SCOUT PRO Protocol

SCOUT PRO exposes standard NMEA 0183 output, RTCM v3.x correction input, and PAIR proprietary commands for receiver configuration. Use this reference to review the PAIR packet structure, query receiver status, adjust GNSS behavior, and configure serial output.

Protocol scope

NMEA 0183 output Standard positioning sentences for host applications and integration workflows.

RTCM v3.x input Correction-data input for RTK positioning workflows.

PAIR configuration commands Proprietary query and set commands for receiver-level configuration.

1. PAIR command packet structure

All Kalmix GUIDE K35-series proprietary commands and responses follow the same string format. The maximum length of a command packet is 255 bytes.

$PAIR<Command_ID>[,<Data_Field_1>,...,<Data_Field_N>]*<Checksum><CR><LF>

$PAIR: Proprietary command header.
<Command_ID>: Three-digit numeric command identifier, such as 050.
<Data_Field>: Command-specific parameters separated by commas.
*<Checksum>: 8-bit XOR checksum of all characters between $ and *.
<CR><LF>: Packet terminator in hexadecimal format: 0D 0A.

Persistence note

Configuration changes are not automatically stored across power cycles. Send $PAIR513 after changing persistent settings, then reboot the receiver or cycle the power supply.

2. PAIR command quick reference

Command	Type	Category	Function description
System status & control
`PAIR001`	Output	Command acknowledgement	Return the PAIR command execution result.
`PAIR020`	Query	Get version	Query firmware release information.
`PAIR024`	Query	Get chip version	Query the GNSS chipset version.
`PAIR004`	Set	Hot start	Restart using available navigation data stored in NVRAM.
`PAIR005`	Set	Warm start	Restart without using stored ephemeris data.
`PAIR006`	Set	Cold start	Restart without using stored navigation data.
`PAIR023`	Set	System reboot	Reboot the GNSS chipset immediately.
`PAIR513`	Set	Save settings	Store the current configuration in NVRAM.
`PAIR514`	Set	Restore settings	Clear NVRAM and restore factory defaults.
GNSS configuration
`PAIR066`	Set	Set search mode	Enable or disable satellite constellations.
`PAIR067`	Query	Get search mode	Query the current constellation settings.
`PAIR050`	Set	Set fix interval	Set the navigation update interval, such as 1 Hz or 10 Hz.
`PAIR051`	Query	Get fix interval	Query the current navigation update interval.
`PAIR031`	Query	Get 3D velocity	Query the WGS84 ECEF XYZ Cartesian velocity vector.
Interface & formatting
`PAIR864`	Set	Set baud rate	Configure the UART baud rate.
`PAIR865`	Query	Get baud rate	Query the current UART baud rate.
`PAIR062`	Set	Set NMEA rate	Configure the output interval for a selected NMEA sentence.
`PAIR063`	Query	Get NMEA rate	Query the output interval for a selected NMEA sentence.
`PAIR098`	Set	Set precision	Configure fractional precision for NMEA position values.
`PAIR099`	Query	Get precision	Query the current NMEA decimal precision mode.
`PAIR100`	Set	Set NMEA output mode	Configure the NMEA protocol output mode.
`PAIR101`	Query	Get NMEA output mode	Query the current NMEA protocol output mode.

3. Detailed PAIR command dictionary

3.1 System status & control

$PAIR001 - Command acknowledgement

Description

Return the PAIR command execution result.

Type

Output

Return format

$PAIR001,<Command_ID>,<Result>*<Checksum><CR><LF>

Return parameters

Field	Description
`Command_ID`	The three-digit command ID being acknowledged.
`Result`	0: Command successfully sent. 1: Command is processing; wait for the result. 2: Command sending failed. 3: Command ID is not supported. 4: Command parameter error, including out-of-range, missing, or checksum errors. 5: MNL service is busy; retry shortly.

Example

// Host send: cold start
$PAIR006*3C

// Receiver response: success acknowledgement
$PAIR001,006,0*3D

$PAIR020 - Get version

Description

Query firmware release information, hardware and software configuration, and subsystem versions.

Type

Query

Format

$PAIR020*CS<CR><LF>

Return format

The receiver returns a standard acknowledgement packet followed by the detailed version information.

