GEMINI SYSTEM LEVEL 4 VERSION 1.0 SERIAL INTERFACE COMMAND DESCRIPTION

Gemini's LX200-like Commands

The Gemini system supports a subset of the Meade® LX200 Command Set making it compatible to many planetarium programs using this command set. Programs featuring special Gemini drivers can make use of the LX200 style extensions added as well as of the Gemini supports a Native Command Set described below. Many of these features and a hub functionality allowing several programs to access the Gemini controler simultaneously can be accessed by using an ASCOM driver .

Syntax: values in <> are (to be) replaced by actual values. Curled brackets {} show alternative characters.
Upon completion, ASCII characters or strings are returned, if indicated.
 

Command	Returns	Remarks
0x06 (ACK char)	B# while the initial startup message is being displayed (new in L4), b# while waiting for the selection of the Startup Mode, S# during a Cold Start (new in L4) or G# after completed startup.	Usable for testing the serial link and determining the type of mount (German equatorial). During Startup, with a "b#" being returned, the PC can select the startup mode by sending a bC# for selecting the Cold Start, bW# for selecting the Warm Start and bR# for selecting the Warm Restart.
Synchronize
:Cm#	No object!#  or <object name>#	The string "No object!#" is returned if the mount is not aligned or no object was selected, otherwise the name of the selected object used is returned. This command does an "Additional Alignment", (re)calculating the pointing model parameters and synchronizing to the position given.
:CM#	No object!#  or <object name>#	The string "No object!#" is returned if the mount is not aligned or no object was selected, otherwise the name of the selected object used is returned. The position (RA and DEC) is synchronized to the position of the object without affecting the modelling parameters.
Focus Control
:F+#		Focus In
:F-#		Focus Out
:FQ#		Stop focusing
:FF#		Focus Fast
:FM#		Focus Medium
:FS#		Focus Slow
Get Information
:GA#	In High Precision mode: {+-}<dd>:<mm>:<ss># In Low Precision mode: {+-}<dd>°<mm>#	Get Altitude (from L1, V2.0 up)
:GB#	<n>#	Get LED Display Brightness Value(from L1, V2.0 up) n=0: 100% n=6: 6.6% n=7: blank display n=8: test mode (all pixels lit).
:GC#	<mm>/<dd>/<yy>#	Local Calendar Date, month mm, days dd and years yy separated by slashes.
:Gc#	(24)#	Clock Format
:GD#	In High Precision mode: {+-}<dd>:<mm>:<ss># In Low Precision mode: {+-}<dd>°<mm>#	Apparent (refraction included) Declination the telescope is pointing to, to the equinox of the date. Except during GoTo operations, the coordinates are corrected according to the pointing model.  Signed degrees (-90 to +90), minutes, seconds. The degree sign in Low Precision mode is the character 0xDF.
:GE#	<hh>:<mm>:<ss>#	Get Alarm time (from L1, V2.0 up)
:GG#	{+-}<hh>#	Get the number of hours by which your local time differs from UTC (from L1, V2.0 up). If your local time is earlier than UTC this command will return a positive value, if later than UTC the value is negative.
:Gg#	{+-}<ddd>°<mm>#	Get Site Longitude (from L1, V2.0 up)
:GH#	[-]<hh>:<mm>:<ss>#	Hour Angle the telescope is pointing to. From L4, V1.0 up.
:GL#	<hh>:<mm>:<ss>#	Civil Time (UTC time from the internal Real Time Clock + UTC offset), hours, minutes, seconds in 24-hour format.
:Gm#	{EW}#	Get Telescope Mount's Side of Meridian. E# for East or W# for West side is replied. From L4, V1.0 up.
:GM#	<name string>#	Name (up to 15 characters) of the first site stored.
:GN#	<name string>#	Name (up to 15 characters) of the second site stored.
:GO#	<name string>#	Name (up to 15 characters) of the third site stored.
:GP#	<name string>#	Name (up to 15 characters) of the fourth site stored.
:GR#	High Precision mode: <hh>:<mm>:<ss># Low Precision mode: <hh>:<mm>.<m>#	Apparent (refraction included) Right Ascension the telescope is pointing to, to the equinox of the date. Despite during GoTo operations, the coordinates are corrected according to the pointing model.  Hours (0 to 24), minutes, seconds or tenth of minutes.
:GS#	<hh>:<mm>:<ss>#	Sidereal Time. From L4, V1.0 up.
:Gt#	{+-}<dd>°<mm>#	Get Site Latitude (from L1, V2.0 up).
:GV#	<l><vv>#	Get Software Level l(one digit) and Version vv(two digits)
:GVD#	<mm> <dd> <yyyy>#	Get Software Built Date (from L4, V1.0 up)
:GVN#	<l>.<vv>#	Get Software Level l(one digit) and Version vv(two digits) (from L4, V1.0 up)
:GVP#	Losmandy Gemini#	Product String (from L4, V1.0 up)
:GVT#	<hh>:<mm>:<ss>#	Get Software Built Time (from L4, V1.0 up)
:Gv#	N (for "no tracking") T (for Tracking) G (for Guiding) C (for Centering) S (for Slewing)	Get Velocity (from L1, V2.0 up)
