLE DIAGNOSTIC SYSTEMS V.Vanitha 1, V.P.Sumathi 2, J.Cynthia 3 and B.Illakia 4 Kumaraguru College of Technology, Coimbatore-49, Tamilnadu, India. vanitha.v.cse@kct.ac.in, sumathi.vp.cse@kct.ac.in,cynthia.j.it@kct.ac.in, ilakkiyaboopathy@gmail.com Abstract Engine Control Unit (ECU) plays a vital role in an automobile industry which allows the automobiles to be more fuel efficient and to provide optimal performance. It is the core part of vehicle engine and consists of microprocessor, peripheral hardware and control software. It ensures the proper functioning of a vehicle. A large number of micro controller chips are embedded inside the ECU and ensuring accurate functioning of these chips is essential, because proper functioning of these chips ensures the proper functioning of vehicle. The proposed work deals with ensuring the proper functioning of ECU. It makes use of Robert Bosch s CarPU Flash Interface (CFI) tool to test thirteen different micro controller chips embedded inside the ECU. CFI tool enables initialization, programming and testing of ECU. Proposed work involves ensuring whether the chip performs its assigned functionality accurately. To accomplish this Application Specific Integrated Circuit (ASIC) description file and test step algorithm are generated for individual chips based on the information provided in the data sheet. These data are inserted into XML file and this XML file is used to generate interface to read inputs from the user. The input provided by user is converted to low level form and transmitted to the CFI tool to check the chip functionality. 251

2 Keywords: Engine Control Unit, Controller Area Network, CarPU Flash Interface. I. Introduction In automobiles an Electronic Control Unit (ECU) is an embedded electronic device, basically a digital computer that read signals coming from sensors placed at various parts and in different components of the vehicle [1]. This information controls various important units (e.g. engine) and automated operations within the car. It also keeps a check on the performance of some key components used in the car. An electronic control unit contains the hardware and software [8]. The hardware consists of electronic components on a Printed Circuit Board (PCB), ceramic substrate or a thin laminate substrate. The main component on this PCB is a microcontroller chip. The software is stored in the microcontroller or in other chips on the PCB, typically in EPROMs or flash memory. So the CPU can be reprogrammed by uploading updated code or replacing chips. 2 ECU Interface Design The functional block diagram of proposed method is shown in the Figure 1.The components are PC, CarPU Flash Interface tool and Engine Control Unit. The communication between device and CFI is established using Universal Serial Bus (USB) and the communication between CFI and ECU is established using Controller Area Network (CAN) bus. 252

3 Figure 1 ECU interface design Engine Control Unit consists of many micro controller chips (such as SMP480, digital pin etc.,) of number of pins and ports and they are programmed to perform the functionality specified by the car manufacturers. Each chip has its own data sheet that provides information about chip functionality and, port and pin number in which chip accepts input and provides output. 2.1 Generating XML Schema Definition XML Schema Definition is generated for Application Specific Integrated Circuit and it provides information about the following [6]. The sample XSD for ASIC is given in Figure 3. IO signals: It provides information about type of input and output signals used and it can be either Serial Peripheral Interface or Micro Second Channel. Register groups: It contains name, category of the registers (read registers, write registers) and description of the category. Power stage details: It provides information about static and PWM power stages. 2.2 Generating ASIC description file and Test Step Algorithm ASIC file for individual chip must be defined as per ASIC XSD. Some important tags and attributes are described with their usages in the Table The ASIC description file and test step algorithms for the chip CJ950 is given figure 2 and figure 3 respectively. Input and output signals The signals are FCLP, FCLN, EN, SOP, SON and SDI which are the MSC signals. These signals with their type, direction and descriptions are 253

4 mentioned under the SIGNALS. Read Registers The read registers like Diagnostic registers, Identity registers and Configuration registers and out registers are identified. These registers, with their command instruction value, length and their command response are mentioned under the tag REGISTERS. Each register type is separated as register groups. Write Registers The write registers are identified. Each bit / byte in the command instruction of the register, for which the user needs to enter the value, is noted. Static and PWM Power stages Static power stages The Static power stages have two important parts STATES and PINS. The STATES will say the various states of the power stage and their value either bitwise or byte wise. The PINS section will have OUT pins with their mask values, length and description. PWM power stages The PWM power stage does not have the STATES section and only have the PINS section. The PINS section will have OUT pins with their mask values, length and description, as in the static ones. Figure 2: ASIC description file for chip CJ Load the required HAL file. Here, IFX device 3 is used 2. Load the required TSW files. 3. As per the communication buses available in CJ950, MSC will be used. 4. The input signals are FCLP, FCLN, EN, SOP, SON and output signals are SDI. 5. Set the MSP ports and pins 6. Then set pin signal properties using TSW-04, command Then to initialise the MSC ports for specific controllers, call TSW-03, command Then to configure MSC frame as DATA LOW and then as COMMAND, use TSW-03, command-02 with the respective parameter values. 9. Add POWERSTAGES and REGISTERS. 254

