Precision Turntable

RS-232 Programming Manual
Precision Turntable
RS-232 Programming Manual
LT360 Precision Turntable
1
RS-232 Programming Manual
LT360 Precision Turntable
RS-232 Programming Manual
© 2006 LINEARX SYSTEMS INC.
All Rights Reserved.
Tel: (503) 612-9565
Fax: (503) 612-9344
Printed in the United States of America.
March 30, 2006.
This document was produced on a Pentium-4 / 2GHz PC with Win2K using Adobe PageMaker 7.0, Adobe
Illustrator 10.0, Adobe PhotoShop 7.0, MathType 4.0 for mathematics typography, and SnagIt 5.2 for screen
captures. Final masters were produced using an Xerox Docutech image setter. Help files were composed and
compiled using Windows Help Designer 3.1.
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LT360 Precision Turntable
RS-232 Programming Manual
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If this software is acquired by or on behalf of the U.S. Federal government or its agencies, this provision applies. Use, duplication, or disclosure of this software
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LinearX Systems Inc.
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Tualatin, OR 97062-8586 USA
TEL:(503) 612-9565
FAX:(503) 612-9344
Copyright 2006, LinearX Systems Inc. All rights reserved.
LT360 Precision Turntable
WEB: www.linearx.com
All other Trademarks are the property of their respective owners.
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RS-232 Programming Manual
Technical Support
LinearX provides detailed printed manuals and on-line help within the program as the primary
source for user information and assistance regarding the use of this product. If these sources do
not contain the answers to your questions, contact LinearX via any of the following methods:
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Technical support is free and unlimited at this time, however we reserve the right to charge for
this service in the future as conditions, overhead, and support personnel requirements dictate.
When contacting us regarding a technical support issue, PLEASE follow these steps to aid us in
understanding and solving your problem:
(1) If your question involves specific details or parameters unique to your project and problem, please include a copy of
your design files with the necessary data so that we can reproduce your problem. This is only possible if you are
communicating via an electronic means such as Email or uploading files directly to our web site.
(2) If the issue regards error messages from the program, please include an exact description of the error message
and/or address information that the program reports.
(3) If there are specific steps involved to reproduce the issue, please note these exact steps required so that we can
reproduce the problem.
Note: Technical support does not include programming assistance. It is assumed that the reader has sufficient
experience and knowledge to incorporate the RS-232 interface into their own application.
Technical support hours are: Monday-Friday 9:00AM to 5:00PM Pacific Standard Time.
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LT360 Precision Turntable
RS-232 Programming Manual
Contents
Chapter 1: Overview
1.1
1.2
1.3
1.4
1.5
1.6
1.7
Overview of RS-232 ................................................................ 7
Electrical Connection & Wiring ................................................. 8
Communication Parameters ...................................................... 9
Termination Characters ........................................................... 10
Command Buffer & Timing Issues .......................................... 11
Example RS-232 Commands .................................................. 12
Error Messages ...................................................................... 13
Chapter 2: Command Reference
2.1 Goto CCW ..........................................................................
2.2 Goto CW ...........................................................................
2.3 Step CCW .....................................................................
2.4 Step CW ....................................................................
2.5 Set Smart Torque ....................................................
2.6 Set Baud Rate .........................................................
2.7 Set Origin ....................................................................
2.8 Set Pulse Direction ........................................................
2.9 Set Pulse Edge ...........................................................
2.10 Set Step Size ..........................................................
2.11 Set Velocity ...........................................................
2.12 Set Torque ............................................................
2.13 Set Acceleration Function ..........................................
2.14 Set Name ...............................................................
2.15 Set Pulse Input ......................................................
2.16 Set Analog Input ......................................................
2.17 Set Display Polarity ................................................
2.18 Set Input Polarity ...................................................
2.19 Set Output Polarity ................................................
2.20 Set Move Abort ....................................................
2.21 Set Motor Home Check .........................................
2.22 Set Output Mode .....................................................
2.23 Get Name ...............................................................
2.24 Get Title ...............................................................
2.25 Get Firmware Version .............................................
2.26 Get Firmware Date ..................................................
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19
19
20
21
22
23
24
25
26
27
28
29
30
31
33
34
35
36
37
38
39
40
41
43
44
45
46
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RS-232 Programming Manual
Contents
2.27
2.28
2.29
2.30
2.31
2.32
2.33
2.34
2.35
2.36
2.37
2.38
2.39
2.40
2.41
2.42
2.43
2.44
2.45
2.46
2.47
2.48
6
Get
Get
Get
Get
Get
Get
Get
Get
Get
Get
Get
Get
Get
Get
Get
Get
Get
Get
Get
Get
Get
Get
Production Date ..................................................
