Wiki source code of LSS - Communication Protocol

Version 94.1 by Coleman Benson on 2019/02/01 12:00

79.1	1	(% class="wikigeneratedid" id="HTableofContents" %)
	2	Table of Contents
67.1	3
64.5	4	{{toc depth="3"/}}
	5
93.1	6	= Serial Protocol Concept =
64.19	7
94.1	8	The custom Lynxmotion Smart Servo (LSS) serial protocol was created in order to be as simple and straightforward as possible from a user perspective ("human readable format"), while at the same time compact and robust yet highly versatile. The protocol was based on Lynxmotion's SSC-32 RC servo controller and almost everything one might expect to be able to configure for a smart servo motor is available.
1.1	9
94.1	10	In order to have servos react differently when commands are sent to all servos in a serial bus, the first step a user should take is to assign a different ID number to each servo (explained below). Once this has been done, only the servo(s) which have been assigned to the ID sent as part of the command will follow that command. There is currently no CRC / checksum implemented as part of the protocol.
93.1	11
64.2	12	== Session ==
1.1	13
	14	A "session" is defined as the time between when the servo is powered ON to when it is powered OFF or reset.
	15
	16	== Action Commands ==
	17
94.1	18	Action commands tell the servo, within that session, to do something (i.e. "take an action"). The types of action commands which can be sent are described below, and they cannot be combined with other commands such as queries or configurations. Only one action command can be sent at a time. Action commands are session-specific, therefore once a servo is power cycled, it will not have any "memory" of previous actions or virtual positions (described below on this page). Action commands are sent serially to the servo's Rx pin and must be sent in the following format:
1.1	19
	20	1. Start with a number sign # (U+0023)
	21	1. Servo ID number as an integer
	22	1. Action command (one to three letters, no spaces, capital or lower case)
	23	1. Action value in the correct units with no decimal
	24	1. End with a control / carriage return '<cr>'
	25
	26	(((
	27	Ex: #5PD1443<cr>
	28
94.1	29	This sends a serial command to all servo's Rx pins which are connected to the bus and only servo(s) with ID #5 will move to a position in tenths of degrees ("PD") of 144.3 degrees. Any servo on the bus which does not have ID 5 will take no action when receiving this command.
1.1	30
65.2	31	== Action Modifiers ==
1.1	32
94.1	33	Only two commands can be used as action modifiers: Timed Move (T) and Speed (S) described below. Action modifiers can only be used with certain action commands. The format to include a modifier is:
1.1	34
	35	1. Start with a number sign # (U+0023)
	36	1. Servo ID number as an integer
	37	1. Action command (one to three letters, no spaces, capital or lower case)
	38	1. Action value in the correct units with no decimal
	39	1. Modifier command (one letter)
	40	1. Modifier value in the correct units with no decimal
	41	1. End with a control / carriage return '<cr>'
	42
	43	Ex: #5P1456T1263<cr>
	44
94.1	45	This results in the servo with ID #5 rotating from the current angular position to a pulse position ("P") of 1456 in a time ("T") of 1263 milliseconds.
1.1	46	)))
	47
16.1	48	== Configuration Commands ==
	49
94.1	50	Configuration commands and corresponding values affect a servo's defaults which are written to and read from the servo's EEPROM. These configurations are retained in memory after the servo is reset or power is cut / lost. Some configuration commands affect the session, while others do not (see each command for details). Not all action commands have a corresponding configuration and vice versa. More information about which configuration commands are retained when in RC mode can be found on the [[LSS - RC PWM page>>doc:Lynxmotion Smart Servo (LSS).LSS - RC PWM.WebHome]]. Configuration commands are not cumulative, in that if two configurations are sent, one after the next, only the last configuration is used and stored. The format to send a configuration command is identical to that of an action command:
16.1	51
	52	1. Start with a number sign # (U+0023)
	53	1. Servo ID number as an integer
	54	1. Configuration command (two to three letters, no spaces, capital or lower case)
	55	1. Configuration value in the correct units with no decimal
	56	1. End with a control / carriage return '<cr>'
	57
	58	Ex: #5CO-50<cr>
	59
94.1	60	This configures an absolute origin offset ("CO") with respect to factory origin to servo with ID #5 and changes the offset for that session to -5.0 degrees (50 tenths of degrees). Once the servo is powered off and then powered on, zeroing the servo will cause it to move to -5.0 degrees with respect to the factory origin and report its position as 0 degrees. Configuration commands can be undone / reset either by sending the servo's default value for that configuration, or by doing a factory reset (clears all configurations) described below.
16.1	61
1.1	62	== Query Commands ==
	63
94.1	64	Query commands request information from the servo. They are received via the Rx pin of the servo, and the servo's reply is sent via the servo's Tx pin. Using separate lines for Tx and Rx is called "full duplex". Query commands are also similar to action and configuration commands and must use the following format:
1.1	65
	66	1. Start with a number sign # (U+0023)
	67	1. Servo ID number as an integer
	68	1. Query command (one to three letters, no spaces, capital or lower case)
	69	1. End with a control / carriage return '<cr>'
	70
	71	(((
	72	Ex: #5QD<cr>Query position in degrees for servo #5
	73	)))
	74
	75	(((
93.1	76	The query will return a serial string (almost instantaneously) via the servo's Tx pin with the following format:
1.1	77
93.1	78	1. Start with an asterisk * (U+002A)
1.1	79	1. Servo ID number as an integer
	80	1. Query command (one to three letters, no spaces, capital letters)
	81	1. The reported value in the units described, no decimals.
	82	1. End with a control / carriage return '<cr>'
	83
94.1	84	There is currently no option to control how fast a servo replies after it has received a query command, therefore when sending a query command to the bus, the controller should be prepared to immediately "listen" for and parse the reply. Sending multiple queries on a bus in fast succession may result in replies overlapping and giving incorrect or corrupt data. As such, the controller should receive a reply before sending a new command. A reply to the query sent above might be:
93.1	85
1.1	86	(((
	87	Ex: *5QD1443<cr>
	88	)))
	89
94.1	90	This indicates that servo #5 is currently at 144.3 degrees (1443 tenths of degrees).
