Log2EWT

Download Log2EWT.exe
This software is covered by my freebie licence.


Purpose

Sometimes it is convenient to upload traces from EW Flight Recorders to computers which cannot run the EWView/DOS or EWView/Windows software. Examples might include Windows CE and other palmtop computers and Apple Macintosh machines. Perhaps the user has one of these available as a portable computer with an MS-DOS or Windows machine at base but doesn't wish to remove the flight recorder from the glider as it may be required by syndicate partners before it can be returned.

In these circumstances the trace can be uploaded to the portable computer and stored in a text file using a suitable terminal emulator with a logging function. It can later be transferred to the machine with EWView and converted to EWView's internal format (.EWT) using Log2EWT.

Applicability and Limitations

This software can be used with traces from EW Flight Recorders with model letters A, B or C. (The model letter appears in the middle of the FR's serial number between the four digit date code and the four digit number of the unit). Log2EWT cannot be used with model F (French) FRs or model D ("miniature", no keyboard or display) FRs and will probably not be applicable to any further models produced.

Certain functions which EWView/DOS can be configured to perform on trace upload are not supported by Log2EWT. Log2EWT is not able to set the comment text of the trace depending on the serial number of the flight recorder or other aspects of the trace in the way which EWView/DOS can.

Log2EWT does not have the option to automatically export the trace after the EWT file has been written - unlike EWView/DOS where this function is typically used to create a .IGC file automatically.

The EWT file format contains a field to store the computer's clock date and time at the time of upload. Log2EWT sets this to the date and time of the conversion and so it cannot be used to correlate with the flight recorder's clock settings in the trace which are those applicable at the original time of the upload. These fields are written to EW specific logbook records in the .IGC file and are not otherwise available. No known software makes use of this information though it may occasionally be used by manual inspection of the .IGC file.

Log2EWT is a 16-bit DOS program and so it is restricted to dealing with "8.3" format file names.

Installation

Download Log2EWT.exe to the machine on which EWView is run and save it in a suitable directory. The directory in which the .EWT trace files are stored would probably be suitable.

Connection

Setting up particular computers and terminal emulators is beyond the scope of this documentation.

You will need a lead which makes the following connections between the 9 pin female connector on the flight recorder and the serial port of your computer:

Computer Serial Port Flight Recorder
Transmit Data Pin 2: RX
Receive Data Pin 3: TX
Signal Ground Pin 5: GND
Handshake Output Pin 8: CTS

The connection from Transmit Data to Pin 2: RX can be omitted if all commands are to be given to the Flight Recorder through its keyboard.

The handshake connection to Pin 8: CTS should be held in the positive, on, spacing condition when the FR can send to the computer and in the negative, off, marking condition when it should wait.

The handshake connection can be omitted if the receiving computer is fast enough not to require any form of flow control without loss of characters but Pin 8 must be held in the positive state in this case. A connection to Pin 7: RTS would be a suitable method of doing this.

Be sure that the computer really is fast enough, though, otherwise characters may be lost and Log2EWT will not be able to convert the trace resulting in great distress. A test with a long trace is recommended.

Avoid connections to the other pins of the FR as some of these have signals which are not compatible with normal serial ports. In some cases damage to the port or FR could result from such connections. Note that many standard, off-the-shelf, leads will make such connections.

Upload

The terminal emulator should be set for 9600 baud, 8 data bits, no parity with suitable hardware handshake if Pin 8: CTS is connected as discussed above.

Logging to a file should be selected. A suitable filename extension, if applicable, would be .LOG as this is the default for Log2EWT.

The traces can then be uploaded from the FR just as if they were being sent to a printer. Turn the FR on and press PRT to put it in print mode. You should then see the EW Barograph main menu on the terminal emulator screen.

Operation can be completely from the FR's keyboard. Alternatively, keystrokes can be sent via the terminal emulator. The following equivalences apply:

Flight Recorder Key Computer Character
0..9 Digits '0'..'9'
ON/ENT Enter/Carriage Return
YES Letter 'Y'
NO Letter 'N'
OFF Letter 'O'

Note that the letters must be sent as uppercase (capitals).

(There are actually two other letters which may be sent. Lower case 'd' causes the FR to dump its memory contents in hexadecimal for debugging purposes and lower case 'x' initiates uploads using the XModem protocol - however there is currently no software to decode the resulting file.)

Follow the FR's menus to list the traces and select the trace to be "printed". Select numerical printing of the trace but not graphical printing. If you select graphic printing you will cause great confusion to both the terminal emulator and Log2EWT.

Once the trace has been uploaded turn off the flight recorder or select another trace for upload. If the log file contains more than one trace eventually each will be stored in its own .EWT file by Log2EWT.

It doesn't matter if the various menu options to select the trace, etc, are stored in the log file. Log2EWT will skip all lines up to the "EW Barograph - serial number" line which indicates the start of a trace and stop processing that trace on the "Security: " or "Pilot's name:" line - at which point it will start looking for the next trace.

After the log file containing the trace(s) has been created it must be transferred to the computer with Log2EWT. How this is done is beyond the scope of this document.

It is worth noting that Log2EWT is not too fussy about end of line conventions. It expects each line to consist of from zero to 80 characters followed by zero or more carriage return characters followed by a line feed character. Extra blank lines are not significant.

Therefore files following the DOS convention (carriage return, line feed between lines), the Unix convention (just a line feed between lines) or even some word processor output files (using carriage return, carriage return, line feed to indicate the difference between soft and hard end of lines) are all acceptable. Lines from the FR should not be split, however.

Conversion

Once the log file containing the trace(s) has been transferred to the EWView machine it can be converted to the .EWT format using Log2EWT. If the log file is called "traces.log" the following command would do this:

C:\EWVIEW\>log2ewt traces

As it runs Log2EWT displays information on its progress. In particular it displays the header lines from each trace processed together with the name of the .EWT file created.

The input file (that is the log file) is specified on the command line. If no file name extension is specified then ".LOG" is added. To process a file which has no file name extension specify this by giving just a dot after the file name (e.g., "traces.").

Only one log file can be specified.

The .EWT files are always created in the current directory using the same naming convention as EWView/DOS.

The following command line switches can be specified in either upper or lower case by prefixing them with "-" or "/":

Switch Meaning
 h or ?  Give brief help, mostly a reference to this document.
 i  Take the log file from standard input instead of a file named on the command line.
 v  Display program version number.

Program Revision History

 9902AX 
  • Initial release.
 9950AX 
  • Updated modules shared with EWView/DOS with more specific compilation options to reduce amount of code compiled into program but not used.
  • Added '-?' command line switch for help information (in addition to '-h').