$PAIR020,<Project_Version>,<Frequency>,<SW_package>,<Service_version>,<Service_build_time>,
  <DSP_L1_rom_version>,<DSP_L1_ram_version>,<DSP_L5_rom_version>,<DSP_L5_ram_version>,
  <Kernel_version>,<Kernel_build_time>,<KF_version>,<KF_build_time>,<RTK_version>,
  <RTK_build_time>,<Fusion_version>,<Fusion_build_time>*<Checksum><CR><LF>

Return parameters

Field	Description
`Project_Version`	Format: `<Project_board>_<SDK_version>_<SDK_Build_time>` Example: `AG3335A_V1.0.0_20190729`
`Frequency`	S: Single frequency D: Dual frequency
`SW_package`	N: Normal W: RAW R: RTK I: NavIC F: Fusion
`Service_version`	MNL service version, seven characters.
`Subsystem versions`	DSP L1 and L5, Kernel, KF, RTK, and Fusion version values. Each version is followed by its build time in `yyMMDDhhmm` format.

Example

// Host send
$PAIR020*38

// Receiver response
$PAIR001,020,0*39
$PAIR020,AG3335A_V1.0.0_YYYYMMDD,D,N,xxxxxxx,yyMMDDhhmm,xx.xxx,xx.xxx,xxxxxxx,yyMMDDhhmm,xxxxxxx,yyMMDDhhmm,xxxxxxx,yyMMDDhhmm,xxxxxxx,yyMMDDhhmm*40

$PAIR024 - Get chip version

Description

Query the chipset version.

Type

Query

Format

$PAIR024*3C<CR><LF>

Return format

$PAIR024,<CHIP>*<Checksum><CR><LF>

Return parameters

Field	Description
`CHIP`	Chipset version, such as `A`, `M`, or `S`.

Example

// Host send
$PAIR024*3C

// Receiver response
$PAIR001,024,0*3D
$PAIR024,M*5D

$PAIR004 - Hot start

Description

Restart the receiver using available navigation data stored in NVRAM.

Type

Set

Format

$PAIR004*3E<CR><LF>

Return format

$PAIR001,004,<Result>*<Checksum><CR><LF>

Example

// Host send
$PAIR004*3E

// Receiver response
$PAIR001,004,0*3F

$PAIR005 - Warm start

Description

Restart the receiver without using stored ephemeris data.

Type

Set

Format

$PAIR005*3F<CR><LF>

Return format

$PAIR001,005,<Result>*<Checksum><CR><LF>

Example

// Host send
$PAIR005*3F

// Receiver response
$PAIR001,005,0*3E

$PAIR006 - Cold start

Description

Restart the receiver without using stored position, almanac, or ephemeris data.

Type

Set

Format

$PAIR006*3C<CR><LF>

Return format

$PAIR001,006,<Result>*<Checksum><CR><LF>

Example

// Host send
$PAIR006*3C

// Receiver response
$PAIR001,006,0*3D

$PAIR023 - System reboot

Description

Reboot the GNSS chipset immediately.

Type

Set

Format

$PAIR023*3B<CR><LF>

Return format

None. The receiver reboots immediately without sending a response.

Example

// Host send
$PAIR023*3B

$PAIR513 - Save settings to NVRAM

Description

Save the current configuration to flash or NVRAM so that changes persist across power cycles.

Type

Set

Format

$PAIR513*3D<CR><LF>

Return format

$PAIR001,513,<Result>*<Checksum><CR><LF>

Example

// Host send
$PAIR513*3D

// Receiver response
$PAIR001,513,0*3C

$PAIR514 - Restore factory defaults

Description

Clear the current user configuration and restore factory defaults.

Type

Set

Format

$PAIR514*3A<CR><LF>

Return format

$PAIR001,514,<Result>*<Checksum><CR><LF>

Example

// Host send
$PAIR514*3A

// Receiver response
$PAIR001,514,0*3B

3.2 GNSS configuration

$PAIR066 - Set GNSS search mode

Description

Enable or disable satellite constellations. The receiver restarts when it receives this command.

Type

Set

Format

$PAIR066,<GPS>,<GLO>,<GAL>,<BDS>,<QZSS>,<NavIC>*<Checksum><CR><LF>

Parameters

Field	Description
`Constellation flags`	0: Disable 1: Enable

Return format

$PAIR001,066,<Result>*<Checksum><CR><LF>

Example

// Host send: enable GPS, GLONASS, Galileo, BeiDou, and QZSS; disable NavIC
$PAIR066,1,1,1,1,1,0*3B

// Receiver response
$PAIR001,066,0*3B

$PAIR067 - Get GNSS search mode

Description

Query GPS, GLONASS, Galileo, BeiDou, QZSS, and NavIC constellation settings.

