P3 CAT Command Reference

Introduction

This document is derived from the Elecraft P3 Programmer’s Reference, Rev. A7 (March 8, 2016, firmware 01.59). It provides a complete reference for the CAT (Computer Aided Transceiver) serial commands supported by the Elecraft P3 panadapter. These commands allow remote control of the P3’s most important instrument functions via its RS232 PC port.

The P3 Utility computer program provides a convenient Command Tester screen for trying individual commands, as well as macro support for sending strings of P3 and/or K3 commands with a single click. The Capture Image screen uses the #BMP command to upload the current P3 screen to a standard bitmap file.

When a K3 is connected to the RS232 XCVR port, both K3 and P3 commands can be sent from the same computer program. For example, #RVM; returns the P3 firmware revision while RVM; (without the # prefix) returns the K3 main firmware revision. This is a useful connectivity check: a response to #RVM; confirms the PC port is connected; a response to RVM; confirms the XCVR port is also connected.

Command Set Overview

The table below lists all P3 control commands. Commands marked “Internal use only” are omitted from the detailed reference.

Command	Description	Command	Description	Command	Description
=	Product ID	#LBL	Labels on/off	#RVS	SVGA firmware revision
#AVG	Averaging time	#MFA	Marker A frequency	#SCL	Scale
#BMP	Bitmap upload	#MFB	Marker B frequency	#SPM	Span mode
BR	Baud rate set	#MKA	Marker A on/off	#SPN	Span
#BR	Baud rate set	#MKB	Marker B on/off	#SVDT	SVGA data on/off
#CTF	Center frequency	#NB	Noise blanker on/off	#SVEN	SVGA enable
#DSM	Display mode	#NBL	Noise blanker level	#SVFL	SVGA fill on/off
#FNL	Function key label	#PKM	Peak mode on/off	#SVFN	SVGA font
#FNX	Function key execute	#PS	Power status/control	#SVRS	SVGA resolution
#FON	Display font size	#PT	Pass-through mode	#SVWB	SVGA waterfall bias
#FXA	Fixed auto-adjust mode	#QSY	QSY to current marker	#VFB	VFO B cursor on/off
#FXT	Fixed or tracking select	#RCF	Relative center freq.	#WFA	Waterfall average on/off
		#REF	Reference level	#WFC	Waterfall color
		#RST	Reset the P3	#WFM	Waterfall markers on/off
		#RVF	SVGA FPGA revision	#XCV	Transceiver select
		#RVM	Main firmware revision

Command Format

Commands sent from the computer to the P3 follow a GET/SET/RSP model:

• GET commands are sent by the computer to request information from the P3. The P3 responds with a RSP (response) message.
• SET commands are sent by the computer to change the P3’s configuration or initiate an event.
• Commands with an incorrect format or out-of-range parameter are silently ignored.
• A SET can be followed by a GET to verify the new settings.

SET Command Structure

SET commands use 2-4 characters, optional data fields, and a terminating semicolon (;).

#AVG05;      Set averaging on with time constant of 5
#DSM1;       Select spectrum+waterfall display mode

GET Command Structure

Many SET commands have a corresponding GET command, which is the command letters with no data, plus the semicolon. The RSP data format is usually identical to the SET data format; exceptions are noted in the individual command descriptions.

#AVG;         Get the current averaging setting
#DSM;         Get the current display mode

General Notes

• Characters sent to the P3 can be in either upper or lower case. The P3 always responds in upper case.
• All commands must be terminated with a semicolon (;) except where noted.
• When a K3 is connected to the XCVR port, commands without the # prefix are passed through to the K3.

Command Reference

This section describes all P3 GET, SET, and RSP command formats. Unless otherwise noted, the GET format is the command letters followed by a semicolon with no data. The SET and RSP data formats are identical unless otherwise noted.

= — Product Identification

Type: GET only

GET format:

=

RSP format:

P3        Main firmware executing
p3        Boot loader ready to download new firmware

There is no # prefix or semicolon in either the query or the response.

