Parallax VPN1513, Руководство пользователя

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VTG-Course Over Ground and Ground Speed $GPVTG,309.62,T,,M,0.13,N,0.2,K*6E
Name Example Units Description
Message ID $GPVTG VTG protocol header
Course 309.62 degrees Measured heading
Reference T True
Course degrees Measured heading
Reference M Magnetic
Speed 0.13 knots Measured horizontal speed
Units N Knots
Speed 0.2 Km/hr Measured horizontal speed
Units K Kilometers per hour
Checksum *6E
<CR><LF> End of message termination
2.2 NMEA Input Command
A)
. Set Serial Port ID:100 Set PORTA parameters and protocol
This command message is used to set the protocol(SiRF Binary, NMEA, or USER1) and/or the
communication parameters(baud, data bits, stop bits, parity). Generally,this command would be used to switch
the module back to SiRF Binary protocol mode where a more extensive command message set is available. For
example,to change navigation parameters. When a valid message is received,the parameters will be stored in
battery backed SRAM and then the receiver will restart using the saved parameters.
Format: $PSRF100,<protocol>,<baud>,<DataBits>,<StopBits>,<Parity>*CKSUM <CR><LF>
<protocol> 0=SiRF Binary, 1=NMEA, 4=USER1 <baud> 1200, 2400, 4800,
9600, 19200, 38400 <DataBits> 8,7. Note that SiRF protocol is only valid f8 Data bits
<StopBits> 0,1
<Parity> 0=None, 1=Odd, 2=Even
Example 1: Switch to SiRF Binary protocol at 9600,8,N,1
$PSRF100,0,9600,8,1,0*0C<CR><LF>
Example 2: Switch to User1 protocol at 38400,8,N,1
$PSRF100,4,38400,8,1,0*38<CR><LF>