Type

Query

Format

$PAIR067*3B<CR><LF>

Return format

$PAIR067,<GPS>,<GLO>,<GAL>,<BDS>,<QZSS>,<NavIC>*<Checksum><CR><LF>

Return parameters

Field	Description
`Constellation flags`	0: Disabled 1: Enabled

Example

// Host send
$PAIR067*3B

// Receiver response
$PAIR001,067,0*3A
$PAIR067,1,0,0,0,0,0*3A

$PAIR050 - Set position fix interval

Description

Set the navigation update interval. When the interval is below 1000 ms, the ASCII NMEA output interval may increase automatically.

Type

Set

Format

$PAIR050,<Interval_ms>*<Checksum><CR><LF>

Parameters

Field	Description
`Interval_ms`	Position fix interval in milliseconds. Valid range: `100` to `1000`. 1000: 1 Hz, default 200: 5 Hz 100: 10 Hz

Return format

$PAIR001,050,<Result>*<Checksum><CR><LF>

Example

// Host send: set 10 Hz
$PAIR050,100*22

// Receiver response
$PAIR001,050,0*3E

$PAIR051 - Get position fix interval

Description

Query the current position fix interval.

Type

Query

Format

$PAIR051*3E<CR><LF>

Return format

$PAIR051,<Interval_ms>*<Checksum><CR><LF>

Return parameters

Field	Description
`Interval_ms`	Position fix interval in milliseconds.

Example

// Host send
$PAIR051*3E

// Receiver response
$PAIR001,051,0*3F
$PAIR051,1000*13

$PAIR031 - Get 3D velocity

Description

Query the WGS84 ECEF XYZ Cartesian velocity vector in meters per second, with an estimated 1-sigma accuracy.

Type

Query

Format

$PAIR031*38<CR><LF>

Return format

$PAIR031,<VX>,<VY>,<VZ>,<Acc>*<Checksum><CR><LF>

Return parameters

Field	Description
`VX`	WGS84 ECEF X Cartesian velocity vector in m/s.
`VY`	WGS84 ECEF Y Cartesian velocity vector in m/s.
`VZ`	WGS84 ECEF Z Cartesian velocity vector in m/s.
`Acc`	Three-dimensional speed 1-sigma accuracy in m/s.

Example

// Host send
$PAIR031*38

// Receiver response
$PAIR001,031,0*39
$PAIR031,0.19,-0.07,-0.11,0.49*3A

3.3 Interface & formatting

$PAIR864 - Set baud rate

Description

Set the UART baud rate of the GNSS module.

Type

Set

Baud-rate change

The baud-rate change takes effect immediately after the next response. To keep the change after a power cycle, send $PAIR513 to save the settings, then reboot with $PAIR023 or cycle the power supply.

Format

$PAIR864,<Port_Type>,<Port_Index>,<Baudrate>*<Checksum><CR><LF>

Parameters

Field	Description
`Port_Type`	0: UART
`Port_Index`	0: UART0, main communication port
`Baudrate`	`9600`, `115200` default, `230400`, `460800`, or `921600`.

Return format

$PAIR001,864,<Result>*<Checksum><CR><LF>

Example

// Host send: set UART0 baud rate to 115200
$PAIR864,0,0,115200*1B

// Receiver response: sent at the current baud rate before changing
$PAIR001,864,0*31

$PAIR865 - Get baud rate

Description

Query the UART baud rate of the GNSS module.

Type

Query

Format

$PAIR865,<Port_Type>,<Port_Index>*<Checksum><CR><LF>

Parameters

Field	Description
`Port_Type`	0: UART
`Port_Index`	0: UART0, main communication port

Return format

$PAIR865,<Port_Type>,<Port_Index>,<Baudrate>*<Checksum><CR><LF>

Return parameters

Field	Description
`Baudrate`	Current UART baud rate.

Example

// Host send
$PAIR865,0,0*37

// Receiver response
$PAIR001,865,0*30
$PAIR865,0,0,115200*1A

$PAIR062 - Set NMEA output rate

Description

Configure the output interval of a selected NMEA sentence.

