background image

–     –

–     –

18

19

100 – SetSerialPort

This command message is used to set the protocol (SiRF binary or NMEA)
and/or the communication parameters (baud rate). Generally, this 
command is used to switch the module back to SiRF binary protocol mode 
where a more extensive command message set is available. When a valid 
message is received, the parameters are stored in battery-backed SRAM 
and the receiver restarts using the saved parameters.

Figure 18 contains the values for the following example:
Switch to SiRF binary protocol at 9600,8,N,1

$PSRF100,0,9600,8,1,0*0C

For details on the SiRF binary protocol, please refer to SiRF’s Binary 
Protocol Reference Manual.

SetSerialPort Example

Name

Example

Description

Message ID

$PSRF100

PSRF100 protocol header

Protocol

0

0=SiRF binary, 1=NMEA

Baud

9600

4800, 9600, 19200, 38400, 57600, 115200

DataBits

8

8

1

StopBits

1

0, 1

1

Parity

0

0=None, 1=Odd, 2=Even

1

Checksum

*0C

<CR> <LF>

End of message termination

1.  SiRF protocol is only valid for 8 data bits, 1 stop bit and no parity.
2.  Default settings are NMEA protocol using 9,600 baud, 8 data bits, 2 stop bits and no 

parity.

Figure 18: SetSerialPort Example

101 – NavigationInitialization

This command is used to initialize the receiver with the current position (in 
X, Y, Z coordinates), clock offset, and time, enabling a faster fix. Increased 
receiver sensitivity and the removal of Selective Availability (SA) have made 
this unneccessary. The command is retained for its ability to reset the 
module, but the initialization fields are no longer supported.

Figure 19 contains the values for the following example:

$PSRF101,-2686700,-4304200,3851624,96000,497260,921,12,3*1C

Figure 19: NavigationInitialization Example

NavigationInitialization Example

Name

Example

Units

Description

Message ID

$PSRF101

PSRF101 protocol header

ECEF X

-2686700

meters

X coordinate position

ECEF Y

-4304200

meters

Y coordinate position

ECEF Z

3851624

meters

Z coordinate position

ClkOffset

96000

Hz

Clock Offset

1

TimeOfWeek

497260

seconds

GPS Time Of Week

WeekNo

921

GPS Week Number

ChannelCount

12

Range 1 to 12

ResetCfg

3

See Figure 20

Checksum

*1F

<CR> <LF>

End of message termination

1.  Use 0 for the last saved value if available. If this is unavailable, a default value of 

96000 is used.

ResetCfg Values

Hex

Description

0x01

Hot Start – All data valid

0x02

Warm Start – Ephemeris cleared

0x04

Cold Start – Clears all data in memory

0x08

Clear Memory – Clears all data in memory and resets the receiver 

back to factory defaults

Figure 20: ResetCfg Values

Summary of Contents for R4 Series

Page 1: ...R4 Series GPS Receiver Module Data Guide...

Page 2: ...egulatory certification and warranty Customers may use our non Function Modules Antenna and Connectors as part of other systems in Life Safety Situations but only with necessary and industry appropria...

Page 3: ...us RF or GPS experience Features SiRF Star IV chipset Built in jammer remover High sensitivity 160dBm 48 channels Fast TTFF at low signal levels Battery backed SRAM CGEE allows 3 day prediction No pro...

Page 4: ...Supply Operating Voltage VCC 3 0 3 3 3 6 VDC Supply Current lCC Peak 122 mA 1 Acquisition 56 mA 1 Tracking 33 mA 1 Hibernate 0 43 mA 1 Backup Battery Voltage VBAT 2 0 6 0 VDC Backup Battery Current IB...

Page 5: ...satellite transmits low power radio signals which contain three different bits of information a pseudorandom code identifying the satellite ephemeris data which contains the current date and time as...

Page 6: ...then outputs the data through a standard serial port using several standard NMEA protocol formats The GPS core handles all of the necessary initialization tracking and calculations autonomously so no...

Page 7: ...RFIN line This bead prevents the RF from getting into the power supply but allows the DC voltage onto the RF trace to feed into the antenna A series capacitor inside the module prevents this DC volta...

Page 8: ...have selectable baud rates it s recommended that SiRF Binary use 115 200bps For a detailed description of the SiRF Binary protocol see the SiRF Binary Protocol Reference Manual available from SiRF Tec...

Page 9: ...rential GPS SPS Mode fix valid 3 5 Not supported 6 Dead Reckoning Mode fix valid Figure 9 Position Indicator Values GLL Geographic Position Latitude Longitude Figure 10 contains the values for the fol...

Page 10: ...s Channel 4 Range 00 to 90 Azimuth 077 degrees Channel 4 Range 00 to 359 SNR C No 46 dB Hz Channel 4 Range 00 to 99 null when not tracking Checksum 73 CR LF End of message termination 1 Depending on t...

Page 11: ...Figure 17 outlines the message identifiers supported by the module Serial Data Structure Name Example Description Start Sequence PSRF Message ID MID Message Identifier consisting of three numeric cha...

Page 12: ...alization This command is used to initialize the receiver with the current position in X Y Z coordinates clock offset and time enabling a faster fix Increased receiver sensitivity and the removal of S...

Page 13: ...ssages may be polled once or setup for periodic output Checksums may also be enabled or disabled depending on the needs of the receiving program NMEA message settings are saved in battery backed memor...

Page 14: ...ault value of 96000 is used Figure 24 ResetCfg Values ResetCfg Values Hex Description 0x01 Hot Start All data valid 0x02 Warm Start Ephemeris cleared 0x04 Cold Start Clears all data in memory 0x08 Cle...

Page 15: ...e is also included for use with a PC running custom software or the included development software The Master Development System software enables configuration of the receiver and displays the satellit...

Page 16: ...r the module A ground plane as large and uninterrupted as possible should be placed on a lower layer of your PC board opposite the module This plane is essential for creating a low impedance return fo...

Page 17: ...ackage that supports hand and automated assembly techniques Since the modules contain discrete components internally the assembly procedures are critical to ensuring the reliable function of the modul...

Page 18: ...irreparably damage the modules Assembly personnel need to pay careful attention to the oven s profile to ensure that it meets the requirements necessary to successfully reflow all components while sti...

Page 19: ...stomer including without limitation breach of contract breach of warranty strict liability or negligence Customer assumes all liability including without limitation liability for injury to person or p...

Reviews: