T-Series/Compilation/Commands for motion products

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[edit] Detailed Command Reference

The version of firmware installed on any Zaber T-Series device can be determined by issuing command #51. A three-digit number will be returned. Assume 2 decimal places (ex a reply of 293 indicates firmware version 2.93). This command reference applies only to firmware version 5.00 and up (the most recent version). For earlier versions of firmware, please consult the appropriate PDF user's manual:

T-Series Manual 2xx (PDF)

T-Series Manual 4xx (PDF)

Due to the addition of new features, newer versions of firmware may not be 100% backward compatible. You may wish to read the document Firmware History and Migration which outlines the changes that have taken place from one firmware version to the next and indicates what options are available if you wish to upgrade or downgrade the firmware on your devices.

[edit] Reset - Cmd 0

Instruction Name	Reset
Firmware Version	5.00 and up
Command Number	0
Command Type	Command
Command Data	Ignored
Reply Data	None
Persistence	n/a
Summary	Sets the device to its power-up condition.

This has the same effect as unplugging and restarting the device.

[edit] Special Note

The position stored in the device prior to this command will be lost, so you must save it and reload it if it is important. All non-volatile settings (i.e. Device Number, Target Velocity, etc.) are saved and are not affected by reset or power-down.

[edit] Home - Cmd 1

Instruction Name	Home
Firmware Version	5.00 and up
Command Number	1
Command Type	Command
Command Data	Ignored
Reply Data	Final Position
Persistence	n/a
Summary	Causes a motion control device to back up to the home position and reset its internal position to 0.

Upon receiving this instruction, a motion control device will retract until its internal home sensor triggers. It will then move forward several steps to avoid accidentally re-triggering the home sensor during use. If a home offset has been specified with the Set Home Offset (command #47) instruction, the device will extend the additional distance specified. It will then stop and reset its internal position register, effectively setting the final position to 0.

[edit] Renumber - Cmd 2

Instruction Name	Renumber
Firmware Version	5.00 and up
Command Number	2
Command Type	Command
Command Data	New Number
Reply Data	Device Id
Persistence	Non-Volatile
Summary	Assigns new numbers to all the devices in the order in which they are connected.

If sent to device number 0, the command data is ignored and all devices will renumber. The device closest to the computer becomes device number 1. The next device becomes number 2 and so forth. If sent to a device number other than 0, then specified device will reassign itself the device number in the command data. Renumbering takes about 1/2 a second during which time the computer must not send any further data. The device number is stored in non-volatile memory so you can renumber once and not worry about issuing the renumber instruction again after each power-up.

[edit] Store Current Position - Cmd 16

Instruction Name	Store Current Position
Firmware Version	5.04 and up
Command Number	16
Command Type	Command
Command Data	Address
Reply Data	Address
Persistence	Non-Volatile
Summary	Saves the current absolute position of the device.

Valid Address values are 0 through 15 specifying one of 16 possible registers in which to store the position. This command can only be executed when the device has been homed. This command is used in conjunction with the Return Stored Position (Command #17) and Move To Stored Position (Command #18) instructions. The positions stored in the position registers are non-volatile and will persist after power-down or reset. All position registers are cleared by the Restore Settings (Command #36) instruction.

[edit] Return Stored Position - Cmd 17

Instruction Name	Return Stored Position
Firmware Version	5.04 and up
Command Number	17
Command Type	Command
Command Data	Address
Reply Data	Stored Position
Persistence	n/a
Summary	Returns the position stored in one of the 16 position registers for the device.

Valid address values are 0 through 15, specifying one of 16 possible registers from which to retrieve the position. This command is used in conjunction with the Store Current Position (#16) and Move To Stored Position (#18) commands. Positions stored in the position registers are non-volatile and will persist after power-down or reset. All position registers are cleared by the Restore Factory Settings (#36) command.

[edit] Move To Stored Position - Cmd 18

Instruction Name	Move To Stored Position
Firmware Version	5.04 and up
Command Number	18
Command Type	Command
Command Data	Address
Reply Data	Final Position
Persistence	n/a
Summary	Moves the device to the stored position specified by the Command Data.

