In addition to ignition, power and monitoring gauges and lights, today's motor vehicles feature computerized engines, transmissions and braking systems, electronic mapping systems, Bluetooth and Internet connectivity, sensors that detect other vehicles, motorized seats, and digital audio and video systems; several manufacturers are producing electric and hybrid automobiles and self-driving cars.

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Attached is CAN Transceiver Datasheet.  This IC is wired in our Microcontroller based Electronic Control Unit.
Page 5 shows the pinout.  How to measure current at BAT Pin ?  Current Probe can be clipped to wire but this is IC Pin.
The image shows the position of the door locking mechanism. That part will not turn the proper way to allow the doors to be closed. When the engine is running and the power door lock button is pressed, the 4 door locks try to close but fail and stay open. When the engine is turned off, the master door lock on the left side door can be pressed and it closes the door locks on all 4 doors. By door lock I mean the manual switch on the arm rest will close. Then the doors can be closed manually and the car is locked. The left side door does not close. If an effort to examine the right front door, we have the lock part in the same position and can not get it back like normal. So we have two doors that won't close fully which makes the red lights on the dash go off. The light that says a door is open. We have to use bungie cords to keep the doors as closed as we can with the tension and we have to unhook the battery since the two doors are not closed.

edit: I watched a video on such a door lock. When the door handle outside was raised the mechanism seen does rotate back to the normal position so the door can be closed. Whether this can be done with the battery not hooked up is not known. I'll try to raise the right outside door handle because that is the one that I used a screwdriver to lock the mechanism. It may then be able to the closed. The left side is the one which developed the symptom the earliest.
My computer is running Windows 10 Pro, 64-bit.  My C language files or my code (program) are stored in the hard disk.  

The old and new version of WindRiver Diab Compiler are stored in Linux Server?

My bash profile used to contain path to old compiler.  To compile, I ran Winscp to access Linux Server.  Then, I dragged my C language project to Linux Server.  I opened the command window from Winscp and invoked make program to build my executables.  This all worked fine.

To build with new compiler, I changed path in my bash profile but my code (program) is still getting build with old compiler.  The generated .map file shows path to old compiler.

My bash profile is stored in my windows desktop.  Does Winscp read bash profile when it is invoked?  How does it know to read bash profile from desktop?  Why is my program not getting built with new compiler?
Following is what some source says about Autosar OS Multicore Support:

1.  Communication via shared memory.  Spinlocks are used for critical sections.

2.  You can not share resources between cores.

Isn't this contradicting ?   I believe memory is a shared resource.  If the memory can not be shared between cores, then, how can they communicate via shared memory?
I'm creating C language controller application that will run on host.  The purpose of this application is to control Lauterbach Trace32 Debugger remotely.  

To achieve this remote control, controller application will call Lauterbach C language APIs.  These APIs will be commands that will be sent over UDP Socket to Trace32 Debugger Software.

Controller Application and Trace32 Debugger Software are running on the same host.  The APIs is a C language library that will be linked with the controller application.

I want to send command to write a value to a integer variable.  This means I need to pass pointer to integer but API is expecting char *
Please see Page 81 of attached document.  API is T32_WriteVariableValue ( )

i would like an answer to this Questions :
i have a diesel VW Passat 1900
when i start the car  -it uses a lot of power from the battery
Questions :
- how many times can i start without leaving it running approx?
-  how many km's must i run before it's fully charged - in a townlike environment - approx; or how long in time must it run
I have 2003 Chevy Silverado 5.3 L V8. I have been using this vehicle since 2006. I took it to a some small auto shops to look at the radiator and other rubber hoses make sure they are in good shape. They told me it looks ok accept the firestone. They told me it looks old you need to change them. Dealer charge 120 dollars for the pressure test. I just don’t know should I blow my 120 bucks or just drive it. It has over 180,000 miles on it.
I have coded the calculation of the classic checksum of 8 bytes of data 0x01,0x06,0xB2,0x22,0x31,0x00,0x53,0x4F which should result in 0x50 as the result. My code yields an answer of 0x51 however, where am I going wrong ?

      unsigned char a[] = {0x01,0x06,0xB2,0x22,0x31,0x00,0x53,0x4F};
      unsigned char cksum = 0;

      for(int i=0;i<8;i++)
      cksum = ~cksum;
A typical embedded system, let's say Transmission or Power Train Electronic Control Unit (ECU) is powered by automobile Battery.

Battery voltage is at 12 Volts.  If the battery voltage drops to 0 Volts in 5 us and stays at 0 V for 100 us, then rises back to 12V in 5 us, what impact will this have on Microcontroller memories, different microcontrollers inputs like Analog, Digital, PWM, etc.  And different outputs like Digital, PWM etc.  

Will the contents of I/O and memories like SRAM, Program Flash, Data Flash change due to this transient?