:GZ#	In High Precision mode: <ddd>:<mm>:<ss># In Low Precision mode: <ddd>°<mm>#	Get Azimuth. From North over East. (From L4, V1.0 up)
Home Position
:hP#		Move to Home Position. The Home Position defaults to the celestial pole visible at the given hemisphere (north or south) but can be set by the user at the Gemini.
Startup Position
:hC#		Move to the Startup Position. This position is the position required for a Cold or Warm Start, pointing to the celestial pole of the given hemisphere (north or south), with the counterweight pointing downwards (CWD position). From L4, V1.0 up.
:hN#		Sleep Telescope: stop tracking, blank displays.
:hW#		Wake Up Telescope, restart tracking.
:h?#	2: Home/CWD Search in progress 1: Home/CWD Search done 0: Home/CWD Search failed or no :hP# or :hC# command was received.	Move to Home/CWD Position Status Inquiry
Move Telescope		Note: the directions mentioned depend upon the hemisphere of the observing site and the side of the mount the telescope actually is. Directions do not change when crossing one of the poles.
:MA#	0 1Object below horizon.# 2No object selected.# 3Manual Control.#	Slew to an object. The object selection had to be done by sending the Sz and Sa commands with the horizontal (Azimuth and Altitude) object coordinates. This command will be rejected while the system is in Manual Mode, f.i. identifying or selecting an object from the internal databases. From L4, V1.0 up.
:MF<n>	#	Move Find: for 0 For n=0 the position is changed ("wobbled") shaping an X with 5 arcmin legs moving at a quarter of the centering speed to detect faint objects.
:ML#	#	Move Lock: Slew commands :MS# and :MA# will be suppressed, error code 3 (Manual Control) will be returned.
:Ml#	#	Move Unlock: Slew commands :MS# or :MA# will be allowed to be executed again.
:Mf#	0 1Object below horizon.# 3Manual Control.# 4Position unreachable.#	Do a meridian flip and slew to the current coordinates.
:MM#	0 1Object below horizon.# 2No object selected.# 3Manual Control.# 4Position unreachable.# 5Not aligned.# 6Outside Limits.#	Slew to an object, doing a meridian flip if possible. Selection has had to be done locally (from Gemini's databases) or by sending the Sr and Sd commands with the equatorial object coordinates. This command will be rejected while the system is in Manual Mode, f.i. identifying or selecting an object from the internal databases.
:MS#	0 1Object below horizon.# 2No object selected.# 3Manual Control.# 4Position unreachable.# 5Not aligned.# 6Outside Limits.#	Slew to an object. Selection has had to be done locally (from Gemini's databases) or by sending the Sr and Sd commands with the equatorial object coordinates. This command will be rejected while the system is in Manual Mode, f.i. identifying or selecting an object from the internal databases.
:Me#		Move eastwards at the selected speed rate.
:Mw#		Move westwards at the selected speed rate.
:Mn#		Move northwards at the selected speed rate.
:Ms#		Move southwards at the selected speed rate.
Precision Guiding
:Ma<direction><arcsecs>#		Moves into <direction> "e", "w", "n", "s" for <arcsecs> arc seconds. <arcsecs> are converted into motor encoder ticks, the result must not exceed 255 or will be cut off modulo 256.
:Mi<direction><steps>#		Moves into <direction> "e", "w", "n", "s" for <steps> (1 <= steps <= 255) motor encoder ticks.
:Mg<direction><time>#		Moves into <direction> "e", "w", "n", "s" for <time> milliseconds. <time> is converted into motor encoder ticks, the result must not exceed 255 or will be cut off modulo 256.
Object/Observing
:OC#		Clears the Observing Log.
:OI<catalog-id><object-id>#		Select an object object-id from Gemini's internal databases catalog-id. Catalog-id is a character selecting one of the contigous catalogues: '1': Messier, '2': NGC, '3': IC, '4': Sh2, '7': SAO, ':': LDN, ';': LBN. Object-id is a numeric designation of the object in the catalogue; it can be followed by an extension character for NGC and IC catalogues.
:ON<name>#		Tells the Gemini system the name or identification of the selected object. If this command is not used, the name defaults to "PC Object". Using this command is recommended between the :Sr and :Sd commands for equatorial coordinates or the :Sz and :Sa commands for horizontal coordinates respectively. From L4, V1.0 up.
:OR#	<log entry>#	Reads the next line from the Observing Log.
:OS#		Points to the beginning of the Observing Log.
:Oc#		Delete all User Catalog entries.
:Od<object line>#		Download a User Catalog entry to the Gemini. The object line consist of the object name (up to 10 ASCII characters), a comma ',' as delimiter, Right Ascension <hh>:<mm>:<ss>, Declination {+-}<dd>:<mm>:<ss>. The coordinates have to be given for the epoch 2000.0.