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#AVG — Averaging Time

Type: GET/SET

SET/RSP format:

#AVGnn;

Parameter	Values	Description
nn	00	Average mode off
nn	02-20	Averaging time constant (average mode on)

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#BMP — Bitmap Upload

Type: GET only

RSP format:

[bmp]cc

Field	Description
[bmp]	131,638 bytes of binary image data in standard .BMP file format
cc	Two-byte checksum

Notes:

• The response does not include the command name and has no terminating semicolon.
• The checksum is the modulo-65,536 sum of all 131,638 bytes, sent least-significant byte first.

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BR and #BR — Baud Rate

Type: SET only

SET format:

BRn;
#BRn;

Parameter	Value	Baud Rate
n	0	4800 baud
n	1	9600 baud
n	2	19200 baud
n	3	38400 baud

Notes:

• The P3 Utility program automatically sets the P3 to 38400 baud for downloads, then restores the user’s previous selection.
• The baud rate can also be set via the P3’s RS232 menu.
• The RS232 port that connects to the K3 always runs at 38400 baud.
• Any BR command received from a host computer affects the baud rate of the P3’s PC-facing RS232 port, not the K3.

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#CTF — Center Frequency

Type: GET/SET

SET/RSP format:

#CTFsxxxxxxxxxxx;

Parameter	Description
s	Sign: +, -, or space (space is equivalent to +)
xxxxxxxxxxx	Center frequency in Hz (11 digits)

Example:

#CTF+00014060000;     Set center frequency to 14,060 kHz

Notes:

• If the specified frequency is in a different band than the K3 is tuned to, the action is undefined.
• A value of zero sets the center frequency to the main VFO frequency of the transceiver.
• For transceivers other than the K3, the center frequency is interpreted relative to the frequency the transceiver is tuned to and may be positive or negative.

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#DSM — Display Mode

Type: GET/SET

SET/RSP format:

#DSMn;

Parameter	Value	Mode
n	0	Spectrum only
n	1	Spectrum + waterfall
n	2	Spectrum + power meters
n	3	Spectrum + waterfall + power meters

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#FNL — Function Key Label

Type: GET only

GET format:

#FNLn;

RSP format:

#FNLnccccccccc;

Parameter	Description
n	Key number, 1-8 (for keys FN1-FN8)
ccccccccc	9 ASCII characters of the key label for FNn

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#FON — Font Size

Type: GET/SET

SET/RSP format:

#FONn;

Parameter	Value	Font Size
n	0	5 x 7 pixels
n	1	7 x 11 pixels
n	2	9 x 14 pixels

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#FNX — Function Key Execute

Type: SET only

SET format:

#FNXn;

Parameter	Description
n	Key number, 1-8 (for keys FN1-FN8)

Executes the function assigned to the specified key, if any.

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#FXA — Fixed-tune Auto-adjust Mode

Type: GET/SET

SET/RSP format:

#FXAn;

Parameter	Value	Mode
n	0	Full screen
n	1	Half screen
n	2	Slide
n	3	Static

Specifies how far the P3 center frequency moves when the K3 VFO A is tuned off screen in fixed-tune mode.

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#FXT — Fixed or Tracking Select

Type: GET/SET

SET/RSP format:

#FXTn;

Parameter	Value	Mode
n	0	Tracking mode
n	1	Fixed-tune mode

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#LBL — Labels On/Off

Type: GET/SET

SET/RSP format:

#LBLn;

Parameter	Value	Description
n	0	FN key labels off
n	1	FN key labels on

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#MFA and #MFB — Marker A/B Frequency

Type: GET/SET

SET/RSP format:

#MFAsxxxxxxxxxxx;
#MFBsxxxxxxxxxxx;

Parameter	Description
s	Sign: +, -, or space (space is equivalent to +)
xxxxxxxxxxx	Marker frequency in Hz (11 digits)

Example:

#MFA+00014060000;     Set marker A frequency to 14,060 kHz

Notes:

• If the specified frequency is in a different band than the K3 is tuned to, the action is undefined.
• A value of zero sets the marker to the main VFO frequency of the transceiver.
• For transceivers other than the K3, the marker frequency is interpreted relative to the frequency the transceiver is tuned to and may be positive or negative.

