Pololu Maestro Manuale Utente

Pololu Maestro Servo ControllerUser's GuidePololu Maestro Servo Controller User's Guide © 2001–2014 Pololu Corporationhttp://www.pololu.com/

Mini Maestro 18-channel USB servo controller (fullyassembled) labeled top view.Mini Maestro 24-channel USB servo controller (fullyassembled) labeled t

Mini Maestro 12 power pins.Mini Maestro 18 power pins.Mini Maestro 24 power pins.The processor and the servos can have separate power supplies.Process

The RST pin can be driven low to reset the Maestro’s microcontroller, but this should not be necessary for typicalapplications. The line is internally

be controlled by the user script; the red LED will be on if there is an error or if the script command for turning iton was run.• The yellow status LE

2. Contacting PololuYou can check the product page of your particular Maestro model for additional information. We would be delightedto hear from you

3. Getting Started3.a. Installing Windows Drivers and SoftwareIf you are using Windows XP, you will need to have Service Pack 3 [http://www.microsoft.

7. On the second screen of the “Found New Hardware Wizard”, select “Install the software automatically” andclick “Next”.Pololu Maestro Servo Controlle

8. Windows XP will warn you again that the driver has not been tested by Microsoft and recommend that youstop the installation. Click “Continue Anyway

If you use Windows XP and experience problems installing or using the serial port drivers, the cause of your problemsmight be a bug in older versions

Windows 7 device manager showing the Micro Maestro 6-channel USB servo controller.Windows XP device manager showing the Micro Maestro 6-channel USB se

1. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3.b. Installing Linux Drivers and SoftwareThe Maestro Control Center running in Ubuntu Linux.You can download the Maestro Control Center and the Maest

• The 8-bit neutral point is 1500 μs and the 8-bit range is 476.25 μs.• On startup or error, the servos turn off (no pulses are sent).• On startup, th

4. Using the Maestro Control CenterThe Maestro’s USB interface provides access to all configuration options as well as support for real-time control,f

The PWM Output control in the Status tab in theMaestro Control Center (only available on theMini Maestro 12, 18, and 24).The “Speed” and “Acceleration

4.b. ErrorsThe Errors tab in the Maestro Control Center.The Errors tab indicates problems that the Maestro has detected while running, either communic

• Serial CRC error (bit 3)This error occurs when the Maestro is running in CRC-enabled mode and the cyclic redundancy check (CRC)byte at the end of th

4.c. SequencerThe Sequence tab in the Maestro Control Center.The Sequence tab allows simple motion sequences to be created and played back on the Maes

The Sequence dropdown box along with the Rename, Delete, and New Sequence buttons allow you to create andmanage multiple sequences.A sequence can also

4.d. Entering a ScriptThe Script tab in the Maestro Control Center.The Script tab is where you enter a script to be loaded into the Maestro. For detai

Examining the compiled codeClick the “View Compiled Code” button to see the actual bytes that are created by each line of your script. This isavailabl

1. OverviewThe Maestros are Pololu’s second-generation family ofUSB servo controllers. The Maestro family consists offour controllers, each available

• Output specifies that the channel should be used as a simple digital output. Instead of indicating a pulsewidth, the position value of the channel i

Period (T) Rate Speed units Acceleration unitsT = 20 ms 50 Hz (0.25 μs)/(10 ms) (0.25 μs)/(10 ms)/(80 ms)T = 3–19 ms > 50 Hz (0.25 μs)/T (0.25 μs)/

Upgrade InstructionsYou can determine the version of your Maestro’s firmware by running the Maestro Control Center, connecting toa Maestro, and lookin

14. It will take a few seconds to erase the Maestro’s existing firmware and load the new firmware. Do notdisconnect the Maestro during the upgrade.15.

Bootloader pads for the MiniMaestro 12-, 18-, or 24-ChannelUSB Servo Controller.3. While the pads are shorted together, connect the Maestro to USB. Us

5. Serial Interface5.a. Serial SettingsThe Maestro has three different serial interfaces. First, it has the TX and RX lines, which allow the Maestro t

The USB Dual Port serial mode.The USB Chained serial mode.The UART serial mode.The Maestro can be configured to be in one of three basic serial modes:

Mini SSC offset: This parameter determines which servo numbers the device will respond to in the Mini SSCprotocol (see Section 5.e).Timeout: This para

bytes per second is the baud rate divided by ten. At the Maestro’s maximum baud rate of 250,000 bits per second, themaximum realizable data rate, with

change. Any Maestro on the line whose device number matches the specified device number accepts the commandthat follows; all other Pololu devices igno

A USB A to mini-B cable [http://www.pololu.com/product/130] (not included) is required to connect this device to acomputer.Pololu Maestro Servo Contro

A detailed account of how cyclic redundancy checking works is beyond the scope of this document, but you can finda wealth of information using Wikiped

1 0 1 0 0 0 1 0 | | | | | |1 0 0 0 1 0 0 1 | | | | | |_______________ | | | | | |1 0 1 0 1 1 0 0 | | | |1 0 0 0 1 0 0 1 | | | |_______________ | | | |

for that channel. Specifically, an 8-bit target of 127 corresponds to the neutral setting for that channel, while 0 or 254correspond to the neutral se

acceleration limit. An acceleration limit causes the speed of a servo to slowly ramp up until it reaches the maximumspeed, then to ramp down again as

