Wiki source code of LSS - Communication Protocol

Version 52.1 by RB1 on 2018/09/10 17:03
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Coleman Benson 1.1 1 The Lynxmotion Smart Servo (LSS) protocol was created in order to be as simple and straightforward as possible from a user perspective, while at the same time trying to stay compact and robust yet highly versatile. Almost everything one might expect to be able to configure for a smart servo motor is available.
2
3 === Session ===
4
5 A "session" is defined as the time between when the servo is powered ON to when it is powered OFF or reset.
6
7 == Action Commands ==
8
9 Action commands are sent serially to the servo's Rx pin and must be set in the following format:
10
11 1. Start with a number sign # (U+0023)
12 1. Servo ID number as an integer
13 1. Action command (one to three letters, no spaces, capital or lower case)
14 1. Action value in the correct units with no decimal
15 1. End with a control / carriage return '<cr>'
16
17 (((
18 Ex: #5PD1443<cr>
19
20 Move servo with ID #5 to a position of 144.3 degrees.
21
22 Action commands cannot be combined with query commands, and only one action command can be sent at a time.
23
24 Action commands are session-specific, therefore once a servo is power cycled, it will not have any "memory" of previous actions or virtual positions (as described at the bottom of this page).
25
26 === Action Modifiers ===
27
28 Two commands can be used as action modifiers only: Timed Move and Speed. The format is:
29
30 1. Start with a number sign # (U+0023)
31 1. Servo ID number as an integer
32 1. Action command (one to three letters, no spaces, capital or lower case)
33 1. Action value in the correct units with no decimal
34 1. Modifier command (one letter)
35 1. Modifier value in the correct units with no decimal
36 1. End with a control / carriage return '<cr>'
37
38 Ex: #5P1456T1263<cr>
39
40 Results in the servo rotating from the current angular position to a pulse position of 1456 in 1263 milliseconds.
41
42 Modified commands are command specific.
43 )))
44
Coleman Benson 16.1 45 (((
46
47 )))
48
49 == Configuration Commands ==
50
Coleman Benson 41.1 51 Configuration commands affect the servo's current session* but unlike action commands, configuration commands are written to EEPROM and are retained even if the servo loses power (therefore NOT session specific). Not all action commands have a corresponding configuration and vice versa. Certain configurations are retained for when the servo is used in RC model. More information can be found on the [[LSS - RC PWM page>>doc:LSS - Overview (DEV).LSS - RC PWM.WebHome]].
Coleman Benson 16.1 52
53 1. Start with a number sign # (U+0023)
54 1. Servo ID number as an integer
55 1. Configuration command (two to three letters, no spaces, capital or lower case)
56 1. Configuration value in the correct units with no decimal
57 1. End with a control / carriage return '<cr>'
58
59 Ex: #5CO-50<cr>
60
61 Assigns an absolute origin offset of -5.0 degrees (with respect to factory origin) to servo #5 and changes the offset for that session to -5.0 degrees.
62
63 Configuration commands are not cumulative, in that if two configurations are sent at any time, only the last configuration is used and stored.
64
65 *Important Note: the one exception is the baud rate - the servo's current session retains the given baud rate. The new baud rate will only be in place when the servo is power cycled.
66
Coleman Benson 1.1 67 == Query Commands ==
68
69 Query commands are sent serially to the servo's Rx pin and must be set in the following format:
70
71 1. Start with a number sign # (U+0023)
72 1. Servo ID number as an integer
73 1. Query command (one to three letters, no spaces, capital or lower case)
74 1. End with a control / carriage return '<cr>'
75
76 (((
77 Ex: #5QD<cr>Query position in degrees for servo #5
78 )))
79
80 (((
81 The query will return a value via the Tx pin with the following format:
82
83 1. Start with an asterisk (U+002A)
84 1. Servo ID number as an integer
85 1. Query command (one to three letters, no spaces, capital letters)
86 1. The reported value in the units described, no decimals.
87 1. End with a control / carriage return '<cr>'
88
89 (((
90 Ex: *5QD1443<cr>
91 )))
92
93 Indicates that servo #5 is currently at 144.3 degrees.
94
Coleman Benson 16.1 95 **Session vs Configuration Query**
Coleman Benson 1.1 96
Coleman Benson 16.1 97 By default, the query command returns the sessions' value; should no action commands have been sent to change, it will return the value saved in EEPROM from the last configuration command.