Type

Set

Format

$PAIR062,<Type>,<Output_Rate>*<Checksum><CR><LF>

Parameters

Field	Description
`Type`	-1: Reset all sentences to default 0: NMEA_SEN_GGA 1: NMEA_SEN_GLL 2: NMEA_SEN_GSA 3: NMEA_SEN_GSV 4: NMEA_SEN_RMC 5: NMEA_SEN_VTG 6: NMEA_SEN_ZDA 7: NMEA_SEN_GRS 8: NMEA_SEN_GST
`Output_Rate`	0: Disabled; do not output the sentence. 1: Output once every position fix. 2: Output once every two position fixes. Valid range: `0` to `20`.

Return format

$PAIR001,062,<Result>*<Checksum><CR><LF>

Example

// Host send: disable GSV output
$PAIR062,3,0*3F

// Receiver response
$PAIR001,062,0*3F

$PAIR063 - Get NMEA output rate

Description

Query the output interval of a selected NMEA sentence.

Type

Query

Format

$PAIR063,<Type>*<Checksum><CR><LF>

Parameters

Field	Description
`Type`	NMEA sentence type. Use `-1` to return all configurations or `0` to `8` for a selected sentence.

Return format

$PAIR063,<Type>,<Output_Rate>*<Checksum><CR><LF>

Return parameters

Field	Description
`Output_Rate`	Current output interval setting from `0` to `20`.

Example

// Host send
$PAIR063,0*23

// Receiver response
$PAIR001,063,0*3E
$PAIR063,0,3*3C

$PAIR098 - Set NMEA decimal precision

Description

Configure the number of decimal digits shown in NMEA position values.

Type

Set

Format

$PAIR098,<MODE>*<Checksum><CR><LF>

Parameters

Field	Description
`MODE`	0: Latitude and longitude with four digits; altitude with one digit. 1: Latitude and longitude with five digits; altitude with two digits. 2: Latitude and longitude with six digits; altitude with three digits. 3: Latitude and longitude with seven digits; altitude with three digits.

Return format

$PAIR001,098,<Result>*<Checksum><CR><LF>

Example

// Host send
$PAIR098,0*27

// Receiver response
$PAIR001,098,0*3A

$PAIR099 - Get NMEA decimal precision

Description

Query the current NMEA position precision mode.

Type

Query

Format

$PAIR099*3A<CR><LF>

Return format

$PAIR099,<MODE>*<Checksum><CR><LF>

Return parameters

Field	Description
`MODE`	Current precision mode from `0` to `3`.

Example

// Host send
$PAIR099*3A

// Receiver response
$PAIR001,099,0*3B
$PAIR099,0*26

$PAIR100 - Set NMEA output mode

Description

Configure the NMEA output mode.

Type

Set

Format

$PAIR100,<NMEA_MODE>,<PROPRIETARY_MODE>*<Checksum><CR><LF>

Parameters

Field	Description
`NMEA_MODE`	0: Disable NMEA. 1: ASCII NMEA v4.1, default. 2: ASCII NMEA v3.0.
`PROPRIETARY_MODE`	0: Disable additional proprietary sentences, default. 1: Enable proprietary sentences.

Return format

$PAIR001,100,<Result>*<Checksum><CR><LF>

Example

// Host send: ASCII NMEA v4.1, additional proprietary sentence disabled
$PAIR100,1,0*3A

// Receiver response
$PAIR001,100,0*3A

$PAIR101 - Get NMEA output mode

Description

Query the current NMEA output mode.

Type

Query

Format

$PAIR101*3A<CR><LF>

Return format

$PAIR101,<NMEA_MODE>,<PROPRIETARY_MODE>*<Checksum><CR><LF>

Return parameters

Field	Description
`NMEA_MODE`	Current standard NMEA output mode from `0` to `2`.
`PROPRIETARY_MODE`	Current proprietary sentence output state from `0` to `1`.

Example

// Host send
$PAIR101*3A

// Receiver response
$PAIR001,101,0*3B
$PAIR101,0,1*3B

Integration references

Continue with the product specifications or the shared integration documentation for host setup and evaluation workflows.

Specifications Review GNSS performance, electrical limits, and supported interfaces. Get Started Follow the shared evaluation and integration paths for SCOUT Series. Tools & Utilities Access available drivers, drawings, and configuration resources.

Product evaluation

Evaluating SCOUT PRO for your machine?

Review the product page or discuss an integration requirement with the Kalmix team.

View SCOUT PRO Discuss Integration