1.1	91
16.1	92	Session vs Configuration Query
1.1	93
94.1	94	By default, the query command returns the sessions' value. Should no action commands have been sent to change the session value, it will return the value saved in EEPROM which will either be the servo's default, or modified with a configuration command. In order to query the value stored in EEPROM (configuration), add a '1' to the query command:
1.1	95
94.1	96	Ex: #5CSR20<cr> immediately sets the maximum speed for servo #5 to 20rpm (explained below) and changes the value in memory.
1.1	97
94.1	98	After RESET, a command of #5SR4<cr> sets the session's speed to 4rpm, but does not change the configuration value in memory. Therefore:
1.1	99
94.1	100	#5QSR<cr> would return *5QSR4<cr> which represents the value for that session, whereas
1.1	101
16.1	102	#5QSR1<cr> would return *5QSR20<cr> which represents the value in EEPROM
56.1	103
65.2	104	== Virtual Angular Position ==
56.1	105
94.1	106	The ability to store a "virtual angular position" is a feature which allows for rotation beyond 360 degrees, permitting multiple rotations of the output horn, moving the center position and more. In virtual position mode, the "absolute position" would be the angle of the output shaft with respect to a 360.0 degree circle, and can be obtained by taking the modulus (with respect to 360 degrees) of the value. For example if the virtual position is reported as 15335 (or 1533.5 degrees), taking the modulus would give 93.5 degrees (3600 * 4 + 935 = 15335) as the absolute position (assuming no origin offset).
56.1	107
	108	[[image:LSS-servo-positions.jpg]]
	109
94.1	110	In this example, the gyre direction (explained below, a.k.a. "rotation direction") is positive (clockwise), and origin offset has not been modified. Each square represents 30 degrees. The following command is sent:
56.1	111
93.1	112	#1D-300<cr> This causes the servo to move to -30.0 degrees (green arrow)
56.1	113
	114	#1D2100<cr> This second position command is sent to the servo, which moves it to 210.0 degrees (orange arrow)
	115
94.1	116	#1D-4200<cr> This next command rotates the servo counterclockwise to a position of -420 degrees (red arrow), which means one full rotation of 360 degrees plus 60.0 degrees (420.0 - 360.0), with a virtual position of -420.0 degrees.
56.1	117
	118	Although the final physical position would be the same as if the servo were commanded to move to -60.0 degrees, the servo is in fact at -420.0 degrees.
	119
	120	#1D4800<cr> This new command is sent which would then cause the servo to rotate from -420.0 degrees to 480.0 degrees (blue arrow), which would be a total of 900 degrees of clockwise rotation, or 2.5 complete rotations.
	121
	122	#1D3300<cr> would cause the servo to rotate from 480.0 degrees to 330.0 degrees (yellow arrow).
	123
	124	If / once the servo loses power or is power cycled, it also loses the virtual position associated with that session. For example, if the virtual position was 480.0 degrees before power is cycled, upon power up the servo's position will be read as +120.0 degrees from zero (assuming center position has not been modified).
16.1	125	)))
1.1	126
	127	= Command List =
	128
93.1	129	\|= #\|=Description\|= Action\|= Query\|= Config\|= RC\|= Serial\|= Units\|=(% style="width: 510px;" %) Notes\|=(% style="width: 113px;" %)Default Value
	130	\| 1\|[[Limp>>\|\|anchor="H1.Limp28L29"]]\| L\| \| \| \| ✓\|none\|(% style="width:510px" %) \|(% style="text-align:center; width:113px" %)
	131	\| 2\|[[Halt & Hold>>\|\|anchor="H2.Halt26Hold28H29"]]\| H\| \| \| \| ✓\|none\|(% style="width:510px" %) \|(% style="text-align:center; width:113px" %)
	132	\| 3\|[[Timed move>>\|\|anchor="H3.Timedmove28T29"]]\| T\| \| \| \| ✓\|milliseconds\|(% style="width:510px" %) Modifier only for {P, D, MD}\|(% style="text-align:center; width:113px" %)
	133	\| 4\|[[Speed>>\|\|anchor="H4.Speed28S29"]]\| S\| \| \| \| ✓\|microseconds / second\|(% style="width:510px" %) Modifier only {P}\|(% style="text-align:center; width:113px" %)
94.1	134	\| 5\|[[Move in Degrees (relative)>>\|\|anchor="H5.28Relative29MoveinDegrees28MD29"]]\| MD\| \| \| \| ✓\|tenths of degrees (ex 325 = 32.5 degrees)\|(% style="width:510px" %) \|(% style="text-align:center; width:113px" %)
	135	\| 6\|[[Origin Offset>>\|\|anchor="H6.OriginOffsetAction28O29"]]\| O\| QO\| CO\| ✓\| ✓\|tenths of degrees (ex 91 = 9.1 degrees)\|(% style="width:510px" %) \|(% style="text-align:center; width:113px" %)(((
93.1	136	0
92.1	137	)))
94.1	138	\| 7\|[[Angular Range>>\|\|anchor="H7.AngularRange28AR29"]]\| AR\| QAR\| CAR\| ✓\| ✓\|tenths of degrees \|(% style="width:510px" %) \|(% style="text-align:center; width:113px" %)(((
93.1	139	1800
92.1	140	)))
93.1	141	\| 8\|[[Position in Pulse>>\|\|anchor="H8.PositioninPulse28P29"]]\| P\| QP\| \| \| ✓\|microseconds\|(% style="width:510px" %)(((
	142	Inherited from SSC-32 serial protocol
	143	)))\|(% style="text-align:center; width:113px" %)
94.1	144	\| 9\|[[Position in Degrees>>\|\|anchor="H9.PositioninDegrees28D29"]]\| D\| QD\| \| \| ✓\|tenths of degrees \|(% style="width:510px" %) \|(% style="text-align:center; width:113px" %)
93.1	145	\| 10\|[[Wheel mode in Degrees>>\|\|anchor="H10.WheelModeinDegrees28WD29"]]\| WD\| QWD\| \| \| ✓\|tenths of degrees per second (ex 248 = 24.8 degrees per second)\|(% style="width:510px" %)A.K.A. "Speed mode" or "Continuous rotation"\|(% style="text-align:center; width:113px" %)
	146	\| 11\|[[Wheel mode in RPM>>\|\|anchor="H11.WheelModeinRPM28WR29"]]\| WR\| QWR\| \| \| ✓\| rpm\|(% style="width:510px" %)A.K.A. "Speed mode" or "Continuous rotation"\|(% style="text-align:center; width:113px" %)
94.1	147	\| 12\|[[Max Speed in Degrees>>\|\|anchor="H12.SpeedinDegrees28SD29"]]\| SD\| QSD\|CSD\| ✓\| ✓\|tenths of degrees per second \|(% style="width:510px" %)(((
	148	QSD: Add modifier "2" for instantaneous speed.
	149
	150	SD overwrites SR / CSD overwrites CSR and vice-versa.
	151	)))\|(% style="text-align:center; width:113px" %)Max per servo
	152	\| 13\|[[Max Speed in RPM>>\|\|anchor="H13.SpeedinRPM28SR29"]]\| SR\| QSR\|CSR\| ✓\| ✓\|rpm\|(% style="width:510px" %)(((
	153	QSR: Add modifier "2" for instantaneous speed
	154
	155	SR overwrites SD / CSR overwrites CSD and vice-versa.
	156	)))\|(% style="text-align:center; width:113px" %)Max per servo
93.1	157	\| 16\|[[LED Color>>\|\|anchor="H16.RGBLED28LED29"]]\| LED\| QLED\| CLED\| ✓\| ✓\|none (integer from 0 to 8)\|(% style="width:510px" %)0=Off (black); 1=Red 2=Green; 3=Blue; 4=Yellow; 5=Cyan; 6=Magenta; 7=White;\|(% style="text-align:center; width:113px" %)7
	158	\| 17\|[[ID #>>\|\|anchor="H17.IdentificationNumber"]]\| \| QID\| CID\| \| ✓\|none (integer from 0 to 250)\|(% style="width:510px" %)Note: ID 254 is a "broadcast" which all servos respond to\|(% style="text-align:center; width:113px" %)0
	159	\| 18\|[[Baud rate>>\|\|anchor="H18.BaudRate"]]\| B\| QB\| CB\| \| ✓\|none (integer)\|(% style="width:510px" %) \|(% style="text-align:center; width:113px" %)9600
94.1	160	\| 19\|[[Gyre direction (G)>>\|\|anchor="H19.GyreRotationDirection"]]\| G\| QG\| CG\| ✓\| ✓\|none \|(% style="width:510px" %)Gyre / rotation direction where 1= CW (clockwise) -1 = CCW (counter-clockwise)\|(% style="text-align:center; width:113px" %)1
	161	\| 20\|[[First Position (Pulse)>>\|\|anchor="H20.First2InitialPosition28pulse29"]]\| \| QFP\|CFP \| ✓\| ✓\|none \|(% style="width:510px" %)CFP overwrites CFD and vice-versa\|(% style="text-align:center; width:113px" %)(((
92.1	162	Limp
	163	)))
94.1	164	\| 21\|[[First Position (Degrees)>>\|\|anchor="H21.First2InitialPosition28Degrees29"]]\| \| QFD\|CFD\| ✓\| ✓\|none \|(% style="width:510px" %)CFD overwrites CFP and vice-versa\|(% style="text-align:center; width:113px" %)Limp
93.1	165	\| 22\|[[Target (Degree) Position>>\|\|anchor="H22.QueryTargetPositioninDegrees28QDT29"]]\| \| QDT\| \| \| ✓\|tenths of degrees (ex 325 = 32.5 degrees; 91 = 9.1 degrees)\|(% style="width:510px" %) \|(% style="text-align:center; width:113px" %)
	166	\| 23\|[[Model String>>\|\|anchor="H23.QueryModelString28QMS29"]]\| \| QMS\| \| \| \|none (string)\|(% style="width:510px" %) Recommended to determine the model\|(% style="text-align:center; width:113px" %)
	167	\| 23b\|[[Model>>\|\|anchor="H23b.QueryModel28QM29"]]\| \| QM\| \| \| \|none (integer)\|(% style="width:510px" %) Returns a raw value representing the three model inputs (36 bit)\|(% style="text-align:center; width:113px" %)
	168	\| 24\|[[Serial Number>>\|\|anchor="H24.QuerySerialNumber28QN29"]]\| \| QN\| \| \| \|none (integer)\|(% style="width:510px" %) \|(% style="text-align:center; width:113px" %)
	169	\| 25\|[[Firmware version>>\|\|anchor="H25.QueryFirmware28QF29"]]\| \| QF\| \| \| \|none (integer)\|(% style="width:510px" %) \|(% style="text-align:center; width:113px" %)
	170	\| 26\|[[Query (general status)>>\|\|anchor="H26.QueryStatus28Q29"]]\| \| Q\| \| \| ✓\|none (integer from 1 to 8)\|(% style="width:510px" %) See command description for details\|(% style="text-align:center; width:113px" %)
	171	\| 27\|[[Voltage>>\|\|anchor="H27.QueryVoltage28QV29"]]\| \| QV\| \| \| ✓\|millivolts (ex 5936 = 5936mV = 5.936V)\|(% style="width:510px" %) \|(% style="text-align:center; width:113px" %)
	172	\| 28\|[[Temperature>>\|\|anchor="H28.QueryTemperature28QT29"]]\| \| QT\| \| \| ✓\|tenths of degrees Celsius\|(% style="width:510px" %)Max temp before error: 85°C (servo goes limp)\|(% style="text-align:center; width:113px" %)
	173	\| 29\|[[Current>>\|\|anchor="H29.QueryCurrent28QC29"]]\| \| QC\| \| \| ✓\|milliamps (ex 200 = 0.2A)\|(% style="width:510px" %) \|(% style="text-align:center; width:113px" %)
	174	\| 30\|[[RC Mode>>\|\|anchor="H30.RCMode28CRC29"]]\| \| \|CRC\| \|✓\|none\|(% style="width:510px" %)(((
48.1	175	CRC: Add modifier "1" for RC-position mode.
	176	CRC: Add modifier "2" for RC-wheel mode.
	177	Any other value for the modifier results in staying in smart mode.
	178	Puts the servo into RC mode. To revert to smart mode, use the button menu.
93.1	179	)))\|(% style="text-align:center; width:113px" %)Serial
	180	\|31\|[[RESET>>\|\|anchor="H31.RESET"]]\| \| \| \| \| ✓\|none\|(% style="width:510px" %)Soft reset. See command for details.\|(% style="text-align:center; width:113px" %)
	181	\|32\|[[DEFAULT>>\|\|anchor="H32.DEFAULTA026CONFIRM"]]\| \| \| \| \|✓\|none\|(% style="width:510px" %)Revert to firmware default values. See command for details\|(% style="text-align:center; width:113px" %)
	182	\|33\|[[UPDATE>>\|\|anchor="H33.UPDATEA026CONFIRM"]]\| \| \| \| \|✓\|none\|(% style="width:510px" %)Update firmware. See command for details.\|(% style="text-align:center; width:113px" %)
1.1	183
93.1	184	== Advanced ==
	185
	186	\|= #\|=Description\|= Action\|= Query\|= Config\|= RC\|= Serial\|= Units\|=(% style="width: 510px;" %) Notes\|=(% style="width: 113px;" %)Default Value
	187	\| 1\|[[Angular Stiffness>>\|\|anchor="H14.AngularStiffness28AS29"]]\| AS\| QAS\|CAS\| ✓\| ✓\|none\|(% style="width:510px" %)-4 to +4, but suggested values are between 0 to +4\|(% style="text-align:center; width:113px" %)0
	188	\| 2\|[[Angular Holding Stiffness>>\|\|anchor="H15.AngularHoldStiffness28AH29"]]\|AH\|QAH\|CAH\| \| ✓\|none\|(% style="width:510px" %)-10 to +10, with default as 0. \|(% style="text-align:center; width:113px" %)1
	189	\| 3\|[[Angular Acceleration>>\|\|anchor="H15b:AngularAcceleration28AA29"]]\|AA\|QAA\|CAA\| \| ✓\|degrees per second squared\|(% style="width:510px" %)Increments of 10 degrees per second squared\|(% style="text-align:center; width:113px" %)
	190	\| 4\|[[Angular Deceleration>>\|\|anchor="H15c:AngularDeceleration28AD29"]]\|AD\|QAD\|CAD\| \| ✓\|degrees per second squared\|(% style="width:510px" %)Increments of 10 degrees per second squared\|(% style="text-align:center; width:113px" %)
	191	\| 5\|[[Enable Motion control>>\|\|anchor="H15d:MotionControl28MC29"]]\|EM\|QEM\| \| \| ✓\|none\|(% style="width:510px" %)EM0 to disable motion control, EM1 to enable. Session specific / does not survive power cycles\|(% style="text-align:center; width:113px" %)
	192	\| 6\|[[Configure LED Blinking>>\|\|anchor="H16b.ConfigureLEDBlinking28CLB29"]]\| \| \| CLB\| ✓\| \|none (integer from 0 to 63)\|(% style="width:510px" %)0=No blinking, ; 63=Always blink; Blink while: 1=Limp; 2=Holding 4=Accel; 8=Decel; 16=Free 32=Travel;\|(% style="text-align:center; width:113px" %)
	193	\| \| \| \| \| \| \| \| \|(% style="width:510px" %) \|(% style="text-align:center; width:113px" %)
	194
64.3	195	== Details ==
1.1	196
64.15	197	====== __1. Limp (L)__ ======
1.1	198
	199	Example: #5L<cr>
	200
	201	This action causes the servo to go "limp". The microcontroller will still be powered, but the motor will not. As an emergency safety feature, should the robot not be doing what it is supposed to or risks damage, use the broadcast ID to set all servos limp #254L<cr>.
	202
64.16	203	====== __2. Halt & Hold (H)__ ======
1.1	204
	205	Example: #5H<cr>
	206
	207	This action overrides whatever the servo might be doing at the time the command is received (accelerating, moving continuously etc.) and causes it to stop immediately and hold that position.
	208
64.16	209	====== __3. Timed move (T)__ ======
1.1	210
	211	Example: #5P1500T2500<cr>
	212
	213	Timed move can be used only as a modifier for a position (P) action. The units are in milliseconds, so a timed move of 2500 milliseconds would cause the servo to rotate from its current position to the desired position in 2.5 seconds. This command is in place to ensure backwards compatibility with the SSC-32 / 32U protocol.
	214
72.1	215	Note: If the calculated speed at which a servo must rotate for a timed move is greater than its maximum speed (which depends on voltage and load), then it will move at its maximum speed, and the time of the move may be longer than requested.
	216
64.28	217	====== __4. Speed (S)__ ======
1.1	218
	219	Example: #5P1500S750<cr>
	220
	221	This command is a modifier only for a position (P) action and determines the speed of the move in microseconds per second. A speed of 750 microseconds would cause the servo to rotate from its current position to the desired position at a speed of 750 microseconds per second. This command is in place to ensure backwards compatibility with the SSC-32 / 32U protocol.
	222
64.16	223	====== __5. (Relative) Move in Degrees (MD)__ ======
1.1	224
	225	Example: #5MD123<cr>
	226
	227	The relative move command causes the servo to read its current position and move the specified number of tenths of degrees in the corresponding position. For example if the servo is set to rotate CW (default) and an MD command of 123 is sent to the servo, it will cause the servo to rotate clockwise by 12.3 degrees. Negative commands would cause the servo to rotate in the opposite configured direction.
	228
64.16	229	====== __6. Origin Offset Action (O)__ ======
1.1	230
	231	Example: #5O2400<cr>
	232
	233	This command allows you to temporarily change the origin of the servo in relation to the factory zero position. The setting will be lost upon servo reset / power cycle. Origin offset commands are not cumulative and always relate to factory zero. Note that for a given session, the O command overrides the CO command. In the first image, the origin at factory offset '0' (centered).
	234
	235	[[image:LSS-servo-default.jpg]]
	236
	237	In the second image, the origina, as well as the angular range (explained below) have been shifted by 240.0 degrees:
	238
	239	[[image:LSS-servo-origin.jpg]]
	240
	241	Origin Offset Query (QO)
	242
	243	Example: #5QO<cr> Returns: *5QO-13
	244
	245	This allows you to query the angle (in tenths of degrees) of the origin in relation to the factory zero position.
	246
	247	Configure Origin Offset (CO)
	248
	249	Example: #5CO-24<cr>
	250
	251	This command allows you to change the origin of the servo in relation to the factory zero position in EEPROM. The setting will be saved upon servo reset / power cycle. Origin offset configuration commands are not cumulative and always relate to factory zero. The new origin is also used in RC mode.
