EH2144A Datasheet V1.2 EH2144A. Vehicle Control Unit for Electric & Hybrid Vehicles. Datasheet V1.2. Copyright ECOTRONS LLC. All Rights Reserved

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1 EH2144A Vehicle Control Unit for Electric & Hybrid Vehicles Datasheet V1.2 Copyright ECOTRONS LLC All Rights Reserved

2 Revision History Date Revision Description Aug V 1.1 First release Sep.2017 V 1.2 Contact US: Web: info@ecotrons.com Copyright ECOTRONS LLC Page 2

3 Table of Contents Chapter 1 General Information Introduction Features... 5 Chapter 2 Mechanical Installation Mechanical dimensions Connectors Housing parameters... 8 Chapter 3 Hardware Parameters Hardware features Specifications Test standards Environment test standards EMC test standards Electrical performance test standards Chapter 4 Connector Pinouts Connector view Pinout and functions Chapter 5 Function Description Power-down delay Internal circuit control External relay control Switch inputs Analog inputs Hall-effect signal inputs Low-side switch High-side switch H-bridge driver Copyright ECOTRONS LLC Page 3

4 5.8 Communication module Basic introduction CAN wakeup function CAN architecture introduction CAN protocol implementation CCP protocol implementation Torque safety monitoring module Controller hardware diagnosis Chip-level diagnosis Low-side switch diagnosis High-side switch diagnosis H-bridge driver diagnosis Chapter 6 Software Compatibility Production code generation - EcoCoder Powerful calibration software EcoCAL Reprogramming tool Flash GUI Copyright ECOTRONS LLC Page 4

5 Chapter 1 General Information 1.1 Introduction Vehicle Control Unit, or VCU, or Hybrid Control Unit, or HCU, is the core controller for an electric or hybrid vehicle. HCU receives the driver input signals, like pedal inputs, vehicle speed signals, and other inputs, manages the system energy, commands the driver demanded torque, coordinates the motor, battery pack, as well as the conventional powertrain in case of hybrid vehicles, and determines the overall vehicle drivability. HCU is the master of the vehicle control network, or CAN bus based network. 1.2 Features HCU is designed with ISO26262 function safety in mind, and comes with a main chip and a monitor chip built-in, for safety monitoring. HCU comes with the basic software, or BSW, support all typical input / output drivers for vehicle controls. The BSW is encapsulated in the MATLAB/Simulink environment, and the user can develop the control system with 100% model-based-design methods. The HCU hardware is abstracted from the application software and relieves the controls engineer from the challenge of the microprocessor configuration and embedded real-time software. HCU comes with a CAN bus based reprogramming tool, supported by our boot loader which is pre-programmed into the microprocessor. HCU supports the CCP/XCP based calibration tools, like INCA, CANape, as well as the cost effective EcoCAL, developed by Ecotrons. Copyright ECOTRONS LLC Page 5

6 Chapter 2 Mechanical Installation 2.1 Mechanical dimensions The housing dimensions are 207 x 150 x 36 mm. The housing color is silver, made of die-cast aluminum. Copyright ECOTRONS LLC Page 6

7 Copyright ECOTRONS LLC Page 7

8 2.2 Connectors HCU uses the automotive industry rated, "Tyco" brand, connectors. The connector meets the auto safety requirements. The connector has 121 pins total. The following table lists the connector model numbers. No. Name Type Supplier 1 81P sheath TE 2 40P sheath TE 3 Terminal(big) TE 4 Terminal(small) TE 5 81P back TE 6 40P back TE 2.3 Housing parameters Housing size: mm Materials:Die - casting aluminum Waterproof 121-pin connector Good rigidity waterproof breathable vent, good heat dissipation Copyright ECOTRONS LLC Page 8

9 Chapter 3 Hardware Parameters 3.1 Hardware features Main microprocessor Freescale SPC56xx: 150MHz, Flash 4MB, SRAM 192K, float point capable; Monitor microprocessor Freescale S9S08: automotive rated 8-bit low-cost microprocessor; CAN bus: 3 channels; Support CAN wakeup; Sensor 5v supply: 3 channels; Analog inputs: 32 channels, 12-bit ADC, support 13 channels 0-5v inputs,19 channels 0-12v inputs; Digital inputs: 7 channels, support 5 channels 0-5v inputs, 2 channels 0-12v input; Frequency inputs: 5 channels, hall-effect type; Low-side driver: 18 channels, with 16 channels single maximum current is 250mA, 2 channels single maximum current is 7A; High-side driver: 8 channels, the single maximum current is 1.5A; H-bridge driver: 2 H-bridges, single maximum current is 7A, with current limit capability; 3.2 Specifications name parameters Supply voltage DC 12V(9~16V) Working temperature -40~85 Humidity 0~95%, no condensation Storage temperature -40~85 Protection IP67 Copyright ECOTRONS LLC Page 9

10 Mechanical shock Expected life Electric performance EMC Dimensions Weight Peak value is 50g 10 years ISO16750,ISO7637 standards CISPR mm 600g 3.3 Test standards Environment test standards Test items High and low temperature test Temperature shock Charged temperature cycle Splash test Salt spray test Dustproof and waterproof test Vibration test Mechanical shock Test Specific indicators standard ISO hour hour ISO ~ circulation ISO C to -40 C to + 85 C, for a total of 30 cycles per 8 hours ISO After standing at 85 C for 1 hour, the mixture was sprayed with water at 0 C to 4 C for 10 s, followed by 100 cycles ISO Salt solution concentration: 5%, spray sedimentation rate: 1 ~ 2ml / (80cm2 * h). The test was performed in 4 cycles, each lasting 7 days, for a total of 28 days. ISO m deep water, placed for 30 minutes, IP67. ISO The frequency of random vibration is 20 ~ 2000Hz, the root mean square value of the spectrum is 107.3m / s2, the vibration time of X, Y, Z is 8h. ISO The peak value is 50g, the duration for three-axis Copyright ECOTRONS LLC Page 10

11 Constant temperature and humidity Temperature and humidity cycle EH2144A Datasheet V1.2 six-way half-sine impact is 6ms, each 10 times. ISO Temperature +40 Humidity 85% RH normal work for 21 days ISO Low temperature operation and temperature + 23 humidity 93% RH cycle, 24 hours per cycle, 10 cycles EMC test standards Test items Test standard Specific indicators Conducted interference from electronic components IEC CISPR AV and PK meet the four requirements Radiated interference from electronic components IEC CISPR AV and PK meet the four requirements Radiated immunity of electronic components to magnetic fields GMW Frequency Range: Modulation Mode; Intensity: LEVEL2, Function Level A. Electronic components of the electromagnetic field immunity (BCI) GMW Frequency Range: Modulation Mode; Intensity: LEVEL2, Function Level A. CI power supply transient ISO Function level A / C interference CI on the signal line ISO Function level A transient interference Electrostatic discharge (non-live mode) GMW Discharge network: C=150pF R=2kΩ Electrostatic discharge (remote charge mode) GMW Discharge network: C=330pF R=2kΩ Copyright ECOTRONS LLC Page 11

12 3.3.3 Electrical performance test standards Test items Test specification Over - voltage test 36V for 60 minutes Reverse polarity protection test -28 V for 60 ± 6 s AC voltage superposition test U max = 32V, U pp 4V for 5 cycles Supply voltage slow down test U min = 9V linearly decreases to 0V at a rate of 0.5V ± 0.1 / min, and then changes from 0V to U min = 9V Voltage transient drop test U min = 9V, down to 4.5V, continued for 10ms and then rise. Rise, fall time does not exceed 10ms Reset performance test The supply voltage U min = 9V reduced by 5% and maintained for 5s, and then restore the supply voltage to U min = 9V for at least 10s; Repeat the above steps, each time, the voltage reduction increased by 5%, until down to 0%, and then restore power supply U min = 9V. Starting voltage test Simulation of vehicle startup, the voltage fluctuation of the state: the voltage dropped to 6V and continued for 15ms and then returned to normal Power drift test Simulation of two or more groups of power supply, there are different power supply on the product Ground drift test Simulation of two or more groups of power supply, there is a different impact on the product situation Quiescent current Average quiescent current 1mA measurement test Single - wire open circuit test Then disconnect the sample interface connection, each disconnect time to maintain 10 ± 1s, and then restore the connection of the line Multi - line open circuit test Disconnect the sample harness connector, disconnect the time to maintain 10 ± 1s, and then restore the Copyright ECOTRONS LLC Page 12