:On#	<n>#	0 <= n <= 4096: Read current number of Gemini's User Catalog entries.
:Or#	<object line>#	Upload a User Catalog entry from Gemini.
:Os#		Points to the beginning of the User Catalog (for downloading).
Precession and Refraction
:p0#		No precession calculation necessary in the Gemini. Coordinates transfered to the Gemini are already precessed to the equinox of the date. Refraction is not calculated.
:p1#		Precession calculation is to be done by Gemini. Coordinates transfered to the Gemini refer to the standard epoch J2000.0. Refraction is not calculated.
:p2#		No precession calculation necessary in the Gemini. Coordinates transfered to the Gemini are already precessed to the equinox of the date. Refraction is calculated. From L4, V1.0 up.
:p3#		Precession calculation is to be done by Gemini. Coordinates transfered to the Gemini refer to the standard epoch J2000.0. Refraction is calculated. From L4, V1.0 up.
Precision
:P#	HIGH PRECISION  or LOW  PRECISION	Both strings are 14 characters long (there are 2 blanks between LOW and PRECISION).
:U#		Toggle between Low Precision (short) and High Precision (long) mode. The system is in High Precision mode after starting up.
Quit Moving
:Q#		Quit all movements mentioned below.
:Qe#		Quit movement eastwards.
:Qw#		Quit movement westwards.
:Qn#		Quit movement northwards.
:Qs#		Quit movement southwards.
Rate
:RC#		Rate Center. Subsequent Move commands will move at Centering Speed.
:RG#		Rate Guide. Subsequent Move commands will move at Guiding Speed.
:RM#		Rate Move. Subsequent Move commands will move at Centering Speed.
:RS#		Rate Slew. Subsequent Move commands will move at Slewing Speed.
Set
:Sa{+-}<dd>{*°}<mm># or :Sa{+-}<dd>{*°:}<mm>:<ss>#	0 if invalid or  1 if valid	Sets the object's altitude. A negative sign is ignored. Values greater than 90 degrees are set to 90 degrees. It is important that the :Sz# command has been send prior. If the coordinate selection is valid the object status is set to "Selected". From L4, V1.0 up.
:SB<n>#		Set LED Display Brightness Value(from L1, V2.0 up) n=0: 100% n=6: 6.6% n=7: blank display n=8: test mode (all pixels lit).
:SC<mm>/<dd>/<yy>#	0 if invalid or 1Updating planetary data# <24 blanks>#	Set Calendar Date: months mm, days dd, year yy of the civil time according to the timezone set. The internal calender/clock uses GMT.
:Sd{+-}<dd>{*°}<mm># or :Sd{+-}<dd>{*°:}<mm>:<ss>#	0 if invalid or  1 if valid	Sets the object's declination. It is important that the :Sr# command has been send prior. Internal calculations are done that may take up to 0.5 seconds. If the coordinate selection is valid the object status is set to "Selected".
:SE<hh>:<mm>:<ss>#	1	Set Alarm Time from the civil time hours hh, minutes mm and seconds ss. The timezone has to be set before using this command.
:SG{+-}hh#	1	Set the number of hours by which your local time differs from UTC. If your local time is earlier than UTC set a positive value, if later than UTC set a negative value. The time difference has to be set before setting the calendar date (SC) and local time (SL), since the Real Time Clock is running at UTC.
:SM<name string>#	1	Set name of the first site stored. The minimum length of site name strings is 1 byte, the maximum length 15 bytes.
:SN<name string>#	1	Set name of the second site stored.
:SO<name string>#	1	Set name of the third site stored.
:SP<name string>#	1	Set name of the forth site stored.
:SL<hh>:<mm>:<ss>#	1	Set RTC Time from the civil time hours hh, minutes mm and seconds ss. The timezone has to be set before using this command.
:Sg{+-}<ddd>*<mm>#	1 if valid	Sets the longitude of the observing site to ddd degrees and mm minutes. The longitude has to be specified positively for western latitudes (west of Greenwich, the plus sign may be omitted) and negatively for eastern longitudes. Alternatively, 360 degrees may be added to eastern longitudes.
:Sp#	No object!# or 1 if object coordinates were set.	Precess coordinate transmitted by means of :Sr and :Sd to the equinox of the date.
:Sr<hh>:<mm>.<m># or :Sr<hh>:<mm>:<ss>#	0 if invalid or  1 if valid	Sets the object's Right Ascension and the object status to "Not Selected". The :Sd# command has to follow to complete the selection. The subsequent use of the :ON...# command is recommended.
:St{+-}<dd>*<mm>#	1 if valid	Sets the latitude of the observing site to dd degrees, mm minutes. The minus sign indicates southern latitudes, the positive sign may be omitted.
:Sw<n>#	1 if valid	Sets the Slewing rate for the Move commands
:Sz<ddd>{*°}<mm># or :Sz<ddd>{*°:}<mm>:<ss>#	0 if invalid or  1 if valid	Sets the object's azimuth. From L4, V1.0 up.
Site Select
:W<n>#		Select stored Site n with 0<=n<=3.

