sl2format

node-sl2

Module to read .sl2 files, generated by Lowrance chart plotters as a stream.

I/O

Input from for example file stream for an .sl2 file Outputs block objects looking something like this.

{
  frameIndex: 0,
  blockSize: 3216,
  packetSize: 3072,
  lastBlockSize: 0,
  channel: Primary,
  time1: 3536977920,
  waterDepth: 6.622000217437744,
  temperature: 19.350006103515625,
  frequency: 0,
  keelDepth: 0,
  upperLimit: 0,
  lowerLimit: 19.600000381469727,
  altitude: 118.89765930175781,
  heading: 0,
  courseOverGround: 3.7873644828796387,
  waterSpeed: 0,
  gpsSpeed: 2.585312843322754,
  longitude: 1383678,
  latitude: 8147302,
  flags: {
    trackValid: true,
    waterSpeedValid: false,
    positionValid: true,
    waterTempValid: true,
    gpsSpeedValid: true,
    altitudeValid: true,
    headingValid: false
  }
}

File format

• https://github.com/kmpm/node-sl2format/blob/master/doc/sl2fileformat.md
• http://wiki.openstreetmap.org/wiki/SL2

Licence

MIT