	252
64.16	253	====== __7. Angular Range (AR)__ ======
1.1	254
	255	Example: #5AR1800<cr>
	256
	257	This command allows you to temporarily change the total angular range of the servo in tenths of degrees. This applies to the Position in Pulse (P) command and RC mode. The default for (P) and RC mode is 1800 (180.0 degrees total, or ±90.0 degrees). In the first image,
	258
	259	[[image:LSS-servo-default.jpg]]
	260
	261	Here, the angular range has been restricted to 180.0 degrees, or -90.0 to +90.0. The center has remained unchanged.
	262
	263	[[image:LSS-servo-ar.jpg]]
	264
	265	The angular range action command (ex. #5AR1800<cr>) and origin offset action command (ex. #5O-1200<cr>) an be used to move both the center and limit the angular range:
	266
	267	[[image:LSS-servo-ar-o-1.jpg]]
	268
	269	Query Angular Range (QAR)
	270
	271	Example: #5QAR<cr> might return *5AR2756
	272
	273	Configure Angular Range (CAR)
	274
	275	This command allows you to change the total angular range of the servo in tenths of degrees in EEPROM. The setting will be saved upon servo reset / power cycle.
	276
64.16	277	====== __8. Position in Pulse (P)__ ======
1.1	278
	279	Example: #5P2334<cr>
	280
11.1	281	The position in PWM pulses was retained in order to be backward compatible with the SSC-32 / 32U protocol. This relates the desired angle with an RC standard PWM pulse and is further explained in the SSC-32 and SSC-32U manuals found on Lynxmotion.com. Without any modifications to configuration considered, and a ±90.0 degrees standard range where 1500 microseconds is centered, a pulse of 2334 would set the servo to 165.1 degrees. Valid values for P are [500, 2500]. Values outside this range are corrected to end points.
1.1	282
	283	Query Position in Pulse (QP)
	284
37.1	285	Example: #5QP<cr> might return *5QP2334
1.1	286
11.1	287	This command queries the current angular position in PWM "units". The user must take into consideration that the response includes any angular range and origin configurations in order to determine the actual angle.
37.1	288	Valid values for QP are {-500, [500, 2500], -2500}. Values outside the [500, 2500] range are given a negative corresponding end point value to indicate they are out of bounds (note that if the servo is physically located at one of the endpoints, it may return a negative number if it is a fraction of a degree beyond the position).
1.1	289
64.16	290	====== __9. Position in Degrees (D)__ ======
1.1	291
	292	Example: #5PD1456<cr>
	293
	294	This moves the servo to an angle of 145.6 degrees, where the center (0) position is centered. Negative values (ex. -176 representing -17.6 degrees) are used. A full circle would be from -1800 to 1800 degrees. A value of 2700 would be the same angle as -900, except the servo would move in a different direction.
	295
	296	Larger values are permitted and allow for multi-turn functionality using the concept of virtual position.
	297
	298	Query Position in Degrees (QD)
	299
37.1	300	Example: #5QD<cr> might return *5QD132<cr>
1.1	301
37.1	302	This means the servo is located at 13.2 degrees.
	303
64.16	304	====== __10. Wheel Mode in Degrees (WD)__ ======
1.1	305
	306	Ex: #5WD900<cr>
	307
	308	This command sets the servo to wheel mode where it will rotate in the desired direction at the selected speed. The example above would have the servo rotate at 90.0 degrees per second clockwise (assuming factory default configurations).
	309
	310	Query Wheel Mode in Degrees (QWD)
	311
	312	Ex: #5QWD<cr> might return *5QWD900<cr>
	313
	314	The servo replies with the angular speed in tenths of degrees per second. A negative sign would indicate the opposite direction (for factory default a negative value would be counter clockwise).
	315
64.16	316	====== __11. Wheel Mode in RPM (WR)__ ======
1.1	317
	318	Ex: #5WR40<cr>
	319
	320	This command sets the servo to wheel mode where it will rotate in the desired direction at the selected rpm. Wheel mode (a.k.a. "continuous rotation") has the servo operate like a geared DC motor. The servo's maximum rpm cannot be set higher than its physical limit at a given voltage. The example above would have the servo rotate at 40 rpm clockwise (assuming factory default configurations).
	321
	322	Query Wheel Mode in RPM (QWR)
	323
	324	Ex: #5QWR<cr> might return *5QWR40<cr>
	325
	326	The servo replies with the angular speed in rpm. A negative sign would indicate the opposite direction (for factory default a negative value would be counter clockwise).
	327
64.16	328	====== __12. Speed in Degrees (SD)__ ======
1.1	329
	330	Ex: #5SD1800<cr>
	331
	332	This command sets the servo's maximum speed for action commands in tenths of degrees per second for that session. In the example above, the servo's maximum speed for that session would be set to 180.0 degrees per second. Therefore maximum speed for actions can be set "on the fly". The servo's maximum speed cannot be set higher than its physical limit at a given voltage. SD overrides CSD (described below) for that session. Upon reset or power cycle, the servo reverts to the value associated with CSD as described below. Note that SD and SR (described below) are effectively the same, but allow the user to specify the speed in either unit. The last command (either SR or SD) is what the servo uses for that session.
	333
	334	Query Speed in Degrees (QSD)
	335
	336	Ex: #5QSD<cr> might return *5QSD1800<cr>
	337
25.1	338	By default QSD will return the current session value, which is set to the value of CSD as reset/power cycle and changed whenever a SD/SR command is processed.
23.1	339	If #5QSD1<cr> is sent, the configured maximum speed (CSD value) will be returned instead. You can also query the current speed using "2" and the current target travel speed using "3". See the table below for an example:
1.1	340
24.1	341	\|Command sent\|Returned value (1/10 °)
32.1	342	\|ex: #5QSD<cr>\|Session value for maximum speed (set by latest SD/SR command)
	343	\|ex: #5QSD1<cr>\|Configured maximum speed (set by CSD/CSR)
	344	\|ex: #5QSD2<cr>\|Instantaneous speed (same as QWD)
	345	\|ex: #5QSD3<cr>\|Target travel speed
23.1	346
1.1	347	Configure Speed in Degrees (CSD)
	348
	349	Ex: #5CSD1800<cr>
	350
	351	Using the CSD command sets the servo's maximum speed which is saved in EEPROM. In the example above, the servo's maximum speed will be set to 180.0 degrees per second. When the servo is powered on (or after a reset), the CSD value is used. Note that CSD and CSR (described below) are effectively the same, but allow the user to specify the speed in either unit. The last command (either CSR or CSD) is what the servo uses for that session.