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#MKA and #MKB — Marker A/B On/Off

Type: GET/SET

SET/RSP format:

#MKAn;
#MKBn;

Parameter	Value	Description
n	0	Marker off
n	1	Marker on

Notes:

• The last marker to be turned on automatically becomes the active marker, meaning it can be adjusted with the knob and responds to the QSY command.
• If the marker was off-screen before executing a marker-on command, it will default to the center frequency.

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#NB — Noise Blanker On/Off

Type: GET/SET

SET/RSP format:

#NBn;

Parameter	Value	Description
n	0	Noise blanker off
n	1	Noise blanker on

---

#NBL — Noise Blanker Level

Type: GET/SET

SET/RSP format:

#NBLnn;

Parameter	Values	Description
nn	1-15	Noise blanker aggressiveness (1 = least, 15 = most)

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#PKM — Peak Mode On/Off

Type: GET/SET

SET/RSP format:

#PKMn;

Parameter	Value	Description
n	0	Peak mode off
n	1	Peak mode on

---

#PS — Power Status

Type: GET/SET

SET/RSP format:

#PSn;

Parameter	Value	Description
n	0	Turn P3 off
n	1	P3 is on

Notes:

• #PS0 turns the P3 off, but this removes power, so #PS1 cannot be used to turn it back on.
• If the power-on jumper on the rear-panel I/O board is in the “always on” position, the #PS0 command has no effect.

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#PT — Pass-Through Mode

Type: SET only

SET format:

#PT;

Sets the P3 to pass-through mode: panadapter operation ceases and all data received on either RS232 port is passed through immediately to the other RS232 port without delay or modification.

Notes:

• This command is used by P3 Utility when downloading new firmware to the K3 transceiver.
• Pass-through mode ends automatically 8 seconds after the last RS232 activity.

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#QSY — QSY to Current Marker

Type: SET only

SET format:

#QSYn;

Parameter	Value	Description
n	0	Undo QSY (return VFO to pre-QSY frequency; one-level undo)
n	1	QSY (transfer active marker frequency to associated VFO)

Notes:

• Marker A controls VFO A; Marker B controls VFO B.
• “Undo QSY” returns the VFO to the frequency it was on before the last QSY (one-level undo).

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#RCF — Relative Center Frequency

Type: GET/SET

SET format:

#RCFsnnnnnn;

Parameter	Description
s	Sign: + or -
nnnnnn	Offset in Hz (6 digits)

The offset is added to the VFO A frequency to compute the new center frequency. This command is used to position the VFO A cursor on the screen.

Example:

#RCF+025000;     With a 50 kHz span, moves VFO A cursor to the left edge

The center frequency moves up 25 kHz, which shifts the VFO A cursor to the left.

RSP format:

#RCFsnnnnnn;

The response returns the difference between the current center frequency and the VFO A frequency.

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#REF — Reference Level

Type: GET/SET

SET/RSP format:

#REFsnnn;

Parameter	Description
s	Sign: +, -, or space (space is equivalent to +)
nnn	Reference level in dBm, range -170 to +010

Example:

#REF-120;     Set reference level (bottom of spectrum screen) to -120 dBm

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#RST — Reset the P3

Type: SET only

SET format:

#RST;

Forces a power-on reset of the P3.

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#RVF — SVGA FPGA Image Revision

Type: GET only

GET format:

#RVFnn;

RSP format:

#RVFnnNN.NN;

Parameter	Description
nn	FPGA image number, 00 to 05
NN.NN	Image revision (e.g., 01.23)

Notes:

• Returns 99.99 if no FPGA image is installed.

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#RVM — Main Firmware Revision

Type: GET only

RSP format:

#RVMNN.NN;

Parameter	Description
NN.NN	Firmware revision (e.g., 01.23)

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#RVS — SVGA Board Firmware Revision

Type: GET only

RSP format:

#RVSNN.NN;

Parameter	Description
NN.NN	Firmware revision (e.g., 01.23)

Notes:

• Returns 99.99 if no SVGA firmware is installed.
• Returns 00.00 if only the SVGA boot loader is installed.

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#SCL — Scale

Type: GET/SET

SET/RSP format:

#SCLnnn;

Parameter	Values	Description
nnn	010-080	Scale in dB (difference between top and bottom of spectrum screen)

Example:

#SCL080;     Set scale to 80 dB

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#SPM — Span Mode

Type: GET/SET

SET/RSP format:

#SPMn;

Parameter	Value	Mode
n	0	Continuous span mode
n	1	Stepped span mode

Notes:

• In stepped span mode, the span steps between 2, 5, 10, 20, 50, 100, and 200 kHz.