13 connection of the line EH2144A Datasheet V1.2 Copyright ECOTRONS LLC Page 13

14 Chapter 4 Connector Pinouts 4.1 Connector view The connector has a double row of total 121 pins. The pin numbers are arranged as below. 4.2 Pinout and functions ID Pin # Name Description Remarks 5V1 51 5V supply 1 5V Sensor supply Maximum current is 100mA 5V2 41 5V supply 2 5V Sensor supply 5V3 49 5V supply 3 5V Sensor supply Maximum current is 100mA Maximum current is 100mA A00 15 Analog input0 A01 34 Analog input1 A02 16 Analog input2 0-5V, low effective 0-5V, low effective 0-5V, low effective R_pull_up=5.1K R_pull_up=220K R_pull_up=5.1K Copyright ECOTRONS LLC Page 14

15 A03 35 Analog input3 A04 17 Analog input4 A05 36 Analog input5 A06 18 Analog input6 A07 37 Analog input7 A08 31 Analog input8 A09 71 Analog input9 A11 32 Analog input11 A12 24 Analog input12 A13 43 Analog input13 A14 62 Wakeup signal 1 A15 81 Wakeup signal 2 0-5V, low effective 0-5V, low effective 0-5V, low effective 0-12V,high effective 0-12V,high effective 0-12V,high effective 0-12V,high effective 0-5V, low effective 0-12V,high effective 0-12V,high effective 0-12V,high effective 0-12V,high effective EH2144A Datasheet V1.2 R_pull_up=100K R_pull_up=5.1K R_pull_up=100K R_divider=15K R_pull_down=6.8K R_divider=15K R_pull_down=6.8K R_divider=15K R_pull_down=6.8K R_divider=15K R_pull_down=6.8K R_pull_up=1K R_divider=15K R_pull_down=6.8K R_divider=15K R_pull_down=6.8K For 12V wake up, high effective For 12V wake up, high effective 0-5V, low effective A16 13 Analog input16 R_pull_up=5.1K 0-12V,high effective R_divider=15K A17 52 Analog input17 R_pull_down=6.8K A18 33 Analog input V,high effective R_divider=15K Copyright ECOTRONS LLC Page 15

16 A21 53 Analog input V,high effective A22 10 Analog input V,high effective A23 38 Analog input V,high effective A24 20 Analog input24 0-5V, low effective A25 39 Analog input V,high effective A30 22 Analog input30 0-5V, low effective A31 79 Analog input V,high effective A32 42 Analog input V,high effective A33 23 Analog input33 0-5V, low effective A34 61 Analog input V,high effective A35 80 Analog input V,high effective A36 72 Analog input V,high effective A37 14 Analog input37 0-5V, low effective A39 12 Analog input39 0-5V, low effective BATT1 3 12v power 9-16V EH2144A Datasheet V1.2 R_pull_down=6.8K R_divider=15K R_pull_down=6.8K R_divider=15K R_pull_down=6.8K R_divider=15K R_pull_down=6.8K R_pull_up=1K R_divider=15K R_pull_down=6.8K R_pull_up=220K R_divider=15K R_pull_down=6.8K R_divider=15K R_pull_down=6.8K R_pull_up=220K R_divider=15K R_pull_down=6.8K R_divider=15K R_pull_down=6.8K R_divider=15K R_pull_down=6.8K R_pull_up=220K R_pull_up=220K Copyright ECOTRONS LLC Page 16

17 BATT1 1 12v power 9-16V CANA CANA Shielded 75 SHILD cable CANAH 56 CANAH CANA signal CANAL 55 CANAL CANA signal CANB CANB Shielded 77 SHILD cable CANBH 57 CANBH CANB signal CANBL 76 CANBL CANB signal CANC CANC Shielded 74 SHILD cable CANCH 54 CANCH CANC signal CANCL 73 CANCL CANC signal CAN_Wake 19 CAN Wakeup 0-12V,active high LIN_BUS1 78 LIN Bus DI01 40 Digital input1 0-5V R_pull_up=1K DI02 6 Digital input2 0-5V R_pull_up=220K DI03 25 Digital input3 0-5V R_pull_up=220K DI04 7 Digital input4 0-5V R_pull_up=220K DI05 8 Digital input5 0-5V R_pull_up=220K DI06 65 Digital input6 0-12V R_divider=10K R_pull_down=6.8K DI07 46 Digital input7 0-12V R_divider=10K R_pull_down=6.8K GND 48 Signal ground GND 2 Power ground GND 120 Power ground GND 121 Power ground GND 4 Signal ground Copyright ECOTRONS LLC Page 17