	352
64.16	353	====== __13. Speed in RPM (SR)__ ======
1.1	354
	355	Ex: #5SD45<cr>
	356
	357	This command sets the servo's maximum speed for action commands in rpm for that session. In the example above, the servo's maximum speed for that session would be set to 45rpm. Therefore maximum speed for actions can be set "on the fly". The servo's maximum speed cannot be set higher than its physical limit at a given voltage. SD overrides CSD (described below) for that session. Upon reset or power cycle, the servo reverts to the value associated with CSD as described below. Note that SD (described above) and SR are effectively the same, but allow the user to specify the speed in either unit. The last command (either SR or SD) is what the servo uses for that session.
	358
	359	Query Speed in Degrees (QSR)
	360
	361	Ex: #5QSR<cr> might return *5QSR45<cr>
	362
25.1	363	By default QSR will return the current session value, which is set to the value of CSR as reset/power cycle and changed whenever a SD/SR command is processed.
	364	If #5QSR1<cr> is sent, the configured maximum speed (CSR value) will be returned instead. You can also query the current speed using "2" and the current target travel speed using "3". See the table below for an example:
1.1	365
25.1	366	\|Command sent\|Returned value (1/10 °)
32.1	367	\|ex: #5QSR<cr>\|Session value for maximum speed (set by latest SD/SR command)
	368	\|ex: #5QSR1<cr>\|Configured maximum speed (set by CSD/CSR)
	369	\|ex: #5QSR2<cr>\|Instantaneous speed (same as QWR)
	370	\|ex: #5QSR3<cr>\|Target travel speed
1.1	371
25.1	372	Configure Speed in RPM (CSR)
	373
1.1	374	Ex: #5CSR45<cr>
	375
25.1	376	Using the CSR command sets the servo's maximum speed which is saved in EEPROM. In the example above, the servo's maximum speed will be set to 45rpm. When the servo is powered on (or after a reset), the CSR value is used. Note that CSD and CSR are effectively the same, but allow the user to specify the speed in either unit. The last command (either CSR or CSD) is what the servo uses for that session.
1.1	377
64.16	378	====== __14. Angular Stiffness (AS)__ ======
15.1	379
31.1	380	The servo's rigidity / angular stiffness can be thought of as (though not identical to) a damped spring in which the value affects the stiffness and embodies how much, and how quickly the servo tried keep the requested position against changes.
15.1	381
31.1	382	A positive value of "angular stiffness":
15.1	383
	384	* The more torque will be applied to try to keep the desired position against external input / changes
	385	* The faster the motor will reach its intended travel speed and the motor will decelerate faster and nearer to its target position
	386
	387	A negative value on the other hand:
	388
	389	* Causes a slower acceleration to the travel speed, and a slower deceleration
	390	* Allows the target position to deviate more from its position before additional torque is applied to bring it back
	391
	392	The default value is zero and the effect becomes extreme by -4, +4. There are no units, only integers between -4 to 4. Greater values produce increasingly erratic behavior.
	393
31.1	394	Ex: #5AS-2<cr>
15.1	395
31.1	396	This reduces the angular stiffness to -2 for that session, allowing the servo to deviate more around the desired position. This can be beneficial in many situations such as impacts (legged robots) where more of a "spring" effect is desired. Upon reset, the servo will use the value stored in memory, based on the last configuration command.
15.1	397
31.1	398	Ex: #5QAS<cr>
15.1	399
	400	Queries the value being used.
	401
31.1	402	Ex: #5CAS<cr>
15.1	403
31.1	404	Writes the desired angular stiffness value to memory.
15.1	405
64.16	406	====== __15. Angular Hold Stiffness (AH)__ ======
15.1	407
62.1	408	The angular holding stiffness determines the servo's ability to hold a desired position under load. Values can be from -10 to 10, with the default being 0. Note that negative values mean the final position can be easily deflected.
15.1	409
62.1	410	Ex: #5AH3<cr>
	411
	412	This sets the holding stiffness for servo #5 to 3 for that session.
	413
	414	Query Angular Hold Stiffness (QAH)
	415
	416	Ex: #5QAH<cr> might return *5QAH3<cr>
	417
	418	This returns the servo's angular holding stiffness value.
	419
63.1	420	Configure Angular Hold Stiffness (CAH)
62.1	421
	422	Ex: #5CAH2<cr>
	423
	424	This writes the angular holding stiffness of servo #5 to 2 to EEPROM
	425
64.16	426	====== __15b: Angular Acceleration (AA)__ ======
63.1	427
	428	{More details to come}
	429
64.16	430	====== __15c: Angular Deceleration (AD)__ ======
63.1	431
	432	{More details to come}
	433
71.1	434	====== __15d: Motion Control (EM)__ ======
63.1	435
	436	{More details to come}
	437
64.16	438	====== __16. RGB LED (LED)__ ======
1.1	439
	440	Ex: #5LED3<cr>
	441
	442	This action sets the servo's RGB LED color for that session.The LED can be used for aesthetics, or (based on user code) to provide visual status updates. Using timing can create patterns.
	443
9.1	444	0=OFF 1=RED 2=GREEN 3= BLUE 4=YELLOW 5=CYAN 6= 7=MAGENTA, 8=WHITE
1.1	445
	446	Query LED Color (QLED)
	447
	448	Ex: #5QLED<cr> might return *5QLED5<cr>
	449
	450	This simple query returns the indicated servo's LED color.
	451
	452	Configure LED Color (CLED)
	453
35.1	454	Configuring the LED color via the CLED command sets the startup color of the servo after a reset or power cycle. Note that it also changes the session's LED color immediately as well.
1.1	455
83.1	456	====== __16b. Configure LED Blinking (CLB)__ ======
	457
90.1	458	This command allows you to control when the RGB LED will blink the user set color (see [[16. RGB LED>>\|\|anchor="H16.RGBLED28LED29"]] for details).