Valid address values are 0 through 15, specifying one of 16 possible positions. This command is used in conjunction with the Store Current Position (#16) and Return Stored Position (#17) commands. All move commands are pre-emptive. If a new move command is issued before the previous move command is finished, the device will immediately move to the new position. The target speed and acceleration during a move can be specified using commands 42 and 43 respectively. This command may pre-empt, or be pre-empted by commands 18, 20, 21, 22 and 23.

[edit] Move Absolute - Cmd 20

Instruction Name	Move Absolute
Firmware Version	5.00 and up
Command Number	20
Command Type	Command
Command Data	Absolute Position
Reply Data	Final position
Persistence	n/a
Summary	Moves the device to the position specified in the Command Data in microsteps.

The position must be within the acceptable range for the device or an error code will be returned. All move commands are pre-emptive. If a new move command is issued before the previous move command is finished, the device will immediately move to the new position. The target speed and acceleration during a move absolute instruction can be specified using commands 42 and 43 respectively.

Command may pre-empt, or be pre-empted by commands 18, 20, 21, 22 and 23.

[edit] Move Relative - Cmd 21

Instruction Name	Move Relative
Firmware Version	5.00 and up
Command Number	21
Command Type	Command
Command Data	Relative Position
Reply Data	Final Position
Persistence	n/a
Summary	Moves the device by the positive or negative number of microsteps specified in the Command Data.

The device moves to the position given by its position before the command plus the value in command data. The final position must be within the acceptable range for the device or an error code will be returned. All move commands are pre-emptive. If a move relative command is issued while the device is currently moving due to a previous command, the device will immediately set a new target position equal to the current position (at the instant the command was received) plus the specified relative position. The target speed and acceleration during a move relative instruction can be specified using commands 42 and 43 respectively. The relative move command data (in microsteps) can be negative.

This command may pre-empt, or be pre-empted by commands 18, 20, 21, 22 and 23.

[edit] Move At Constant Speed - Cmd 22

Instruction Name	Move At Constant Speed
Firmware Version	5.00 and up
Command Number	22
Command Type	Command
Command Data	Speed
Reply Data	Speed
Persistence	n/a
Summary	Moves the device at a constant speed based on the value specified in the Command Data.

This instruction specifies a direction and a speed to move, rather than a target position. When this instruction is issued the device will accelerate (at a rate determined by command #43 Set Acceleration) to the speed specified by the instruction data. The device will continue moving at this speed until a limit is reached or a pre-empting instruction is issued. Negative speeds cause retraction while positive speeds cause extension.

To determine the actual speed that will result from a given data value, the following formulas may be used:

Actual Speed

= 9.375*(Command Data) [microsteps/sec] or

= 9.375*(Command Data)/R [steps/sec] or

= 562.5*(Command Data)/(R*S) [revolutions/min]

Where:

• Command Data is the absolute value of the Constant Speed Move instruction data
• R (microsteps/step) is the microstep resolution (command 37)
• S (steps/revolution) is the number of steps per revolution of the motor

For example, if S = 48, R = 64, and the Constant Speed Move instruction is issued with Data of 2922, then the device will move forward at a speed of approximately 535 revolutions per minute. For linear devices consult the section on Device Specific Information to determine the linear distance corresponding to a single step or revolution.

The maximum Data allowable is 512*R. Note that although the maximum data allowable depends on the resolution, the maximum speed possible is independent of the resolution. This can be seen by substituting Data = 512*R into the second formula above, giving a maximum speed (regardless of resolution) of 4800 steps/sec.

The device may be set to return its position continuously during the move using the set mode command (#40) bit 4. Position tracking is a reply-only command #8. If the device runs into zero position or maximum range, the device stops and the new position is returned via reply-only command #9.

This command may pre-empt, or be pre-empted by commands 18, 20, 21, 22 and 23.

[edit] Stop - Cmd 23

Instruction Name	Stop
Firmware Version	5.00 and up
Command Number	23
Command Type	Command
Command Data	Ignored
Reply Data	Final Position
Persistence	n/a
Summary	Stops the device from moving by preempting any move instruction.

This instruction can be used to pre-empt any move instruction. The device will decelerate (at a rate determined by command #43 Set Acceleration) and stop. The reply data is the current absolute position.