Coleman Benson 1.1 98
Coleman Benson 16.1 99 In order to query the value in EEPROM, add a '1' to the query command.
Coleman Benson 1.1 100
Coleman Benson 16.1 101 Ex: #5CSR20<cr> sets the maximum speed for servo #5 to 20rpm upon RESET (explained below).
Coleman Benson 1.1 102
Coleman Benson 16.1 103 After RESET: #5SR4<cr> sets the session's speed to 4rpm.
Coleman Benson 1.1 104
Coleman Benson 16.1 105 #5QSR<cr> would return *5QSR4<cr> which represents the value for that session.
Coleman Benson 1.1 106
Coleman Benson 16.1 107 #5QSR1<cr> would return *5QSR20<cr> which represents the value in EEPROM
108 )))
Coleman Benson 1.1 109
110 = Command List =
111
112 |= #|=Description|= Action|= Query|= Config|= RC|= Serial|= Units|= Notes
113 | 1|**L**imp| L| | | | ✓| none|
114 | 2|**H**alt & Hold| H| | | | ✓| none|
115 | 3|**T**imed move| T| | | | ✓| milliseconds| Modifier only
116 | 4|**S**peed| S| | | | ✓| microseconds / second| Modifier only
117 | 5|**M**ove in **D**egrees (relative)| MD| | | | ✓| tenths of degrees (ex 325 = 32.5 degrees; 91 = 9.1 degrees)|
118 | 6|**O**rigin Offset| O| QO| CO| ✓| ✓| tenths of degrees (ex 325 = 32.5 degrees; 91 = 9.1 degrees)|
119 | 7|**A**ngular **R**ange| AR| QAR| CAR| ✓| ✓| tenths of degrees (ex 325 = 32.5 degrees; 91 = 9.1 degrees)|
RB1 10.1 120 | 8|Position in **P**ulse| P| QP| | | ✓| microseconds|(((
Coleman Benson 28.1 121 See details below
RB1 10.1 122 )))
Coleman Benson 1.1 123 | 9|Position in **D**egrees| D| QD| | | ✓| tenths of degrees (ex 325 = 32.5 degrees; 91 = 9.1 degrees)|
124 | 10|**W**heel mode in **D**egrees| WD| QWD| | | ✓| tenths of degrees per second (ex 248 = 24.8 degrees per second)|
125 | 11|**W**heel mode in **R**PM| WR| QWR| | | ✓| rpm|
Coleman Benson 45.1 126 | 12|Max **S**peed in **D**egrees| SD| QSD| CSD| ✓| ✓| tenths of degrees per second (ex 248 = 24.8 degrees per second)|QSD: Add modifier "2" for instantaneous speed
127 | 13|Max **S**peed in **R**PM| SR| QSR| CSR| ✓| ✓| rpm|QSR: Add modifier "2" for instantaneous speed
Coleman Benson 47.1 128 | 14|**A**ngular **S**tiffness| AS| QAS| CAS| ✓| ✓|none|-4 to +4, but suggested values are between 0 to +4
Coleman Benson 15.1 129 | 15|//N/A (removed)//| | | | | | |
Coleman Benson 44.1 130 | 16|**LED** Color| LED| QLED| CLED| ✓| ✓| none (integer from 1 to 8)|0=OFF 1=RED 2=GREEN 3= BLUE 4=YELLOW 5=CYAN 6=MAGENTA, 7=WHITE
Coleman Benson 28.1 131 | 17|**ID** #| ID| QID| CID| | ✓| none (integer from 0 to 250)|Note: ID 254 is a "broadcast" which all servos respond to
Coleman Benson 1.1 132 | 18|**B**aud rate| B| QB| CB| | ✓| none (integer)|
133 | 19|**G**yre direction (**G**)| G| QG| CG| ✓| ✓| none | Gyre / rotation direction where 1= CW (clockwise) -1 = CCW (counter-clockwise)
Coleman Benson 9.1 134 | 20|**F**irst Position (**P**ulse)| | QFP|CFP | ✓| ✓| none |
135 | 21|**F**irst Position (**D**egrees)| | QFD|CFD| ✓| ✓| none |
Coleman Benson 1.1 136 | 22|**T**arget (**D**egree) **P**osition| | QDT| | | ✓| tenths of degrees (ex 325 = 32.5 degrees; 91 = 9.1 degrees)|
137 | 23|**M**odel| | QM| | | | none (integer)|
138 | 24|Serial **N**umber| | QN| | | | none (integer)|
139 | 25|**F**irmware version| | QF| | | | none (integer)|
RB1 33.1 140 | 26|**Q**uery (general status)| | Q| | | ✓| none (integer from 1 to 8)| See command description for details
Coleman Benson 1.1 141 | 27|**V**oltage| | QV| | | ✓| tenths of volt (ex 113 = 11.3V; 92 = 9.2V)|
Coleman Benson 40.1 142 | 28|**T**emperature| | QT| | | ✓| degrees Celsius|Max temp before error: 85°C (servo goes limp)
Coleman Benson 1.1 143 | 29|**C**urrent| | QC| | | ✓| tenths of Amps (ex 2 = 0.2A)|