Gemini Native Commands

Many of Gemini's system settings that cannot be accessed using the LX200-like command set can be read or modified using the native command set implemented in Gemini. The native commands follow a simple syntax:

<<id>:<checksum>#	<parameter value><checksum>#	Get Value(from L2 up)
><id>:<parameter value><checksum>#		Set Value(from L2 up)

Id's and possible values in Level 4, Version 1.0:
 

Id	Get Parameters	Set Parameters	Get Return Values	Description and Remarks
0..6			0: Custom Mount 1: GM8 2: G-11 3: HGM-200 4: MI-250 5: Titan 6: Titan50	Mount Type. Custom mount support (Id 0 and also commands 21..28) is new in L4. Attention: The CI-700 entry was replaced by the MI-250. CI-700 can be supported as a custom mount.
10, 11..15			10: Neither use encoder nor end switches 11: Use Encoder 12: Test Encoder 13: Ignore Encoder 14: Use end switches 15: Don't use end switches	Axis Encoder port status. 10 can be used for requesting.
21		{+-}80..720	{+-}80..720	RA worm gear ratio. The sign indicates the direction. Note: The 1,296,00 arcsec of a circle divided by the product of worm gear ratio, spur gear ratio and motor encoder resolution define the step size per encoder tick. Gemini L4 supports step sizes from 0.1 arcsec/tick to 2.5 arcsec/tick. Combinations exceeding this range are not allowed.
22		{+-}80..720	{+-}80..720	DEC worm gear ratio. The sign indicates the direction. See note for command 21.
23		20..150	20..150	RA spur gear ratio. See notes for commands 21 and 27.
24		20..150	20..150	DEC spur gear ratio. See note for command 21.
25		100..2048	100..2048	RA motor encoder resolution. See notes for commands 21 and 27.
26		100..2048	100..2048	DEC motor encoder resolution. See note for command 21.
27			2000..25600	Number of RA steps for one worm revolution (since is a product of spur ratio and motor encoder ratio,this command can only be used for reading out the maximum step count, not for setting it). Note: This product must not exceed 25600. If higher values are reported the combination of RA spur gear ratio and motor encoder is invalid.
28			2000..25600	Amount of DEC steps for one worm revolution (since is a product of spur ratio and motor encoder ratio,this command can only be used for reading out the maximum step count, not for setting it).
99			Decimal sum of 1: Telescope is Aligned, 2: Modeling in use, 4: Object is selected, 8: GoTo operation is performed, 16: RA limit reached, 32: Precess coordinates from J2000.0 to the equinox of the date.	Status Inquiry.
100		{+-}2048..32768	{+-}2048..32768	Encoder Resolution in RA.
110		{+-}2048..32768	{+-}2048..32768	Encoder Resolution in DEC.
120		20..2000	20..2000	Manual Slewing Speed.
130, 131..137			131: Sidereal 132: King Rate 133: Lunar 134: Solar 135: Terrestrial Mode 136: Closed Loop 137: Comet/User Defined	Tracking Rate. 130 can be used for requesting.
140		20..2000	20..2000	GoTo Slewing Speed.
150		0.2..0.8	0.2..0.8	Guiding Speed.
160, 161..163			161: Visual Mode 162: Photo Mode 163: All Speeds	Hand Controller Mode. 160 can be used for requesting.
170		1..255	1..255	Centering Speed.
180, 181..182			181: Alarm Off 182: Alarm On	Alarm Mode. 180 can be used for requesting.
190, 191..192			191: RA Motor stopped. 192: RA Motor moving.	RA Motor Movement. Command 190 can be used to obtain the current status, 191 for stopping and 192 for restarting the tracking.
200		0..255	0..255	TVC Step Count.
201		{+-}0..65535	{+-}0..65535	Modeling Parameter A (Polar Axis Misalignment in Azimuth), in seconds of arc.
202		{+-}0..65535	{+-}0..65535	Modeling Parameter E (Polar Axis Misalignment in Elevation), in seconds of arc.
203		{+-}0..65535	{+-}0..65535	Modeling Parameter NP (Axes Non-Perpendicularity at the Pole), in seconds of arc.