This command may pre-empt, or be pre-empted by commands 18, 20, 21, and 22.

[edit] Read Or Write Memory - Cmd 35

Instruction Name	Read Or Write Memory
Firmware Version	5.00 and up
Command Number	35
Command Type	Command
Command Data	Data
Reply Data	Data
Persistence	Non-Volatile
Summary	Reads or writes a byte of non-volatile memory.

128 bytes of memory are available for user data. For example, the user may want to save some custom data such as a serial number, a name string, or data that uniquely identifies a particular device. Data written is not cleared by power down or reset. The most significant bit of byte 3 specifies whether the instruction is a read (0) or a write (1). The least significant 7 bits of byte 3 specify the address to read/write (0 to 127). Byte 4 specifies the value to be written. Bytes 5 and 6 are ignored.

These settings are stored in non-volatile memory and will persist after power-down or reset.

[edit] Restore Settings - Cmd 36

Instruction Name	Restore Settings
Firmware Version	5.00 and up
Command Number	36
Command Type	Command
Command Data	Peripheral Id
Reply Data	Peripheral Id
Persistence	Non-Volatile
Summary	Restores the device settings to the factory defaults.

This command should be issued with a Peripheral Id of 0 to return the device to factory default settings. This instruction is very useful for troubleshooting. If the device does not appear to function properly, it may be because some of the settings have been changed. This instruction will restore the settings to default values. For a table of default settings, see Appendix A. All settings affected by this instruction are stored in non-volatile memory and will persist after power-down or reset.

[edit] Set Microstep Resolution - Cmd 37

Instruction Name	Set Microstep Resolution
Firmware Version	5.00 and up
Command Number	37
Command Type	Setting
Command Data	Microsteps
Reply Data	Microsteps
Persistence	Non-Volatile
Summary	Changes the number of microsteps per step.

Valid data are 1, 2, 4, 8, 16, 32, 64, and 128. The default on most devices is 64. All position data sent to or received from T-Series products is in units of microsteps. Note that when you change the microstep resolution using this command, other position related settings are changed automatically to adjust for the new microstep size. The table below gives an example showing how other settings are affected when the microstep resolution is changed from 128 to 64:

Setting	Before	After
Target Speed *	2922	1461
Maximum Travel Range *	280000	140000
Current Position	10501 **	5250 **
Maximum Relative Move *	20000	10000
Home Offset *	1000	500
Acceleration *	100	50

* The settings for these commands are saved in non-volatile memory, i.e. the settings persist even if the device is powered down. To restore all non-volatile settings to factory default, use Restore Settings (command 36).

** Note that if a number is divided by two, it is rounded down to the nearest whole number. The only exception to this is if acceleration would become 0 (because 0 for acceleration indicates infinite acceleration). If acceleration would become 0, it will instead be set to 1 which is the lowest acceleration possible.

[edit] Set Running Current - Cmd 38

Instruction Name	Set Running Current
Firmware Version	5.00 and up
Command Number	38
Command Type	Setting
Command Data	Value
Reply Data	Value
Persistence	Non-Volatile
Summary	Places a current limit on the device.

The current is related to the data by the formula:

RunningCurrent = CurrentCapacity*10/CommandData

The Command Data can be either 0 (no current) or 10 (maximum current) through 127 (minimum current). Note that values of 1 through 9 are not accepted. CurrentCapacity is the hardware’s maximum capability of output current. In other words, as a fraction of the maximum current the device is capable of, the running current will be 10/CommandData.

[edit] Special Note

Most devices limit the voltage rather than the current. In this case you can think of the CurrentCapacity as the power supply voltage and the RunningCurrent as the effective voltage being applied to the motor. For example, if a product uses a 5V motor and has a 15V power supply, the running current might be set as follows:

Command Data

= 10 * CurrentCapacity / RunningCurrent

= 10 * 15V / 5V

= 30

If your application does not require high torque, it is best to decrease the RunningCurrent to reduce power consumption, vibration, and motor heating. Trial and error should suggest an appropriate setting. If higher torque is required, it is generally safe to overdrive motors as long as they are not operated continuously. Motor temperature is typically the best indication of the degree to which overdriving can be employed. If the motor gets too hot to touch (>75°C), you should reduce the running current.