87.1	459	You can turn on or off blinking for various LSS status. Here is the list and their associated value: 0=No blinking, ; 63=Always blink; Blink while: 1=Limp; 2=Holding 4=Accel; 8=Decel; 16=Free 32=Travel;
83.1	460
85.1	461	To set blinking, use CLB with the value of your choosing. To activate blinking in multiple status, simply add together the values of the corresponding status. See examples below:
	462
	463	Ex: #5CLB0<cr> to turn off all blinking (LED always solid)
	464	Ex: #5CLB1<cr> only blink when limp
	465	Ex: #5CLB2<cr> only blink when holding
	466	Ex: #5CLB12<cr> only blink when accel or decel
	467	Ex: #5CLB48<cr> only blink when free or travel
	468	Ex: #5CLB63<cr> blink in all status
	469
64.16	470	====== __17. Identification Number__ ======
1.1	471
17.1	472	A servo's identification number cannot be set "on the fly" and must be configured via the CID command described below. The factory default ID number for all servos is 0. Since smart servos are intended to be daisy chained, in order to respond differently from one another, the user must set different identification numbers. Servos with the same ID and baud rate will all receive and react to the same commands.
1.1	473
	474	Query Identification (QID)
	475
38.1	476	EX: #254QID<cr> might return *QID5<cr>
1.1	477
38.1	478	When using the query ID command, it is best to only have one servo connected and thus receive only one reply using the broadcast command (ID 254). Alternatively, pushing the button upon startup and temporarily setting the servo ID to 255 will still result in the servo responding with its "real" ID.
1.1	479
	480	Configure ID (CID)
	481
38.1	482	Ex: #4CID5<cr>
1.1	483
	484	Setting a servo's ID in EEPROM is done via the CID command. All servos connected to the same serial bus will be assigned that ID. In most situations each servo must be set a unique ID, which means each servo must be connected individually to the serial bus and receive a unique CID number. It is best to do this before the servos are added to an assembly. Numbered stickers are provided to distinguish each servo after their ID is set, though you are free to use whatever alternative method you like.
	485
64.16	486	====== __18. Baud Rate__ ======
1.1	487
20.1	488	A servo's baud rate cannot be set "on the fly" and must be configured via the CB command described below. The factory default baud rate for all servos is 9600. Since smart servos are intended to be daisy chained, in order to respond to the same serial bus, all servos in that project should ideally be set to the same baud rate. Setting different baud rates will have the servos respond differently and may create issues. Available baud rates are: 9.6 kbps, 19.2 kbps, 38.4 kbps, 57.6 kbps, 115.2 kbps, 230.4 kbps, 250.0 kbps, 460.8 kbps, 500.0 kbps, 750.0 kbps, 921.6 kbps. Servos are shipped with a baud rate set to 9600. The baud rates are currently restricted to those above.
22.1	489	\*: Current tests reveal baud rates above 500 kbps are unstable and can cause timeouts. Please keep this in mind if using those / testing them out.
1.1	490
	491	Query Baud Rate (QB)
	492
	493	Ex: #5QB<cr> might return *5QB9600<cr>
	494
	495	Querying the baud rate is used simply to confirm the CB configuration command before the servo is power cycled.
	496
	497	Configure Baud Rate (CB)
	498
93.1	499	Important Note: the servo's current session retains the given baud rate and the new baud rate will only be in place when the servo is power cycled.
	500
1.1	501	Ex: #5CB9600<cr>
	502
	503	Sending this command will change the baud rate associated with servo ID 5 to 9600 bits per second.
	504
64.16	505	====== __19. Gyre Rotation Direction__ ======
1.1	506
	507	"Gyre" is defined as a circular course or motion. The effect of changing the gyre direction is as if you were to use a mirror image of a circle. CW = 1; CCW = -1. The factory default is clockwise (CW).
	508
	509	{images showing before and after with AR and Origin offset}
	510
	511	Query Gyre Direction (QG)
	512
	513	Ex: #5QG<cr> might return *5QG-1<cr>
	514
	515	The value returned above means the servo is in a counter-clockwise gyration.
	516
	517	Configure Gyre (CG)
	518
	519	Ex: #5CG-1<cr>
	520
	521	This changes the gyre direction as described above and also writes to EEPROM.
	522
64.16	523	====== __20. First / Initial Position (pulse)__ ======
1.1	524
49.1	525	In certain cases, a user might want to have the servo move to a specific angle upon power up. We refer to this as "first position". The factory default has no first position value stored in EEPROM and therefore upon power up, the servo remains limp until a position (or hold command) is assigned. FP and FD are different in that FP is used for RC mode only, whereas FD is used for smart mode only.
1.1	526
	527	Query First Position in Pulses (QFP)
	528
	529	Ex: #5QFP<cr> might return *5QFP1550<cr>
	530
36.1	531	The reply above indicates that servo with ID 5 has a first position pulse of 1550 microseconds. If no first position has been set, servo will respond with DIS ("disabled").
1.1	532
36.1	533	Configure First Position in Pulses (CFP)
1.1	534
	535	Ex: #5CP1550<cr>
	536
36.1	537	This configuration command means the servo, when set to RC mode, will immediately move to an angle equivalent to having received an RC pulse of 1550 microseconds upon power up. Sending a CFP command without a number results in the servo remaining limp upon power up (i.e. disabled).
1.1	538
64.16	539	====== __21. First / Initial Position (Degrees)__ ======
1.1	540
49.1	541	In certain cases, a user might want to have the servo move to a specific angle upon power up. We refer to this as "first position". The factory default has no first position value stored in EEPROM and therefore upon power up, the servo remains limp until a position (or hold command) is assigned. FP and FD are different in that FP is used for RC mode only, whereas FD is used for smart mode only.
1.1	542
	543	Query First Position in Degrees (QFD)
	544
	545	Ex: #5QFD<cr> might return *5QFD64<cr>
	546
	547	The reply above indicates that servo with ID 5 has a first position pulse of 1550 microseconds.
	548
	549	Configure First Position in Degrees (CFD)
	550
	551	Ex: #5CD64<cr>
	552
49.1	553	This configuration command means the servo, when set to smart mode, will immediately move to 6.4 degrees upon power up. Sending a CFD command without a number results in the servo remaining limp upon power up.
1.1	554
64.16	555	====== __22. Query Target Position in Degrees (QDT)__ ======
1.1	556
	557	Ex: #5QDT<cr> might return *5QDT6783<cr>
	558
	559	The query target position command returns the target angle during and after an action which results in a rotation of the servo horn. In the example above, the servo is rotating to a virtual position of 678.3 degrees. Should the servo not have a target position or be in wheel mode, it will respond without a number (Ex: *5QDT<cr>).