RB1 48.1 144 | 30|**RC** Mode| | |CRC| |✓| |(((
145 CRC: Add modifier "1" for RC-position mode.
146 CRC: Add modifier "2" for RC-wheel mode.
147 Any other value for the modifier results in staying in smart mode.
148 Puts the servo into RC mode. To revert to smart mode, use the button menu.
149 )))
Coleman Benson 9.1 150 | | | | | | | | |
Coleman Benson 1.1 151
152 = Details =
153
154 __1. Limp (**L**)__
155
156 Example: #5L<cr>
157
158 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>.
159
160 __2. Halt & Hold (**H**)__
161
162 Example: #5H<cr>
163
164 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.
165
166 __3. Timed move (**T**)__
167
168 Example: #5P1500T2500<cr>
169
170 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.
171
172 __4. Speed (**S**)__
173
174 Example: #5P1500S750<cr>
175
176 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.
177
178 __5. (Relative) Move in Degrees (**MD**)__
179
180 Example: #5MD123<cr>
181
182 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.
183
184 __6. Origin Offset Action (**O**)__
185
186 Example: #5O2400<cr>
187
188 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).
189
190 [[image:LSS-servo-default.jpg]]
191
192 In the second image, the origina, as well as the angular range (explained below) have been shifted by 240.0 degrees:
193
194 [[image:LSS-servo-origin.jpg]]
195
196 Origin Offset Query (**QO**)
197
198 Example: #5QO<cr> Returns: *5QO-13
199
200 This allows you to query the angle (in tenths of degrees) of the origin in relation to the factory zero position.
201
202 Configure Origin Offset (**CO**)
203
204 Example: #5CO-24<cr>
205
206 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.
207
208 __7. Angular Range (**AR**)__
209
210 Example: #5AR1800<cr>
211
212 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,
213
214 [[image:LSS-servo-default.jpg]]
215
216 Here, the angular range has been restricted to 180.0 degrees, or -90.0 to +90.0. The center has remained unchanged.
217
218 [[image:LSS-servo-ar.jpg]]
219
220 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:
221
222 [[image:LSS-servo-ar-o-1.jpg]]
223
224 Query Angular Range (**QAR**)
225
226 Example: #5QAR<cr> might return *5AR2756
227
228 Configure Angular Range (**CAR**)
229
230 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.
231
232 __8. Position in Pulse (**P**)__
233
234 Example: #5P2334<cr>
235
Coleman Benson 11.1 236 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.
Coleman Benson 1.1 237
238 Query Position in Pulse (**QP**)
239
Coleman Benson 37.1 240 Example: #5QP<cr> might return *5QP2334
Coleman Benson 1.1 241
Coleman Benson 11.1 242 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. 
Coleman Benson 37.1 243 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).
Coleman Benson 1.1 244
245 __9. Position in Degrees (**D**)__
246
247 Example: #5PD1456<cr>
248
249 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.
250
251 Larger values are permitted and allow for multi-turn functionality using the concept of virtual position.
252
253 Query Position in Degrees (**QD**)
254
Coleman Benson 37.1 255 Example: #5QD<cr> might return *5QD132<cr>
Coleman Benson 1.1 256
Coleman Benson 37.1 257 This means the servo is located at 13.2 degrees.
258
Coleman Benson 1.1 259 __10. Wheel Mode in Degrees (**WD**)__
260
261 Ex: #5WD900<cr>
262
263 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).
264
265 Query Wheel Mode in Degrees (**QWD**)
266
267 Ex: #5QWD<cr> might return *5QWD900<cr>
268
269 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).