[edit] Set Hold Current - Cmd 39

Instruction Name	Set Hold Current
Firmware Version	5.00 and up
Command Number	39
Command Type	Setting
Command Data	Value
Reply Data	Value
Persistence	Non-Volatile
Summary	Sets the desired current to be used when the device is holding its position.

The formula for the hold current works the same way as for running current:

HoldCurrent = CurrentCapacity * 10 / CommandData

It is typical to run stepper motors at their rated current only during moves (for highest torque) and reduce the current when idle just to hold the position.

The range of accepted values is 10 - 127 (and 0). Typically the hold current can be set to around 25 - 50% of the running current. If the running current is set to a value of 24, the hold current may be set to a value of 48 to provide 50% hold. In some applications, the friction of the drive system alone is sufficient to hold the microstep position of the motor, and the hold current can be turned off completely. The hold current can be turned off by issuing the "Set Hold Current" instruction with data of 0.

When the device is moving, it applies running current to the motor. When the device stops moving, running current is applied for an additional 0.1 second before hold current is applied.

[edit] Set Device Mode - Cmd 40

Instruction Name	Set Device Mode
Firmware Version	5.04 and up
Command Number	40
Command Type	Setting
Command Data	Mode
Reply Data	Mode
Persistence	Non-Volatile
Summary	Sets the Mode for the given device.

[edit] Special Note

This command allows setting several options. Each option is controlled by a single bit within the command data. Most software you will encounter, including most of our demo software, represents all 4 data bytes as a single decimal value rather than specifying each bit individually. To determine what decimal value to use requires a basic understanding of how the data is represented in binary. The command data may be considered as a single 32-bit binary value. The least significant bit is bit_0, the next is bit_1, the next is bit_2, and so on up to the most significant bit_31. Each bit may have a value of either 1 or 0.

The corresponding decimal representation of this 32-bit data is given by:

Decimal value = (bit_0 * 1) + (bit_1 * 2) + … + (bit_n * 2^n) + … + (bit_31 * 2^31)

Each bit controls a single mode option as described in the table below. To determine the data value to use with the Set Device Mode command, simply determine the desired value of each bit (1 or 0), and calculate the decimal value using the above formula. Note that not all 32 bits are currently used. Any unused or reserved bits should be left as 0.

For example, suppose you want all mode bits to be 0 except for bit_3 (disable potentiometer), bit_14 (disable power LED), and bit_15 (disable serial LED). The Set Device Mode instruction should be sent with data calculated as follows:

Command Data

= 2^23 + 2^214 + 2^215

= 8 + 16384 + 32768

= 49160

Note that each instance of the Set Device Mode command overwrites ALL previous mode bits. Repeated commands do not have a cumulative effect. For example, suppose you send a Set Device Mode command with data of 8 to disable the potentiometer. If you then send another Set Device Mode command with data of 16384 to disable the power LED, you will re-enable the potentiometer since bit_3 in the 2nd instruction is 0.

Most devices have a default mode setting of 0 (all bits are 0), however, there are some exceptions. See Appendix A of the user manual for a table of default settings.

*Anti-backlash and Anti-sticktion routines are designed to compensate for backlash and sticktion. The solution to backlash is to always approach a position from the same direction. The solution to sticktion is to move the device far enough away from the final position to break free of sticktion before attempting the final move. The operation of the two features are dependent on each other, and the interaction of enabling one or both of the features is described in the diagram to the right.

For each setting scenario, the starting position is denoted by the solid vertical line and the final position is denoted by the dotted vertical line. There are four possible moves for each scenario: long move positive, long move negative, short move positive and short move negative. The arrows show the path that would be traversed for each scenario.

[edit] Set Target Speed - Cmd 42

Instruction Name	Set Target Speed
Firmware Version	5.00 and up
Command Number	42
Command Type	Setting
Command Data	Speed
Reply Data	Speed
Persistence	Non-Volatile
Summary	Sets the speed at which the device moves when using the "Move Absolute" or "Move Relative" commands.