18 GND 5 Signal ground GND 58 Signal ground GND 60 Signal ground GND 70 Signal ground Hbridge1A 118 H-bridge 1A 5A,Peak current7a Hbridge1B 114 H-bridge 1B 5A,Peak current7a Hbridge2A 115 H-bridge 2A 5A,Peak current7a Hbridge2B 117 H-bridge 2B 5A,Peak current7a HSO High-side driver 5 1A,Peak current1.5a HSO High-side driver 6 1A,Peak current1.5a HSO High-side driver 7 1A,Peak current1.5a HSO08 99 High-side driver 8 1A,Peak current1.5a HSO High-side driver 9 1A,Peak current1.5a HSO10 98 High-side driver 10 1A,Peak current1.5a HSO11 94 High-side driver 11 1A,Peak current1.5a HSO12 86 High-side driver 12 1A,Peak current1.5a can be configured to PWM can be configured to PWM DRVP 116 DRVP power of H-bridge 9-16V DRVP 119 DRVP power of H-bridge 9-16V LSO Low-side dirver1 250mA LSO Low-side dirver2 250mA LSO Low-side dirver3 250mA LSO Low-side dirver4 250mA LSO Low-side dirver5 250mA LSO Low-side dirver6 250mA LSO Low-side dirver7 250mA LSO Low-side dirver8 250mA LSO09 91 Low-side dirver9 250mA Copyright ECOTRONS LLC Page 18

19 LSO10 89 Low-side dirver10 250mA LSO11 92 Low-side dirver11 250mA LSO12 95 Low-side dirver12 250mA LSO13 97 Low-side dirver13 250mA LSO14 90 Low-side dirver14 250mA LSO15 96 Low-side dirver15 250mA LSO16 93 Low-side dirver16 250mA LSO Low-side dirver17 7A LSO Low-side dirver18 7A can be configured to PWM can be configured to PWM SPEED1 64 Frequency input1 SPEED2 47 Frequency input2 SPEED3 66 Frequency input3 SPEED4 11 Frequency input4 SPEED5 30 Frequency input5 Maximum frequency 10KHz Maximum frequency 10KHz Maximum frequency 10KHz Maximum frequency 10KHz Maximum frequency 10KHz KEYON 59 KEYON (Digital input) 0-12V,high effective R_divider=15K R_pull_down=6.8K 67 NC 68 NC 9 NC 21 NC 26 NC 27 NC 28 NC Copyright ECOTRONS LLC Page 19

20 29 NC 44 NC 45 NC 50 NC 63 NC 69 NC 82 NC 83 NC 84 NC 85 NC 87 NC 88 NC EH2144A Datasheet V1.2 Copyright ECOTRONS LLC Page 20

21 Chapter 5 Function Description 5.1 Power-down delay The power-down delay of HCU can be controlled by an internal circuit or a relay. The "power-down delay" or "after-run" function, is often needed for control application, where the system need to do some "housing keeping" jobs, after the user keys off the vehicle. For example, the controller will store the critical data into non-volatile memory, or NVM Internal circuit control It is controlled by the internal switch "Power Delay", when the external level of CAN Wake, LIN Wake, KEYON, A14, A15 and the internal Power Delay has a high level, the switch SW1 is turned on. Specific implementation of software: If the external logic level is high, the level of Power Delay is controlled by the internal to high, while the external logic input is low, it will delay for a period of time to turn the level of Power Delay to low. BATT1 CAN Wake LIN Wake KEYON A14 A15 OR OR SW1 VPWR PowerDelay Copyright ECOTRONS LLC Page 21

22 EH2144A Datasheet V External relay control When the power-down delay is controlled by an external relay, the VCU can also control the power-down of other ECUs. Specific implementation: Firstly, keep Power Delay in low level, if KEYON is in high level, the connect of high-side HSOx is controlled by the VCU, if KEYON turn to low level, it will delay for a period of time to disconnect HSOx. The delayed time is calibrated by the software. 12V ECU BATT 12V ECU KEYON DI HSOx VCU 12V 5.2 Switch inputs The digital input module has 7 channels. DI1-DI5 is by default valid for low level input, and DI6-DI7 is by default valid for high level input. Copyright ECOTRONS LLC Page 22