The microcontroller on the ECU is Infineon Aurix TX29x.
I have a specification from a customer regarding communications with a Slave device on a LIN bus system. I am writing an application that acts as the master device on the LIN bus.
The customer specification defines the Protected ID for each of two slave devices as 0x80 and 0xC1 which, as far as I can see are invalid as the most significant two bits of the Protected Identifier field are parity bits which leaves value in the range 0 to 0x3F as possible valid values for the Protected ID.
The specification specifies LIN version 2.1 using Unconditional frames.
I have no prior experience with LIN bus communications, can someone please comment or correct my understanding of the meaning of the Protected ID field and valid ranges of values ?
Need a battery guide for 1991 Honda Accord.

Relative bought a new battery from AAA. $138.00. Now less than a year later the battery is 316 CCA when it is supposed to be 650. The car owner keeps falling for tricks by AAA. They (AAA) took this same battery and charged it over night and brought it back out.

This person only drives their car 2-3 times a month. That is part of the issue. They say they are tired of dealing with the problems and want to buy a new battery. A new battery will run down too.
I found something defective in the right turn signal system. The turn signal blinks too fast. A bulb could be bad and one of the broken filaments could be touching metal.

AAA has a 3 year warranty on their batteries and it looks it is a replacement and not money back.

The battery was first installed August, 2015. There is a sticker on the battery that says 8/15. Another one says 1/16.
I'm using WindRiver Compiler to cross compile large embedded 'C' language project.

The source code is in the hard disk on my windows computer.  The compiler is in Oracle Linux Server.

I invoke WinSCP to access Linux Server.  Now, there are Two Windows on my screen.  Window on the left has my windows directory tree.  Window on the right has my Linux directory tree.  I drag source code from my Windows machine to Linux Directory Tree.

WinSCP comes with a command shell.  I invoke make program from the command shell.  The compiler starts executing because I see dcc command on the command window.  It tries to compile first .c file but object file or .o file isn't created.  The error message is as follows:

"/tmp/dtmpBAAa25644", error:  cannot create output file  ./BOOT/Object/filename.o

Why?  Do I lack some permissions in Linux Server ?
I need to learn sufficient Linux to be able to compile large Professional 'C' language Project?

The compiled executable will be loaded and executed in a Electronic Control Unit?

How to learn Linux?
I had to have someone come out and jump my vehicle because the battery was dead due to cold temps.  It was totally dead.  Would not turn over.  They did get it started but my question is how can I keep my car from going dead again this winter.  This truck sits outside and does not get used for 2 weeks at a time.  I assume that the next time we get cold temps for a bit it will go dead again.  Would a trickle charge hooked up to the battery on the nights that are going to be really cold help or is there another alternative to help?
GNU Make Manual talks about Top Level Make and sub-make.

What is sub-make ?
My computer is running Windows 10 Pro, 64-bit.  My C language files are stored in hard disk.  The WindRiver Diab Compiler is stored in Oracle Server?

What is Oracle Server?  And why is compiler stored in Oracle Server?
I would like to use SVN Command Line Client?  Is it called SlikSVN?

From where can I download it?
Scanner shows right rear ABS sensor bad. Replaced sensor and reset but still bad. Put the sensor I replaced on left rear and it checks good so problem was not sensor or ring. Any suggestions on how to check wiring between connecter at sensor and control module. Can't seem to find wiring diagram that points to next connection.
A particular embedded 'C' software uses FLOAT and DOUBLE.  

The range and scalings for FLOAT and DOUBLE values are defined in ANSI / IEEE Std 754.  How can I access and understand this information?
In every professional embedded 'C' code, there are atomic operations and interrupts are disabled during execution of atomic operations.

Please provide several examples of atomic operations and why interrupts need to be disabled during execution of atomic operations?
Anyone can suggest several Japanese hybrid 6/7-seater cars that comes with power cords to
charge from the wall power points at home?
Is there any of the Stream or Odyssey models that come in Hybrid (ie with battery to drive)?
If so, specify the model(s)

Which of the model allows me to set the speed, say 110km/h & all I need to do is control
the steering wheel?  It feels tired to press my foot for 5-7 hrs continuously on the accelerator
Does any one knows any mini spy rotating camera which I stick on the dash board of one of my junk car sitting outside in the wood and can monitor through remote control from my room,
A typical car has many Electronic Control Units(ECUs) or modules.

"When diagnosing bus or module communication problem, you usually  start by checking for voltage at the module, then the ground connection, and finally the data line."

Measuring module voltage is easy.  Just measure voltage with respect to ground.

How do you check the ground connection?  Is the module ground always at zero volts?
The purpose of Instrument Panel Controller in a car is as follows:

"Instrument panel ---  There is a microprocessor chip built on the back of the instrument cluster that receives signals from hardware and controller area network (CAN) to display driver information and to act as a gateway between high and medium speed CAN."

What does it mean to act as a gateway between high and medium speed CAN and how does instrument cluster  do that ?


In addition to ignition, power and monitoring gauges and lights, today's motor vehicles feature computerized engines, transmissions and braking systems, electronic mapping systems, Bluetooth and Internet connectivity, sensors that detect other vehicles, motorized seats, and digital audio and video systems; several manufacturers are producing electric and hybrid automobiles and self-driving cars.