When a move absolute or move relative instruction is issued, the device will accelerate at a rate determined by the acceleration setting up to a maximum speed determined by this command, “Set Target Speed". To determine the actual speed that will result from a given data value, the following formulas may be used:

Actual Speed

= 9.375*Data [microsteps/sec] or

= 9.375*Data/R [steps/sec] or

= 562.5*Data/(R x S) [revolutions/min]

Where:

• "Data" is the value of the Set Target Speed command data
• R (microsteps/step) is the microstep resolution (command 37)
• S (steps/revolution) is the number of steps per revolution of the motor

For example, if S = 48, R = 64, and the Constant Speed Move instruction is issued with Data of 2922, then the device will move forward at a speed of approximately 535 revolutions per minute. For linear devices consult the section on Device Specific Information to determine the linear distance corresponding to a single step or revolution.

Valid data values are from 0 to (512*R-1). Note that although the maximum data allowable depends on the resolution, the maximum speed possible is independent of the resolution. This can be seen by substituting Data = 512*R into the second formula above, giving a maximum speed (regardless of resolution) of 4800 steps/sec.

The target velocity may be changed on-the-fly even when the device is in the middle of a move. The device will automatically adjust the velocity, but still target the final position specified in the original move.

[edit] Set Acceleration - Cmd 43

Instruction Name	Set Acceleration
Firmware Version	5.00 and up
Command Number	43
Command Type	Setting
Command Data	Acceleration
Reply Data	Acceleration
Persistence	Non-Volatile
Summary	Sets the acceleration used by the movement commands.

When a movement command is issued, the device will accelerate at a rate determined by this command "Set Acceleration" up to a maximum speed determined by the target velocity. To determine the acceleration that will result from a given data value, the following formulas may be used:

Actual Acceleration

= 11250*(Command Data) [microsteps/sec^2]

= 11250*(CommandData/R) [steps/sec^2]

Where:

• "Command Data" is the value specified in the Command Data by the user
• R is the microstep resolution set in command #37(microsteps/step)

The maximum value allowable is (512*R-1). This is the same as the maximum allowable data for velocity, which means that the device will reach maximum velocity immediately. If acceleration is set to 0, it is as if acceleration is set to (512*R-1). Effectively acceleration is turned off and the device will start moving at the target speed immediately.

The acceleration may be changed on-the-fly even when the device is in the middle of a move. The device will still target the final position specified in the original move.

[edit] Set Maximum Range - Cmd 44

Instruction Name	Set Maximum Range
Firmware Version	5.00 and up
Command Number	44
Command Type	Setting
Command Data	Range
Reply Data	Range
Persistence	Non-Volatile
Summary	Sets a limit on the range of travel up to 16777216.

Use this command to limit the range of travel to a value other than the default. Exercise caution since using this command it is possible to set the range to a value greater than the physical limits of the device. The maximum range you can set is 16777216 microsteps.

This setting is stored in non-volatile memory and will persist after power-down or reset.

[edit] Set Current Position - Cmd 45

Instruction Name	Set Current Position
Firmware Version	5.00 and up
Command Number	45
Command Type	Setting
Command Data	New Position
Reply Data	New Position
Persistence	Volatile
Summary	Sets the the internal register that holds the position to the value specified in the command data.

The phase of the stepper motor is controlled by the least significant byte of the position, thus the device may move by +/- 2 full steps unless the new position corresponds to the true current position of the device. This command is useful if you want to turn off the system without losing position. Simply save the position in the controlling computer and turn off the hold current before powering down. After powering up, set the position back to the saved value and turn on the hold current. In this way you can continue without having to home the device. You have to turn off the hold current because when the power first comes on the position will default to the maximum range, and that may be out of phase with the motor's current position. If the hold current is on, it will force the motor into phase with the default position before you've had a chance to restore the current position.

The position data is volatile and will not persist after power-down or reset.

[edit] Set Maximum Relative Move - Cmd 46

Instruction Name	Set Maximum Relative Move
Firmware Version	5.00 and up
Command Number	46
Command Type	Setting
Command Data	Range
Reply Data	Range
Persistence	Non-volatile
Summary	Sets a limit on the number of microsteps the device can make for a Relative Move command.