204		{+-}0..65535	{+-}0..65535	Modeling Parameter NE (Axes Non-Perpendicularity at the Equator), in seconds of arc.
205		{+-}0..65535	{+-}0..65535	Modeling Parameter IH (Index Error in Hour Angle), in seconds of arc.
206		{+-}0..65535	{+-}0..65535	Modeling Parameter ID (Index Error in Declination), in seconds of arc.
207		{+-}0..65535	{+-}0..65535	Modeling Parameter FR (Mirror Flop/Gear Play in RA), in seconds of arc.
208		{+-}0..65535	{+-}0..65535	Modeling Parameter FD (Mirror Flop/Gear Play in Declination), in seconds of arc.
209		{+-}0..65535	{+-}0..65535	Modeling Parameter CF (Counterweight & RA axis Flexure), in seconds of arc.
211		{+-}0..65535	{+-}0..65535	Modeling Parameter TF (Tube Flexure), in seconds of arc.
220			<ddd>d<mm>; <ddd>d<mm>	Set the respective Safety Limit to the current position. The Get function returns the eastern and western safety limits currently set. Note: Gemini will automatically compensate if you change hemispheres by swapping the eastern and western limits. This is because the mount is oriented northwards in the northern hemisphere and southwards in the southern hemispshere and so the side of the mount that faces east in the northern hemisphere will face west in the southern hemisphere and vice versa.
221		<ddd>d<mm>	<ddd>d<mm>	Get/Set eastern Safety Limit with respect to the meridian in degrees ddd and minutes mm. See note at command 220.
222		<ddd>d<mm>	<ddd>d<mm>	Get/Set western Safety Limit with respect to the meridian in degrees ddd and minutes mm. See note at command 220.
223		<ddd>d<mm>	<ddd>d<mm>	Get/Set Western GoTo limit (with respect to the meridian) in degrees ddd and minutes mm. GoTo operations will include a meridian flip if necessary to stay outside this limit. Note: If the RA angles usable for GoTo operations (East Safety Limit to Western GoTo limit are not sufficient to point to any location, GoTo operations to unreachable locations will be refused and the hand controller will display "Interrupted". A zero value (000d00) indicates that the GoTo Limit wasn't set yet and the default (002d30, allowing for at least 10 minutes tracking the object) is to be used.
230			<east>;<west>	Get physical Safety Limits in clusters of 256 motor encoder ticks. See note at command 221.
235			<ra_clusters>;<dec_clusters>	Get current physical RA and DEC axes position in clusters of 256 motor encoder ticks.
237			<ra_clusters>;<dec_clusters>	Get the size of an half circle of RA;DEC in clusters of 256 motor encoder ticks.
311		0..15	0..63	Feature Port Status. 4 bits (0..15) can be used for setting input/output bits, 6 bits (including two additional input only bits 16 and 32, extending the range to 0..63) are available for input.
312			0..15	Encoder Port Status. 4 bits (0..15) can be used for reading or setting input/output bits if it is not intended to connect mount axis encoders but to use these channels alternatively.
411		256..65535	256..65535	RA (comet) tracking rate divisor. The RA timer runs at 1.5 MHz, using this divisor the tracking rate can be adapted to the (mount dependent) speed of an object to be tracked. Attention: several internal prescalers may be used for further dividing down the frequency.
412		{+-}0..65535	{+-}0..65535	DEC comet tracking rate divisor. Attention: Changed Meaning! In L3, there was no timer for DEC comet tracking available, the DEC divisor referred to the number of RA steps to be done for one step in DEC. New in L4, the divisor value counts the number of internal timer ticks (at 22.888 18359 Hz) per one step in DEC, independently from RA. This corresponds to 0.657154312 arcsec/tick A zero value disables comet tracking DEC movements.