This command is used to determine whether the servo outputs have reached their targets or are still changing and willreturn 1 as long as there is at l

Restart Script at Subroutine with ParameterCompact protocol: 0xA8, subroutine number, parameter low bits, parameter high bitsPololu protocol: 0xAA, de

Daisy chaining serial devices that have a TXIN input.Using a PC and a Maestro together as the master deviceThe Maestro can enable a personal computer

detected the baud rate, Pololu devices that expect a leading command byte of 0x80 will ignore command packets thatstart with 0xAA, and the Maestro wil

//const char * device = "/dev/cu.usbmodem00034567"; // Mac OS Xint fd = open(device, O_RDWR | O_NOCTTY);if (fd == -1){perror(device);return

putc(0xAA);putc(0x0C);putc(0x04);putc(0x00);putc(0x70); // Target position = 1500 us (typical neutral for servos)putc(0x2E);delay_ms(1000);}}5.h.4. B

The Channel Settings tab in the MaestroControl Center.The Status tab in the Maestro ControlCenter.Features• Three control methods: USB, TTL (5 V) seri

6. The Maestro Scripting LanguageA script is a sequence of commands that is executed by the Maestro. Commands can set servo targets, speeds,and accele

1 3 miNUS4 # this is a comment!timeswith absolutely no effect on the compiled program. We generally use lower-case for commands and two or four spac

goto mylabel# ...any code here is skipped...4000 1 servomylabel: # the program continues here4000 2 servoIn this example, only servo 2 will get set to

KeywordskeywordstackeffectdescriptionBEGIN none marks the beginning of a loopENDIF none ends a conditional block IF…ENDIFELSE none begins the alternat

Stack commandscommandstackeffectdescriptionDEPTH +1 gets the number of numbers on the stackDROP -1 removes the top number from the stackDUP +1 duplica

command C equivalent descriptionBITWISE_AND & applies the boolean AND function to corresponding bits of the argumentsBITWISE_OR | applies the bool

Servo, LED, and other output commandscommandstackeffectdescriptionSPEED -2sets the speed of the channel specified by the top element to the value in t

led_on delayled_off delayrepeatThe numbers are placed on the stack at the beginning of the loop, then consumed later on in execution. Pay attentionto

Using the subroutine brings the script down to 31 bytes: 4 per position and 11 bytes of overhead for the loop andto define FRAME. We can go further: i

just 1.1 bytes per frame. We could store a sequence containing 900 different positions in the memory of the MicroMaestro using this kind of script.Mak

Maestro Comparison TableMicroMaestroMiniMaestro 12MiniMaestro 18MiniMaestro 24Channels: 6 12 18 24Analog input channels: 6 12 12 12Digital input chann

8000 # go to 8000 for values 600-1023endifendif0 servodrop # remove the original copy of the pot valuerepeatThe example above works, but when the

0 get_position 500 less_thanreturn# This subroutine uses the BUTTON subroutine above to wait for a button press,# including a small delay to eliminate

button_c if sequence_c endifrepeat# These subroutines each return 1 if the corresponding# button is pressed, and return 0 otherwise.# Currently button

Connecting the Micro Maestro to a chain ofShiftBars. A single 12V supply powers all of thedevices.repeatdrop return # remove the 0 from

Serial output (Mini Maestro 12, 18, and 24 only)On the Mini Maestro 12, 18, and 24, a script can be used to send serial data out on the TTL-level seri

The Micro Maestro’s processor can bepowered from USB while the servos arepowered by a separate supply.The Micro Maestro’s processor and servoscan be p

The Micro Maestro’s processor and servoscan be powered from a single 5–16V supplyif you connect the positive servo power railto VIN.One power supplyIf

Diagram for connecting a button orswitch to the Micro Maestro ServoController.Diagram for connecting apotentiometer to the Micro Maestroservo controll

Diagram for connecting an LED tothe Micro Maestro servo controller.Diagram showing how to connect theMicro Maestro servo controller to amicrocontrolle

The Pololu USB SDK contains example code forthe Maestro in C#, Visual C++, and Visual Basic.NET.8. Writing PC Software to Control the MaestroThere are

Micro Maestro as the brains of a tinyhexapod robot.Application Examples• Serial servo controller for multi-servo projects (e.g. robotarms, animatronic

9. Maestro Settings LimitationsMini Maestro serial baud rate limitationsOn the Mini Maestro 12, 18, and 24, the following baud rates should not be exc

Allowed pulse ranges at 333 Hz:Servos Min Max6 64 23286 192 264812 64 175212 384 24566/6 384/64 207218 64 117618 576 226424 768 2072Allowed pulse rang

10. Related ResourcesThis section lists resources that might help you use the Maestro. Please note that these resources are of varying qualityand most

Accessories• Pololu Maestro Case [http://www.thingiverse.com/thing:6876]: This is a 3D design on Thingiverse for a casedesigned to fit the Micro Maest

Micro Maestro power pins.Micro Maestro configured to usea single power supply for bothboard and servos.can also be used to send commands to the servo

Mini Maestro 12-channel USB servo controller (fullyassembled) labeled top view.Micro Maestro 6-channel USB servo controllerbottom view with quarter fo