270
271 __11. Wheel Mode in RPM (**WR**)__
272
273 Ex: #5WR40<cr>
274
275 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).
276
277 Query Wheel Mode in RPM (**QWR**)
278
279 Ex: #5QWR<cr> might return *5QWR40<cr>
280
281 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).
282
283 __12. Speed in Degrees (**SD**)__
284
285 Ex: #5SD1800<cr>
286
287 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.
288
289 Query Speed in Degrees (**QSD**)
290
291 Ex: #5QSD<cr> might return *5QSD1800<cr>
292
RB1 25.1 293 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.
RB1 23.1 294 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:
Coleman Benson 1.1 295
RB1 24.1 296 |**Command sent**|**Returned value (1/10 °)**
Coleman Benson 32.1 297 |ex: #5QSD<cr>|Session value for maximum speed (set by latest SD/SR command)
298 |ex: #5QSD1<cr>|Configured maximum speed  (set by CSD/CSR)
299 |ex: #5QSD2<cr>|Instantaneous speed (same as QWD)
300 |ex: #5QSD3<cr>|Target travel speed
RB1 23.1 301
Coleman Benson 1.1 302 Configure Speed in Degrees (**CSD**)
303
304 Ex: #5CSD1800<cr>
305
306 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.
307
308 __13. Speed in RPM (**SR**)__
309
310 Ex: #5SD45<cr>
311
312 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.
313
314 Query Speed in Degrees (**QSR**)
315
316 Ex: #5QSR<cr> might return *5QSR45<cr>
317
RB1 25.1 318 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.
319 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:
Coleman Benson 1.1 320
RB1 25.1 321 |**Command sent**|**Returned value (1/10 °)**
Coleman Benson 32.1 322 |ex: #5QSR<cr>|Session value for maximum speed (set by latest SD/SR command)
323 |ex: #5QSR1<cr>|Configured maximum speed  (set by CSD/CSR)
324 |ex: #5QSR2<cr>|Instantaneous speed (same as QWR)
325 |ex: #5QSR3<cr>|Target travel speed
Coleman Benson 1.1 326
RB1 25.1 327 Configure Speed in RPM (**CSR**)
328
Coleman Benson 1.1 329 Ex: #5CSR45<cr>
330
RB1 25.1 331 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.
Coleman Benson 1.1 332
Coleman Benson 31.1 333 __14. Angular Stiffness (AS)__
Coleman Benson 15.1 334
Coleman Benson 31.1 335 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.
Coleman Benson 15.1 336
Coleman Benson 31.1 337 A positive value of "angular stiffness":
Coleman Benson 15.1 338
339 * The more torque will be applied to try to keep the desired position against external input / changes
340 * The faster the motor will reach its intended travel speed and the motor will decelerate faster and nearer to its target position
341
342 A negative value on the other hand:
343
344 * Causes a slower acceleration to the travel speed, and a slower deceleration
345 * Allows the target position to deviate more from its position before additional torque is applied to bring it back
346
347 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.
348
Coleman Benson 31.1 349 Ex: #5AS-2<cr>
Coleman Benson 15.1 350
Coleman Benson 31.1 351 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.
Coleman Benson 15.1 352
Coleman Benson 31.1 353 Ex: #5QAS<cr>
Coleman Benson 15.1 354
355 Queries the value being used.
356
Coleman Benson 31.1 357 Ex: #5CAS<cr>
Coleman Benson 15.1 358
Coleman Benson 31.1 359 Writes the desired angular stiffness value to memory.
Coleman Benson 15.1 360
361 __15. N/A (removed)__
362
363 This command has been removed.
364
Coleman Benson 1.1 365 __16. RGB LED (**LED**)__
366
367 Ex: #5LED3<cr>
368
369 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.
370
Coleman Benson 9.1 371 0=OFF 1=RED 2=GREEN 3= BLUE 4=YELLOW 5=CYAN 6= 7=MAGENTA, 8=WHITE 
Coleman Benson 1.1 372
373 Query LED Color (**QLED**)
374
375 Ex: #5QLED<cr> might return *5QLED5<cr>
376
377 This simple query returns the indicated servo's LED color.
378
379 Configure LED Color (**CLED**)
380
Coleman Benson 35.1 381 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.
Coleman Benson 1.1 382
383 __17. Identification Number__
384
RB1 17.1 385 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.
