SkyTraq Venus based loggers (download) (skytraq)
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## SkyTraq Venus based loggers (download) (skytraq)

This format can...

- read waypoints

- read tracks

This format has the following options: erase, targetlocation, baud, initbaud, read-at-once, first-sector, last-sector, dump-file, no-output .

Serial download protocol for GPS data loggers based on Skytraq Venus 5 and Venus 6 chipsets. This chipset is used by a number of devices from different manufacturers. If your logger came with the Windows software iTravelTech GPS Photo Tagger, chances are that you can use this format to read its memory.

Following a list of devices which should be supported by this module (Note that not all of them have actually been tested, so if you can confirm that additional models work, please mail the gpsbabel-misc group with your success, tips, and any pertinent links for your model.):

Table 3.7. Devices supported by skytraq module

Manufacturer | Model | USB (baud) | Bluetooth (baud)
--- | --- | --- | ---
SJA | "3-in-1" GPS logger | up to 230400 | 9600
Navilock | BT-455PDL | untested | untested
Polaris | Travel Honey | up to 230400 | 9600
Pearl Diffusion | Keymate STV-5 | untested | untested
Canmore | GT-750F | untested | untested
Adapt Mobile | Keychain Pro | untested | untested

Example 3.29. Command showing skytraq download of tracks and erasing the logger on Linux

`gpsbabel -i skytraq,erase -f /dev/ttyUSB0 -o gpx -F out.gpx`

Example 3.30. Command showing skytraq erasing the logger without download on Linux

`gpsbabel -i skytraq,erase,no-output -f /dev/ttyUSB0`

If available, reading the logger using bluetooth should also work. However, many devices support only one specific baud rate over bluetooth, e.g. 9600. In that case you should use the option `baud=0` to tell GPSBabel to use that default baud rate:

Example 3.31. Command showing skytraq download tracks via bluetooth on Linux

`rfcomm bind 0 <bdaddr>`

`gpsbabel -i skytraq,baud=0 -f /dev/rfcomm0 -o gpx -F out.gpx`

### `erase` option

Erase device data after download.

### `targetlocation` option

Set location finder target location as lat,lng.

The device provides a location finder built from eight LEDs and can use those LEDs to guide you to a location. You can set the target location with the 'targetlocation' option. Use ':' as the delimiter between latitude and longitude. Note that GPSBabel terminates after writing the location info to the device, i.e. no logging data will be read from it.

Example 3.32. Set the target location of the Skytraq location finder

`gpsbabel -i skytraq,targetlocation=12.34:-56.78 -f /dev/ttyUSB 0 -o unicsv -F -`

Sets latitude and longitude of the location finder to N12.34 and W56.78 respectively. The arrows on the device will point you to this location as soon as it has a satellite fix.

### `baud` option

Baud rate used for download.

The following baud rates can be used: 4800, 9600, 19200, 38400, 57600, 115200, 230400. Note that your logger might not support all of them (especially 230400 which isn't documented in the chipset manual, though there are known devices that are capable of this speed).

If `baud=0` (zero) download takes place at the baud rate the device is currently set to. This is especially useful for Bluetooth connections since they often don't allow changing the baud rate.

### `initbaud` option

Baud rate used to init device (0=autodetect).

The "initbaud" option might be helpful if autodetection fails or takes too long. With this option you can tell GPSBabel the baud rate the device is currently set to. In contrast, the option "baud" specifies the rate at which the actual download should take place. If it is different than "initbaud" (or the autodetected rate, if initbaud wasn't given), the initial setting will be restored after finishing the download.

### `read-at-once` option

Number of sectors to read at once (0=use single sector mode).

If `read-at-once` >= 1, batch mode is enabled with that many sectors being read at a time. A value of zero disables batch mode and switches to single read mode. Not all devices support batch mode; in that case gpsbabel automatically switches to single read mode.

Under normal circumstances, the larger this number the faster the transfer. Reducing `read-at-once` or even switching to single sector mode might help when you get transmission errors/aborts.

### `first-sector` option

First sector to be read from the device.

The logger's memory is organized in sectors, serially numbered starting at 0. Each sector takes 4096 bytes of data. Typical devices hold about 250 sectors. The memory is always filled from sector 0 on, until it is full or the device being erased again by the user.

Normally you can safely omit this option. However, it might be useful to read data from erased devices: we observed that on erase, only the first two sectors are actually cleared. The following example shows how to read the remaining data:

Example 3.33. Command showing how to read data from an erased device

`gpsbabel -i skytraq,first-sector=2 -f /dev/ttyUSB0 -o gpx -F out.gpx`

### `last-sector` option

Last sector to be read from the device (-1: smart read everything).

A value of -1 (the default) enables automatic mode, i.e. reading is stopped when an empty sector is encountered. We observed that sometimes the device doesn't report the correct number of used sectors, which confuses the Windows software, so that it might not get all trackpoints. In contrast, our algorithm ensures that everything is being read (please report if it doesn't work for you).

### `dump-file` option

Dump raw data to this file.

Writes raw data as it is read from the logger to the file given as this option's argument (additional to decoding it as usual). The resulting binary files can be read and decoded by the skytraq-bin format. Mainly useful for debugging/development purposes.

### `no-output` option

Disable output (useful with erase).

If this option is given, no GPS log data will be read from the device (unless "dump-file" is given too; in that case only decoding will be disabled).

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