Use this command to limit the maximum range of travel for a relative move command. For example, if maximum relative move is set to 1000, and the user requests a relative move (#21) of 800, then the device will move 800 microsteps. However, if the user requests a relative move of 1200, then the device will reply with an error code. Most applications can leave this unchanged from the default.

This setting is stored in non-volatile memory and will persist after power-down or reset.

[edit] Set Home Offset - Cmd 47

Instruction Name	Set Home Offset
Firmware Version	5.00 and up
Command Number	47
Command Type	Setting
Command Data	Offset
Reply Data	Offset
Persistence	Non-Volatile
Summary	Sets the the new "Home" position which can then be used when the Home command is issued.

When the home command is issued, the device will retract until the home sensor is triggered, then move forward until the home sensor is no longer triggered, then move forward by the Home Offset value (in microsteps) and call this position 0.

Note that the home offset command also changes the range. For example, if the initial home offset is 0 and the range is 500,000, and the user changes the home offset to 70,000, then the range is automatically adjusted to be 430,000. However, changing the range does not affect the home offset.

This setting is stored in non-volatile memory and will persist after power-down or reset.

[edit] Set Alias Number - Cmd 48

Instruction Name	Set Alias Number
Firmware Version	5.00 and up
Command Number	48
Command Type	Setting
Command Data	Alias Number
Reply Data	Alias Number
Persistence	Non-Volatile
Summary	Sets an alternate device number for a device.

This setting specifies an alternate device number for a device (in addition to its actual device number). By setting several devices to the same alias number, you can control a group of devices with a single instruction. When you send an instruction to an alias number, all devices with that alias number will execute the instruction and reply using their actual device numbers. To remove an alias, simply set the device's alias number to zero. Valid alias numbers are between 0 and 254. To avoid confusion, it is best to choose an alias greater than the number of devices connected.

This setting is stored in non-volatile memory and will persist after power-down or reset.

[edit] Set Lock State - Cmd 49

Instruction Name	Set Lock State
Firmware Version	5.07 and up
Command Number	49
Command Type	Setting
Command Data	Lock State
Reply Data	Lock State
Persistence	Non-Volatile
Summary	Locks or unlocks all non-volatile settings.

Sometimes it is desirable to lock all non-volatile settings to prevent them from being changed inadvertently. After changing all settings as desired, settings can be locked by setting the Lock State to 1. Subsequent attempts to change any non-volatile setting (e.g., Set Target Speed, command 42) will result in an Error Response with an error code of 3600 (settings locked).

How the Restore Settings instruction behaves when the settings are locked depends on the firmware version. In version 5.07 issuing a Restore Settings instruction while the settings are locked will result in an Error Response with an error code of 3600 (settings locked). This behavior was found to confuse many customers so in version 5.08 and up, the behavior was changed such that regardless of the current lock state, issuing a Restore Settings instruction will always return setting values to factory default values and leave settings in an unlocked state.

Settings can also be unlocked by setting the Lock State to 0.

[edit] Return Device Id - Cmd 50

Instruction Name	Return Device Id
Firmware Version	5.00 and up
Command Number	50
Command Type	Read-Only Setting
Command Data	Ignored
Reply Data	Device Id
Persistence	n/a
Summary	Returns the id number for the type of device connected.

See the T-Series/Device_Ids wiki page for a table of device Ids for all Zaber products.

[edit] Return Firmware Version - Cmd 51

Instruction Name	Return Firmware Version
Firmware Version	5.00 and up
Command Number	51
Command Type	Read-Only Setting
Command Data	Ignored
Reply Data	Version
Persistence	n/a
Summary	Returns the firmware version installed on the device.

A decimal is assumed before the last two digits. For example, 502 indicates firmware version 5.02.

[edit] Return Power Supply Voltage - Cmd 52

Instruction Name	Return Power Supply Voltage
Firmware Version	5.00 and up
Command Number	52
Command Type	Read-Only Setting
Command Data	Ignored
Reply Data	Voltage
Persistence	n/a
Summary	Returns the voltage level of the device's power supply.

A decimal is assumed before the last digit. For example, a value of 127 indicates 12.7 V. Note that the internal voltage measurement is not very accurate. Don't be alarmed if the indicated voltage is slightly different from your measurements.