Coleman Benson 1.1 386
387 Query Identification (**QID**)
388
Coleman Benson 38.1 389 EX: #254QID<cr> might return *QID5<cr>
Coleman Benson 1.1 390
Coleman Benson 38.1 391 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.
Coleman Benson 1.1 392
393 Configure ID (**CID**)
394
Coleman Benson 38.1 395 Ex: #4CID5<cr>
Coleman Benson 1.1 396
397 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.
398
399 __18. Baud Rate__
400
RB1 20.1 401 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.
RB1 22.1 402 \*: 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.
Coleman Benson 1.1 403
404 Query Baud Rate (**QB**)
405
406 Ex: #5QB<cr> might return *5QB9600<cr>
407
408 Querying the baud rate is used simply to confirm the CB configuration command before the servo is power cycled.
409
410 Configure Baud Rate (**CB**)
411
412 Ex: #5CB9600<cr>
413
414 Sending this command will change the baud rate associated with servo ID 5 to 9600 bits per second.
415
416 __19. Gyre Rotation Direction__
417
418 "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).
419
420 {images showing before and after with AR and Origin offset}
421
422 Query Gyre Direction (**QG**)
423
424 Ex: #5QG<cr> might return *5QG-1<cr>
425
426 The value returned above means the servo is in a counter-clockwise gyration.
427
428 Configure Gyre (**CG**)
429
430 Ex: #5CG-1<cr>
431
432 This changes the gyre direction as described above and also writes to EEPROM.
433
434 __20. First / Initial Position (pulse)__
435
RB1 49.1 436 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.
Coleman Benson 1.1 437
438 Query First Position in Pulses (**QFP**)
439
440 Ex: #5QFP<cr> might return *5QFP1550<cr>
441
Coleman Benson 36.1 442 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").
Coleman Benson 1.1 443
Coleman Benson 36.1 444 Configure First Position in Pulses (**CFP**)
Coleman Benson 1.1 445
446 Ex: #5CP1550<cr>
447
Coleman Benson 36.1 448 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).
Coleman Benson 1.1 449
450 __21. First / Initial Position (Degrees)__
451
RB1 49.1 452 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.
Coleman Benson 1.1 453
454 Query First Position in Degrees (**QFD**)
455
456 Ex: #5QFD<cr> might return *5QFD64<cr>
457
458 The reply above indicates that servo with ID 5 has a first position pulse of 1550 microseconds.
459
460 Configure First Position in Degrees (**CFD**)
461
462 Ex: #5CD64<cr>
463
RB1 49.1 464 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.
Coleman Benson 1.1 465
466 __22. Query Target Position in Degrees (**QDT**)__
467
468 Ex: #5QDT<cr> might return *5QDT6783<cr>
469
470 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>).
471
472 __23. Query Model (**QM**)__
473
474 Ex: #5QM<cr> might return *5QM11<cr>
475
476 This reply means the servo model is 1.1, meaning high speed servo, first revision. 1=HS (high speed) 2=ST (standard) 3=HT (high torque)
477
478 __24. Query Serial Number (**QN**)__
479
480 Ex: #5QN<cr> might return *5QN~_~_<cr>
481
482 The number in the response is the servo's serial number which is set and cannot be changed.
483
484 __25. Query Firmware (**QF**)__
485
486 Ex: #5QF<cr> might return *5QF11<cr>
487
488 The integer in the reply represents the firmware version with one decimal, in this example being 1.1
489
490 __26. Query Status (**Q**)__
491
RB1 34.1 492 Ex: #5Q<cr> might return *5Q6<cr>, which indicates the motor is holding a position.
Coleman Benson 1.1 493
Coleman Benson 35.1 494 |*Value returned|**Status**|**Detailed description**
RB1 34.1 495 |ex: *5Q0<cr>|Unknown|LSS is unsure
496 |ex: *5Q1<cr>|Limp|Motor driving circuit is not powered and horn can be moved freely
497 |ex: *5Q2<cr>|Free moving|Motor driving circuit is not powered and horn can be moved freely
498 |ex: *5Q3<cr>|Accelerating|Increasing speed from rest (or previous speeD) towards travel speed
499 |ex: *5Q4<cr>|Traveling|Moving at a stable speed
500 |ex: *5Q5<cr>|Deccelerating|Decreasing speed towards travel speed towards rest
501 |ex: *5Q6<cr>|Holding|Keeping current position
502 |ex: *5Q7<cr>|Stepping|Special low speed mode to maintain torque
503 |ex: *5Q8<cr>|Outside limits|More details coming soon
504 |ex: *5Q9<cr>|Stuck|Motor cannot perform request movement at current speed setting
505 |ex: *5Q10<cr>|Blocked|Similar to stuck, but the motor is at maxiumum duty and still cannot move (i.e.: stalled)
Coleman Benson 1.1 506
507 __27. Query Voltage (**QV**)__
508
509 Ex: #5QV<cr> might return *5QV112<cr>
510
511 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).
