Class: GPS_PVT::UBX

Inherits:
Object
  • Object
show all
Defined in:
lib/gps_pvt/ubx.rb

Constant Summary collapse

GNSS_ID = 
{
  :GPS => 0,
  :SBAS => 1,
  :Galileo => 2,
  :BeiDou => 3,
  :QZSS => 5,
  :GLONASS => 6,
}
SIGNAL_ID = 
{
  :GPS      => {:L1CA => 0, :L2CL => 3, :L2CM => 4},
  :SBAS     => {:L1CA => 0},
  :Galileo  => {:E1C => 0, :E1B => 1, :E5_bI => 5, :E5_bQ => 6},
  :BeiDou   => {:B1I_D1 => 0, :B1I_D2 => 1, :B2I_D1 => 2, :B2I_D2 => 3},
  :QZSS     => {:L1CA => 0, :L2CL => 4, :L2CM => 5},
  :GLONASS  => {:L1OF => 0, :L2OF => 2},
}

Instance Method Summary collapse

Constructor Details

#initialize(io) ⇒ UBX

Returns a new instance of UBX.



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# File 'lib/gps_pvt/ubx.rb', line 34

def initialize(io)
  @io = io
  @buf = []
end

Instance Method Details

#each_packet(&b) ⇒ Object 



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# File 'lib/gps_pvt/ubx.rb', line 99

def each_packet(&b)
  res = Enumerator::new{|y|
    while packet = read_packet
      y << packet
    end
  }
  b ? res.each(&b) : res
end

#read_packet ⇒ Object 



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# File 'lib/gps_pvt/ubx.rb', line 64

def read_packet
  while !@io.eof?
    if @buf.size < 8 then
      @buf += @io.read(8 - @buf.size).unpack('C*')
      return nil if @buf.size < 8
    end
    
    if @buf[0] != 0xB5 then
      @buf.shift
      next
    elsif @buf[1] != 0x62 then
      @buf = @buf[2..-1]
      next
    end
    
    len = (@buf[5] << 8) + @buf[4]
    if @buf.size < len + 8 then
      @buf += @io.read(len + 8 - @buf.size).unpack('C*')
      return nil if @buf.size < len + 8
    end
    
    ck_a, ck_b = UBX::checksum(@buf, 2..(len + 5))
    if (@buf[len + 6] != ck_a) || (@buf[len + 7] != ck_b) then
      @buf = @buf[2..-1]
      next
    end
    
    packet = @buf[0..(len + 7)]
    @buf = @buf[(len + 8)..-1]
    
    return packet
  end
  return nil
end

#read_packets ⇒ Object 



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# File 'lib/gps_pvt/ubx.rb', line 108

def read_packets
  each_packet.to_a
end