[edit] Return Setting - Cmd 53

Instruction Name	Return Setting
Firmware Version	5.00 and up
Command Number	53
Command Type	Command
Command Data	Setting Number
Reply Data	Setting Value
Persistence	n/a
Summary	Returns the current value of the setting specified in the Command Data.

Valid setting numbers are the command numbers of any "Set..." instruction. The device will reply using the command number of the specified setting (as if a command to change the setting had just been issued) but the setting will not be changed.

For example, command #48 is the "Set Alias" instruction. Therefore if you wish to return the current value of the alias number, simply send the Return Setting instruction with data of 48. The device will reply with command #48 and data equal to the setting value.

[edit] Return Status - Cmd 54

Instruction Name	Return Status
Firmware Version	5.00 and up
Command Number	54
Command Type	Read-Only Setting
Command Data	Ignored
Reply Data	Status
Persistence	n/a
Summary	Returns the current status of the device.

Status codes are as follows:

• 0 - idle, not currently executing any instructions
• 1 - executing a home instruction
• 10 - executing a manual move (i.e. the manual control knob is turned)
• 20 - executing a move absolute instruction
• 21 - executing a move relative instruction
• 22 - executing a move at constant speed instruction
• 23 - executing a stop instruction (i.e. decelerating)

[edit] Echo Data - Cmd 55

Instruction Name	Echo Data
Firmware Version	5.04 and up
Command Number	55
Command Type	Command
Command Data	Data
Reply Data	Data
Persistence	n/a
Summary	Echoes back the same Command Data that was sent.

This command is useful for testing communication, similar to a network "ping".

[edit] Reply-Only Reference

In general, a T-series device will reply to an instruction using the same command number as the instruction itself. However, there are occasions (such as when the user turns the potentiometer) when the device may transmit data without first receiving a request from the controlling computer. This type of reply may be considered to be a triggered reply as opposed to a requested reply. In this case the device uses a “reply-only” command number to distinguish the reply from those requested by the controlling computer. The meanings of these replies and their corresponding data are given below.

[edit] Constant Speed Tracking - Cmd 8

Instruction Name	Constant Speed Tracking
Firmware Version	5.00 and up
Command Number	8
Command Type	Reply
Command Data	n/a
Reply Data	Tracking Position
Persistence	n/a
Summary	Indicates to the user that the device has been set to a position tracking mode and given a move instruction.

The device has been set to position tracking mode (see Set Mode instruction) and given a move instruction. In this mode, the device sends this reply every 0.25 seconds updating the current absolute position (in microsteps) during any move.

[edit] Limit Active - Cmd 9

Instruction Name	Limit Active
Firmware Version	5.00 and up
Command Number	9
Command Type	Reply
Command Data	n/a
Reply Data	Final Position
Persistence	n/a
Summary	Indicates to the user that the device has reached one of the limits of travel.

This response from a device indicates that it reached one of the limits of travel (either the minimum position or maximum position). For example, if a device is sent a “move at constant speed” instruction, and it reaches the maximum range of travel then the device will reply with this command number and the maximum position reached as data.

[edit] Manual Move Tracking - Cmd 10

Instruction Name	Manual Move Tracking
Firmware Version	5.00 and up
Command Number	10
Command Type	Reply
Command Data	n/a
Reply Data	Tracking position
Persistence	n/a
Summary	A reply that is sent when the manual control knob is turned.

The device has been moved manually (the knob is turned). If enabled with the Set Mode instruction, the device sends this reply at regular intervals updating the current position during manual moves.

[edit] Error - Cmd 255

Instruction Name	Error
Firmware Version	5.00 and up
Command Number	255
Command Type	Reply
Command Data	n/a
Reply Data	Error Code
Persistence	n/a
Summary	Indicates to the user that an error has occurred.

This reply indicates that an error has occurred. The error code returned in the data indicates the type of error. The device may send an error code as a reply to an invalid instruction, or it may autonomously send an error code as a triggered reply (i.e. not in response to an instruction). The error code is typically the command number of the instruction that caused the error, but not always.

[edit] Error Codes for Motion Products