5 Figure 3: Test Step Algorithm of CJ950 Conversion of XML to Java dialogues and Data Transmission XML files created are used to generate dialogues that allows user to select parameters required by the chip. Interface generated mainly contains type of input and output signals, name of the read and write registers, PWM and static power stages, ports and pin numbers through which the chip accepts input and writes output and it allows the user to select the value for these parameters. The value for these parameters will be in high level language which cannot be transmitted to ECU. So they are converted to low level language (hexadecimal values) and then they are transmitted to ECU using Controller Area Network bus [7]. 3. Experimental Results The proposed work is implemented in java using net beans IDE. The user selects the chip to be tested from the drop down list that is displayed in a graphical tool. The parameters needed to test the chip are given in a dialogue that gets displayed as a result of selecting the chip. The parameters are selected and loaded in CFI table. These parameters are in high level language, so they must be converted to a form that can be understandable by a chip, then they are transmitted to the corresponding chip inside ECU using Bosch s CFI tool. The main complexity involved in manual testing of chip is, in order to ensure the functionality of the chip, the user should specify the parameters of the chip in low level language. CFI tool helps the user to reduce the complexity involved in manual testing of the chip, because it provides interface through which parameters are given in high level language and they are converted to low level language, then they are transmitted to ECU. 255

6 3.1 SMP480 Data required for testing the chip are extracted from the datasheet of chip SMP480 and ASIC XML file is generated. This XML file contains information about port, pin number, read registers and write registers used to generate an interface through which the data is read from the user. The data that is in a high level language are then converted to low level language and they are used to communicate with the chip SMP480 in ECU. Figure 4 shows the interface through which the user provides the required input. Figure 4 Interface for reading the input. Generation of hexadecimal values Hexadecimal values are generated using the hexadecimal equivalent given for parameters of the chip in ASIC XML and Test Step Algorithm XML. These values are transmitted to ECU using CFI tool. Figure 8 shows the SMP480 hexadecimal value generation. Figure 5 SMP480 hexadecimal value generation. 3.2 CJ

7 CJ950 interface allows the user to set and initialize. Micro Second Channel type signals set the value for power stages and to specify read and write registers. Figure 6 shows the interface generation for ASIC CJ Conclusion Figure 6 Interface generation for ASIC CJ950 ECU is considered as the heart of an automobile and it is essential to confirm whether the ECU performs its functions accurately. The Bosch s CFI tool is used to test these micro controller chips and it has been carried out by reading the parameters of the chip from the user. This work developed a user interface using which the user enter input to test the chips in the ECU. These data are then converted into hexadecimal form and transmitted to the chip with the help of CFI tool and it is tested to ensure its functionality which helps the vehicle to deliver ideal performance. References 1. Boss, B. (2012, June). Architectural aspects of software sharing and standardization: AUTOSAR for automotive domain. In Proceedings of the Second International Workshop on Software Engineering for Embedded Systems (pp. 9-15). IEEE Press. 2. Rueger, J. J., Wernet, A., Kececi, H. F., & Thiel, T. (2013). MDG1: The new, scalable, and powerful ECU platform from Bosch. 257

8 In Proceedings of the FISITA 2012 World Automotive Congress (pp ). Springer Berlin Heidelberg. 3. Kong, F., Zhang, L., Zeng, J., & Zhang, Y. (2007, August). Automatic Measurement and Control System for Vehicle ECU Based on CAN Bus. In 2007 IEEE International Conference on Automation and Logistics (pp ). IEEE 4. Hui, D., Bo, H., Dafang, W., & Guifan, Z. (2011, March). The ECU control of diesel engine based on CAN. In Intelligent Computation Technology and Automation (ICICTA), 2011 International Conference on (Vol. 1, pp ). IEEE. 5. Sandmann, G., & Thompson, R. (2008). Development of AUTOSAR software components within model-based design (No ). SAE Technical Paper. 6. Weichel, B., & Herrmann, M. (2004). A backbone in automotive software development based on XML and ASAM/MSR (No ). SAE Technical Paper. 7. Davis, R. I., Burns, A., Bril, R. J., & Lukkien, J. J. (2007). Controller Area Network (CAN) schedulability analysis: Refuted, revisited and revised. Real-Time Systems, 35(3), Ilakkiya B, Vanitha V. (2016). A Survey on Engine Control Unit, IJARIIE, Vol-2 Issue-3,

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