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#SPN — Span

Type: GET/SET

SET/RSP format:

#SPNxxxxxx;

Parameter	Values	Description
xxxxxx	000020-002000	Span in 100 Hz units

Example:

#SPN000500;     Set span to 50 kHz (500 x 100 Hz)

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#SVDT — SVGA Decoded Data Display On/Off

Type: GET/SET

SET/RSP format:

#SVDTn;

Parameter	Value	Description
n	0	Data display off
n	1	Data display on

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#SVEN — SVGA Display On/Off

Type: GET/SET

SET/RSP format:

#SVENn;

Parameter	Value	Description
n	0	SVGA display off
n	1	SVGA display on

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#SVFL — SVGA Spectrum Fill On/Off

Type: GET/SET

SET/RSP format:

#SVFLn;

Parameter	Value	Description
n	0	Fill off
n	1	Fill on

Notes:

• When on, the area below the spectrum trace on the external SVGA display is filled in for easier visibility.

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#SVFN — SVGA Font Select

Type: GET/SET

SET/RSP format:

#SVFNn;

Parameter	Values	Description
n	0-3	Font number (larger number = larger font)

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#SVRS — SVGA Display Resolution

Type: GET/SET

SET/RSP format:

#SVRSn;

Parameter	Values	Description
n	0-4	External display resolution

See the SVGA option manual for details on resolution values.

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#SVWB — SVGA Waterfall Bias

Type: GET/SET

SET/RSP format:

#SVWBnn;

Parameter	Values	Description
nn	01-99	Waterfall bias, corresponding to 0.1-9.9 in the P3 “SVGA bias” menu

Notes:

• The higher the number, the greater the color contrast in the external display waterfall.
• A value of 1.0 (parameter 10) makes the display look similar to the P3 screen on a typical monitor.

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#VFB — VFO B Cursor On/Off

Type: GET/SET

SET/RSP format:

#VFBn;

Parameter	Value	Description
n	0	VFO B cursor off
n	1	VFO B cursor on

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#WFA — Waterfall Averaging On/Off

Type: GET/SET

SET/RSP format:

#WFAn;

Parameter	Value	Description
n	0	Waterfall averaging off
n	1	Waterfall averaging on

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#WFC — Waterfall Color

Type: GET/SET

SET/RSP format:

#WFCn;

Parameter	Value	Description
n	0	Gray scale waterfall
n	1	Colored waterfall

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#WFM — Waterfall Markers On/Off

Type: GET/SET

SET/RSP format:

#WFMn;

Parameter	Value	Description
n	0	Waterfall markers off
n	1	Waterfall markers on

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#XCV — Transceiver Select

Type: GET/SET

SET/RSP format:

#XCVnn;

Parameter	Value	Description
nn	00	K3
nn	01	User-defined transceiver
nn	02	455 kHz IF
nn	03+	Additional transceivers per “Xcvr Sel” menu

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Appendix A: Change History

Applicable firmware revision shown in brackets.

Revision	Date	Firmware	Changes
A1	2010-10-20	00.41	Added commands #AVG, #CTF, #DPM, #FNL, #FNX, #LBL, #MFA/#MFB, #MKA/#MKB, #PKM, #PS, #QSY, #REF, #SCL, and #SPN.
A2	2010-11-05	00.41	Added “Internal use only” commands to the table. Changed #DPM command name to #DSM. Changed #SPN format. Added #PT and #VFB commands.
A3	2011-02-16	01.05	Added commands #FXA, #FXT, and #TP.
A4	2012-03-19	01.11	Added commands #RST, #RVF, and #RVS.
A5	2015-01-23	01.35	Added commands #NB, #NBL, #SPM, #SVWB, #SVDT, #SVEN, #SVFN, #SVFL, #SVRS, #WFA, #WFC, and #WFM.
A6	2016-02-02	01.57	Changed #DSM command. Added #FON and #XCV commands.
A7	2016-03-08	01.59	Added #RCF command.