HEM Data » Old DAWN FAQs

The Logger Panel is an extended option with DAWN. It is most often used with a modem for remote control but can also be used when directly connecting the PC to the logger.

Remote Logger by Cellular

Will we need a static IP address?

No. We keep track of the modem by its name and have a DNS server that updates its IP Address as it changes. You just contact it by its name.

How much data would you project that we need in a months time for 1 vehicle?

Calculate the number of points using Sample Rate * Duration per test * No. of Channels * No. of Tests in a month. Multiple by 4 bytes/point to calculate storage size in bytes.

What are the requirements for a FTP site?

Almost any FTP site should work but they all don’t work. We do not know why. It seems the only way to know is by trial and error. We worked with one customer’s IT department and tried 6 sites; 3 worked and 3 didn’t. The logger only has a TFTP (Trivial FTP) server which means it does not have provisions for a password but most FTP sites require a password. ESM does send the password even though it is not part of the TFTP spec and some FTP sites accept this and some do not. You can try your site to see if it works by filling in the dialog with the site name/IP address and password.

CAN Messages

Can you explain the headings of the columns on the HEM message log?

The priority in the header is 00007. So ignore columns B-E.

Col F=7 is the priority. The test tool has the lowest priority at 7. Zero is the highest.

General CarDAQ-Plus / CarDAQ AVIT

Do we need Ethernet to connect to AVIT or can we use USB?

Ethernet unless you are working with a new model.

I am trying to tell when the logger is collecting data, when it is suspended, etc.

The upper left light should be blinking to designate that eSM is loaded.

Lower left (amber) light shows when it is acquiring data.

Upper right initially shows when it is connected to a PC. It will then display when storing data to the CF card.

The last two lights will go on and off together unless there is a trigger specified. The amber light could be on but if the trigger condition is not met then there will be no data storage and upper right light will be off.

Bottom right will show an error but hopefully you won’t see this.

A cautionary note: if eSM crashed the lights will still be blinking so it appears all is working but there is now no control of the lights.
The way to manually check this is to press the button which should toggle the logger to stop. If the lights go off, then eSM is working. Pressing it again re-starts eSM. If it is unresponsive, then reboot the logger (re-power). The Logger Panel will provide a message that eSM cannot be found, if eSM has crashed. You will then need to rebbot the logger with Telnet.

All of the files we collected have very odd time/date stamps (for example: 12/31/1969 5:00 pm). This information appears to be present on the file attributes and a slightly different time/date stamp is in the SMA file. Any idea if this is normal behavior or a bug?

The AVIT hardware does not have a battery backup on its clock (sold prior to 2010), so each time you unpower the box, it reverts back to 1969. Many of our users have a GPS unit to keep track of time in the case where the logger is typically unpowered.

The other typical case is that the logger shuts down to a lower power state and it still keeps track of time as long as it remains powered.
You can use Telnet to set the clock with the following commands:
date -s ‘2009.09.17-14:43’ .
That is ‘year.month.date-hours:minutes’
Type hwclock -w -u .
Now the date is set and will remain set until the unit is unplugged.

Acquiring Data with CarDAQ Plus/AVIT

The manual suggests that I should set a very long frame duration (hours). If I do this and I use the Wake line to suspend data logging and then put the logger to sleep, will the logger pick up logging the same frame when it wakes up?

No. The banana jack input is only there to awaken the box and is ignored once the box is awake. The logger goes to sleep typically because there are no more messages detected after N seconds.

Will it write data it has to CF on Sleep and start a new file on Wake?

A separate data file is written for each cycle. The writing to file occurs in real-time, not as a post process.

It appears that the data is lost if the logger is powered off during the logging process. Is this normal?

Yes, the assumption is that the logger is stopped prior to losing power. As you see, it is very risky to cut the power while the unit is in the middle of writing a data file.
You can either stop it with the analog signal on channel 1, look for no messages, or both (AND condition). You can shorten the delay to shutdown as defined in DawnConfig.exe (written to c:\sm\dawn.ini which is a text file).
If you are using the ignition signal to stop the logger and switch the power to the logger, you need to add a delay in line to power it down or have the user manually disconnect the logger from the power.

VIN Support

Why does DAWN detect the VIN on only some of my test vehicles?

VIN is only required to be supported for MY 2005 and later vehicles. Before then it was at the OEM’s dicretion.

Old DAWN FAQs

The Remote Control panel is referenced in the manual. The file is missing (although the directory exists) from my install.