23 5V R Filter GPIO Switching signal Low level input valid 12V Switching signal Filter GPIO R High level input valid 5.3 Analog inputs The analog input module has 32 channels, by default for voltage Inputs. It has 0-5V inputs with built-in pull-up resistors, and 0-12V inputs with built-in pull-down resistors. Copyright ECOTRONS LLC Page 23

24 5V R Filter AD Signal input Pull up Filter AD R Signal input Pull down 5.4 Hall-effect signal inputs The hall signal input module contains five Hall-type speed sensor measurement channels, for either high level active or low level active switching type Hall signal. The default configuration is low level. The user does not need to add an external pull-up (down) resistor because the Hall signal input module has integrated pull-up (down) resistors. Copyright ECOTRONS LLC Page 24

25 5V Hall signal R Filter IPWM Low level active hall input Hall signal Filter IPWM R High level active hall input 5.5 Low-side switch HCU provides 18 Low side switching channels with over-current protection, over-temperature protection and over-voltage protection. 16 channels have 250mA drive current capability. They can detect the load open / short circuit and other failures. 2 channels have 7A drive current capability. They can t detect the load state. And LSO17, LSO18 support PWM output, and you can run pumps and so on. If the pin outputs a high level signal, the corresponding low side switch is turned on; If the pin outputs a low level signal, the corresponding low side switch is turned off. LSO17, LSO18 can be configured to PWM control modes. Copyright ECOTRONS LLC Page 25

26 5.6 High-side switch High side switch module provides 8 high side switch channels with short circuit protection, over-temperature protection and over-voltage protection, the maximum current is 1.5A. If the IO output is high level, the corresponding high side switch is turned on. If the IO output is low level, the corresponding high side switch is in the off state. HSO11, HSO12 can be configured to PWM control modes. Copyright ECOTRONS LLC Page 26

27 5.7 H-bridge driver HCU has a built-in H-bridge. It has two outputs, and the maximum current support is 7A, with current limiting function. It can be configured to switch mode, or PWM mode. Copyright ECOTRONS LLC Page 27

28 5.8 Communication module Basic introduction CAN communication module provides three CAN channels, as we called them CANA, CANB, CANC; and all of them are CAN2.0B high speed bus. CANA and CANC have a default terminal resistance, CANB does not. CANA and CANB are two public CAN channels opened to the users. Generally used for vehicle network protocols. The default CAN configuration is compatible with J1939, and the default baud rate is 250K and the CAN IDs are default the extended frame. All these defaults can be configured by the users. The CAN protocols can be J1979 or ISO15765 Copyright ECOTRONS LLC Page 28

29 compatible, and the baud rate can be 500k or 1M; and the CAN IDs can be standard frames. CANC is for calibration purpose, default for the CCP protocol, and it s used for updating the controller program, as well as calibration and measurement. PC 120Ω CANCH CANCL Driver Driver Driver CAN Bus 120Ω CANAH CANAL CANBH CANBL CAN Bus CANH CANL CANH CANL CANH CANL CANH CANL 120Ω 120Ω 120Ω CAN Node CAN Node CAN Node CAN Node CAN wakeup function CANA support CAN wakeup function, VCU can be waked up by CANA. When KEYON signal is off, the VCU is power down. If other nodes send messages to CANA bus, the VCU will be waked up after receive messages, then VCU goes into working mode. CAN wakeup function can be used for VCU remote wakeup from other nodes, or from remote intelligent terminal. Copyright ECOTRONS LLC Page 29

30 5.8.3 CAN architecture introduction In order to support the application layer protocol, CAN communication module is set to some layers. Below are the details: (1) Drive layer: the data link layer of communication model, including the IO drivers and CAN driver of the microcontroller. (2) Abstraction layer: the network layer of communication model. It needs to choose the CAN corresponding IO, provide CAN initialization, CAN transmitter and CAN receiver interface for the service layer. (3) Service layer:the interactive layer of communication model. The implementation of this layer is based on the interface function provided by the abstraction layer, with the Simulink model and s-function to achieve. (4) Application layer:for the signal or the s-function provided by the service layer to protocol specific implementation. Application Layer CCP Broadcast protocol Service Layer CAN interface CAN transceiver driver IO driver CAN driver Abstraction Layer Driver Layer Microcontroller CAN protocol implementation The specific implementation of application layer can use the DBC file or MATLAB m Copyright ECOTRONS LLC Page 30