512
513 __28. Query Temperature (**QT**)__
514
515 Ex: #5QT<cr> might return *5QT564<cr>
516
517 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.
518
Coleman Benson 42.1 519 __29. Query Current (**QC**)__
Coleman Benson 1.1 520
521 Ex: #5QC<cr> might return *5QC140<cr>
522
523 The units are in milliamps, so in the example above, the servo is consuming 140mA, or 0.14A.
524
RB1 50.1 525 __30. RC Mode (**CRC**)__
Coleman Benson 42.1 526
RB1 51.1 527 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.
Coleman Benson 42.1 528
RB1 50.1 529 |**Command sent**|**Note**
530 |ex: #5CRC<cr>|Stay in smart mode.
531 |ex: #5CRC1<cr>|Change to RC position mode.
532 |ex: #5CRC2<cr>|Change to RC continuous (wheel) mode.
RB1 52.1 533 |ex: #5CRC*<cr>****|Where * is any number or value. Stay in smart mode.
RB1 50.1 534
Coleman Benson 42.1 535 EX: #5CRC<cr>
536
Coleman Benson 1.1 537 __**RESET**__
538
539 Ex: #5RESET<cr> or #5RS<cr>
540
541 This command does a "soft reset" (no power cycle required) and reverts all commands to those stored in EEPROM (i.e. configuration commands).
542
Coleman Benson 12.1 543 **__DEFAULT __**__& **CONFIRM**__
Coleman Benson 1.1 544
545 Ex: #5DEFAULT<cr>
546
Coleman Benson 12.1 547 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.
Coleman Benson 1.1 548
Coleman Benson 12.1 549 EX: #5DEFAULT<cr> followed by #5CONFIRM<cr>
Coleman Benson 1.1 550
Coleman Benson 12.1 551 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.
Coleman Benson 1.1 552
Coleman Benson 13.1 553 Note that after the CONFIRM command is sent, the servo will automatically perform a RESET.
554
Coleman Benson 12.1 555 **__UPDATE __**__& **CONFIRM**__
Coleman Benson 1.1 556
Coleman Benson 12.1 557 Ex: #5UPDATE<cr>
Coleman Benson 1.1 558
Coleman Benson 12.1 559 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.
Coleman Benson 1.1 560
Coleman Benson 12.1 561 EX: #5UPDATE<cr> followed by #5CONFIRM<cr>
Coleman Benson 1.1 562
Coleman Benson 12.1 563 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.
564
Coleman Benson 13.1 565 Note that after the CONFIRM command is sent, the servo will automatically perform a RESET.
566
Coleman Benson 1.1 567 === Virtual Angular Position ===
568
569 {In progress}
570
571 A "virtual position" is one which allows for multiple rotations of the output horn, moving the center position and more. The "absolute position" would be the angle of the output shaft with respect to 360.0 degrees.
572
573 [[image:LSS-servo-positions.jpg]]
574
575 Example: Gyre direction / rotation is positive (clockwise), and origin offset has not been modified.
576
577 #1D-300<cr> The servo is commander to move to -30.0 degrees (green arrow)
578
579 #1D2100<cr> This second position command is sent to the servo, which moves it to 210.0 degrees (orange arrow)
580
581 #1D-4200<cr> The servo rotates counterclockwise to a position of -420 degrees (red arrow), which means one full rotation of 360 degrees and (420.0-360.0) stopping at an absolute position of 60.0 degrees, but virtual position of -420.0.
582
583 Although the final position would be the same as if the servo were commanded to move to -60.0 degrees, it is in fact at -420.0 degrees.
584
585 #1D4800<cr> This new command is sent which would then cause the servo to rotate from -420.0 degrees to 480.0 degrees, which would be a total of 900 degrees of clockwise rotation, or 2.5 complete rotations.
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