	560
64.16	561	====== __23. Query Model String (QMS)__ ======
1.1	562
64.1	563	Ex: #5QMS<cr> might return *5QMSLSS-HS1cr>
1.1	564
64.1	565	This reply means the servo model is LSS-HS1, meaning a high speed servo, first revision.
1.1	566
64.16	567	====== __23b. Query Model (QM)__ ======
64.1	568
	569	Ex: #5QM<cr> might return *5QM68702699520cr>
	570
	571	This reply means the servo model is 0xFFF000000 or 100, meaning a high speed servo, first revision.
	572
64.16	573	====== __24. Query Serial Number (QN)__ ======
1.1	574
	575	Ex: #5QN<cr> might return *5QN~_~_<cr>
	576
	577	The number in the response is the servo's serial number which is set and cannot be changed.
	578
64.16	579	====== __25. Query Firmware (QF)__ ======
1.1	580
	581	Ex: #5QF<cr> might return *5QF11<cr>
	582
	583	The integer in the reply represents the firmware version with one decimal, in this example being 1.1
	584
64.16	585	====== __26. Query Status (Q)__ ======
1.1	586
34.1	587	Ex: #5Q<cr> might return *5Q6<cr>, which indicates the motor is holding a position.
1.1	588
35.1	589	\|Value returned\|Status\|Detailed description*
34.1	590	\|ex: *5Q0<cr>\|Unknown\|LSS is unsure
	591	\|ex: *5Q1<cr>\|Limp\|Motor driving circuit is not powered and horn can be moved freely
	592	\|ex: *5Q2<cr>\|Free moving\|Motor driving circuit is not powered and horn can be moved freely
	593	\|ex: *5Q3<cr>\|Accelerating\|Increasing speed from rest (or previous speeD) towards travel speed
	594	\|ex: *5Q4<cr>\|Traveling\|Moving at a stable speed
69.1	595	\|ex: *5Q5<cr>\|Decelerating\|Decreasing from travel speed towards final position.
34.1	596	\|ex: *5Q6<cr>\|Holding\|Keeping current position
	597	\|ex: *5Q7<cr>\|Stepping\|Special low speed mode to maintain torque
69.1	598	\|ex: *5Q8<cr>\|Outside limits\|{More details coming soon}
34.1	599	\|ex: *5Q9<cr>\|Stuck\|Motor cannot perform request movement at current speed setting
69.1	600	\|ex: *5Q10<cr>\|Blocked\|Similar to stuck, but the motor is at maximum duty and still cannot move (i.e.: stalled)
1.1	601
64.16	602	====== __27. Query Voltage (QV)__ ======
1.1	603
59.1	604	Ex: #5QV<cr> might return *5QV11200<cr>
1.1	605
	606	The number returned has one decimal, so in the case above, servo with ID 5 has an input voltage of 11.2V (perhaps a three cell LiPo battery).
	607
64.16	608	====== __28. Query Temperature (QT)__ ======
1.1	609
	610	Ex: #5QT<cr> might return *5QT564<cr>
	611
	612	The units are in tenths of degrees Celcius, so in the example above, the servo's internal temperature is 56.4 degrees C. To convert from degrees Celcius to degrees Farenheit, multiply by 1.8 and add 32. Therefore 56.4C = 133.52F.
	613
64.16	614	====== __29. Query Current (QC)__ ======
1.1	615
	616	Ex: #5QC<cr> might return *5QC140<cr>
	617
	618	The units are in milliamps, so in the example above, the servo is consuming 140mA, or 0.14A.
	619
64.16	620	====== __30. RC Mode (CRC)__ ======
42.1	621
51.1	622	This command puts the servo into RC mode (position or continuous), where it will only respond to RC pulses. Note that because this is the case, the servo will no longer accept serial commands. The servo can be placed back into smart mode by using the button menu.
42.1	623
50.1	624	\|Command sent\|Note
	625	\|ex: #5CRC<cr>\|Stay in smart mode.
	626	\|ex: #5CRC1<cr>\|Change to RC position mode.
	627	\|ex: #5CRC2<cr>\|Change to RC continuous (wheel) mode.
52.2	628	\|ex: #5CRC<cr>\|Where is any number or value. Stay in smart mode.
50.1	629
42.1	630	EX: #5CRC<cr>
	631
64.16	632	====== __31. RESET__ ======
1.1	633
	634	Ex: #5RESET<cr> or #5RS<cr>
	635
	636	This command does a "soft reset" (no power cycle required) and reverts all commands to those stored in EEPROM (i.e. configuration commands).
	637
64.16	638	====== __32. DEFAULT & CONFIRM__ ======
1.1	639
	640	Ex: #5DEFAULT<cr>
	641
12.1	642	This command sets in motion the reset all values to the default values included with the version of the firmware installed on that servo. The servo then waits for the CONFIRM command. Any other command received will cause the servo to exit the DEFAULT function.
1.1	643
12.1	644	EX: #5DEFAULT<cr> followed by #5CONFIRM<cr>
1.1	645
12.1	646	Since it it not common to have to restore all configurations, a confirmation command is needed after a firmware command is sent. Should any command other than CONFIRM be received by the servo after the firmware command has been received, it will leave the firmware action.
1.1	647
13.1	648	Note that after the CONFIRM command is sent, the servo will automatically perform a RESET.
	649
64.16	650	====== __33. UPDATE & CONFIRM__ ======
1.1	651
12.1	652	Ex: #5UPDATE<cr>
1.1	653
12.1	654	This command sets in motion the equivalent of a long button press when the servo is not powered in order to enter firmware update mode. This is useful should the button be broken or inaccessible. The servo then waits for the CONFIRM command. Any other command received will cause the servo to exit the UPDATE function.
1.1	655
12.1	656	EX: #5UPDATE<cr> followed by #5CONFIRM<cr>
1.1	657
12.1	658	Since it it not common to have to update firmware, a confirmation command is needed after an UPDATE command is sent. Should any command other than CONFIRM be received by the servo after the firmware command has been received, it will leave the firmware action.
	659
13.1	660	Note that after the CONFIRM command is sent, the servo will automatically perform a RESET.

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