31 file to import the definition of protocol matrix. The code generation process is as the below: DBC file DBC Converter M file CAN matrix CAN pack CAN unpack S-Function CCP protocol implementation CAN Broadcast Protocol Model Target Language Compiler CAN Broadcast Protocol C Code CCP service function, DAQ definition and storage page configuration are implemented in the c code, or low level software; while the station address, DTO ID, CRO ID and other basic parameters can be configured in the s-function. Copyright ECOTRONS LLC Page 31

32 CCP parameters S-Function The CCP library Target Language Compiler CCP service functions, DAQ definition, reference page definition, work page definition,etc. Communication parameters A2L CCP Initialization, CCP functions call. C Code 5.9 Torque safety monitoring module The design of HCU is based on advanced safety monitoring concept. It uses master-slave chip architecture to assure the safety of the system, as shown in Figure, the master chip is a 32-bit microcontroller SPC56xx, the slave chip is a 8-bit S9S08 automotive chip. Three-level architecture Copyright ECOTRONS LLC Page 32

33 Level 1:Vehicle control functions, including all vehicle control functions and fault diagnosis. Level 2:this is to monitor the Level 1 by a redundancy design, and it is independent to the Level 1. If there is discrepancy between Level 2 and the Level 1, Level 2 will make the torque command in the CAN bus message Neutral. Neutral means no hazard acceleration. Level 3:By adding a slave chip to monitor the master controller, the 2 chips cross check each other. If the handshake fails, it will neutralize the torque command, so it does not create hazard situation. Copyright ECOTRONS LLC Page 33

34 5.10 Controller hardware diagnosis Chip-level diagnosis Support Flash and RAM diagnostics of the master chip. Support kernel self-test diagnostics of the master chip. Support diagnosis of the slave chip Low-side switch diagnosis LSO1-LSO16 are the output channels of the low-side driver circuit. These channels support the fault diagnosis function. The fault diagnosis is based on the integrated chip diagnosis. Use the integrated chip with the diagnostic function, you can read the chip fault information through SPI communication, below is the supported diagnosis of fault information provided by the chip: Copyright ECOTRONS LLC Page 34

35 High-side switch diagnosis The high side drive circuit output channel is HSO5-HSO12,it doesn t support high side drive circuit fault diagnosis H-bridge driver diagnosis H-bridge circuit fault diagnosis uses the integrated chip with the diagnostic function, you can read the chip fault information through SPI communication, below is the supported diagnosis of fault information provided by the chip: Copyright ECOTRONS LLC Page 35

36 Chapter 6 Software Compatibility MATLAB/Simulink based software development environment. Model based design. Enhanced Auto code generation EcoCoder. o Refer to " EcoCoder Manual V2.3". Hardware encapsulation and abstraction One click compile and make process. CCP/XCP protocols. Powerful calibration tool EcoCAL. o Refer to " EcoCAL manual for EV ". Commercial compiler Code Warrior. Compatibility with INCA, CANape calibration software. CAN bus based boot loader Flash GUI tool. Copyright ECOTRONS LLC Page 36

37 6.1 Production code generation - EcoCoder EcoCoder is an enhanced auto code generation library added on top of Simulink s generic Embedded Coder. It links the Simulink s models directly to the target, and it gives the user the capability to generate the production code by "ONE CLICK". Refer to our " EcoCoder Manual V2.3" for details. Copyright ECOTRONS LLC Page 37

38 6.2 Powerful calibration software EcoCAL EcoCAL is a professional calibration tool, developed by Ecotrons. It is based on the CCP/XCP protocols, and uses the CAN bus for data communication. It parses the standard A2L files, and manages the calibration data in the format of S19 files, Mot file or CAL file. Refer to our " EcoCAL manual for EV " for more details. Copyright ECOTRONS LLC Page 38

39 6.3 Reprogramming tool Flash GUI Flash GUI is a simple PC based GUI software tool to reprogram the controller, developed by Ecotrons, using CAN bus for reprogramming, with a typical boot loader pre-programmed in the microprocessor. Copyright ECOTRONS LLC Page 39