413		0..65535	0..65535	RA- (slow, eastwards) guiding rate divisor. While guiding eastwards, an additional 4x prescaler is active. A value of zero returned means a timer set to the maximum of 65536.
414		0..65535	0..65535	RA+ (fast, westwards) guiding rate divisor.
415		0..65535	0..65535	DEC guiding rate divisor.
501		0..PECmax	0..PECmax	Current RA PEC counter in steps, from 0 to the maximum step count per worm revolution PECmax. This maximum is the product of RA motor encoder resolution and spur gear ratio. It can be calculated multiplying the return values of the <23 and <25 commands or can be obtained directly by <27.
502			0.2 .. 0.8	Guiding Speed used for training PEC. Only valid if PEC was trained or PEC data were downloaded, see command 509. The set command can be used without parameters and sets the guiding speed back to the value used for training.
503		0..25600	0..25600	Maximum RA PEC counter in steps, from 0 to the maximum step count per worm revolution PECmax. This maximum is calculated as the product of RA motor encoder resolution and spur gear ratio at startup and whenever mount type or mount parameter are changed. Using this command, PECmax can be set to user defined values, f.i. to allow multiple worm cycles to be recorded.
504		0..255	0..255	Maximum consecutive RA PEC steps. 0 disables step supervision. Higher values define the maximum count of PEC steps in a row to enforce tiny corrections. After this maximum count is reached, normal tracking speed is reestablished.
509		0..63	0..63	PEC status. Decimal sum of: 1: PEC active, 2: freshly trained (not yet altered) PEC data are available as current PEC data, 4: PEC training in progress, 8: PEC training was just completed, 16: PEC training will start soon, 32: PEC data are available.
511	offset	value;offset;repeat count	value;repeat count	Currently used PEC data. [value] can be 0 (=normal tracking), 1 (RA-, guiding eastwards) or 8 (RA+, guiding westwards). [offset] ranges from 0 to PECmax-1. [repeat count] indicates the number of equal values starting at the given offset.
512	offset	value;offset;repeat count	value;repeat count	Saved PEC data. [value] can be 0 (=normal tracking), 1 (RA-, guiding eastwards) or 8 (RA+, guiding westwards). [offset] ranges from 0 to PECmax-1; [repeat count] indicates the number of equal values starting at the given offset.
521			RA-/slow step count; normal step count; RA+/fast step count	PEC statistics. Three decimal values, summing up the steps at the three speeds.
43690				Reset to Losmandy HGM default values.
43691				Reset to Mountain Instruments default values.
65533				Reboot the Gemini controller software, enforcing a Cold Start.
65534				Reboot the Gemini controller software.
65535				Reboot the Gemini controller software.

Using the native commands:

• The Identification tag is interpreted as an integer value, leading zeros are ignored.
• Parameters are separated from the Id and from each other by hyphens.
• The checksum for the native commands is calculated by a bytewise XOR operation of the transmitted characters, including the Get/Set command sign ('<', '>') and colon ':'. The highest significant bit of the result is cleared (modulo 128 operation) and 64 is added.
• Undefined Ids are ignored in Set operations. For Get operations, only a hash mark will be returned.
• In Debug Mode, the expected and the received checksum are displayed on the hand controller display in hexadecimal format whenever a discrepancy is detected. A command sent with a wrong checksum will not be executed.

Examples

• Get the Mount Type: "<0:v" and "<00:F#" are equivalent.
• "<1:w#" and "<2:t#" and "<3:u#" will deliver the same result, f.i. the string "1q#" if the mount type is set to GM-8 or "2r#" if G-11 is selected.

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