Calibration Date ..................................................
Calibration Due .....................................................
Serial Number ......................................................
Baud Rate ............................................................
Position ............................................................
Pulse Direction ...................................................
Pulse Edge ..........................................................
Step Size ...........................................................
Velocity ............................................................
Torque ............................................................
Acceleration Function ........................................
Moving ............................................................
Pulse Input .........................................................
Analog Input ....................................................
Smart Torque .......................................................
Display Polarity ....................................................
Input Polarity ......................................................
Output Polarity ...................................................
Motor Home Check ..............................................
Revision Code ....................................................
Output Mode ......................................................
47
48
49
50
51
52
53
54
55
56
57
58
60
61
62
63
64
65
66
67
68
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LT360 Precision Turntable
RS-232 Programming Manual
1.1 Overview of RS-232
The RS-232 industry standard serial interface provides a universal means to
control the LT360 by any program in any operating system environment.
RS-232 still has many advantages over the newer bus formats such as USB.
The length of a cable run for RS-232 is not restricted, and the commands
can be sent to the LT360 from any program, device, or operating system.
Note: If you are using the Windows OS, then the Win32 LT360LIB.dll provides
an easier means for custom programming support. Please refer to the DLL
Programming Manual for more details.
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RS-232 Programming Manual
1.2 Electrical Connection & Wiring
The LT360 provides a female DB-9 connector on the front panel for
connection to the RS-232 serial host. If your host/computer has a DB25, you will need to utilize a DB-25F to DB-9M adapter or cable.
The LT360 is configured as a true DCE (Data Communications Equipment) device and therefore only requires a straight-through cable
connection. A null modem adapter/cable is not required and should
not be used.
Within the DB-9, only 2 signals are used besides Ground: RX and TX.
None of the handshaking control lines are used. The LT360 serial
interface does not require either hardware or software handshaking.
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RS-232 Programming Manual
1.3 Communication Parameters
The LT360 is configured with the following serial parameters:
■ Baud Rate
■ Data Bits
■ Parity
■ Stop Bits
■ Handshaking
9600 (factory default)
8
None
1
None
The user can change the baud rate to higher values as desired. The maximum baud rate is 57600. The following are some typical baud rate values:
9600
14400
19200
28800
38400
57600
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RS-232 Programming Manual
1.4 Termination Characters
Each and every command string that is sent to the LT360 must be
terminated with a special character. Either with a Carriage Return
Chr(13) or Null Chr(0). The LT360 accepts either character for string
termination.
Examples are:
■ Goto CCW -45.0 [13]
■ Set DisplayPolarity UNIPOLAR[0]
The termination character tells the LT360 that the command string is
complete and that it can now be processed. After the command string
is processed, it is cleared and the command buffer is empty.
The LT360 employs a time-out of 10 seconds after the reception of the
first character. If a termination character is not received within 10
seconds, then an error message is displayed on the front panel and the
command buffer/string is cleared. This prevents corrupt data from
building up in the command buffer.
Therefore, command strings must be sent to the LT360 complete within
10 seconds. This is of little concern when the data is being sent from a
computer program which will send the data at line speed. However, if
you are typing commands manually at a terminal or communication
program, you must type in the command string within 10 seconds along
with the [CR].
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RS-232 Programming Manual
1.5 Command Buffer & Timing Issues
The LT360 contains a single command buffer. Each command must be
processed by the LT360 before another command is sent by the host.
Otherwise a command overflow would occur resulting in a corrupted
command.
For this reason the LT360 always returns a string from all commands. The
host must wait for this response string before sending another command.
This command/response sequence automatically ensures that every command is processed before another is sent.
There are two classes of commands: Set commands and Get commands.
The Set class of commands also includes the Step and Goto commands and
these only send information to the LT360. However, the LT360 returns an
'Ok' acknowledgement response string to all Set commands.
The Get commands cause the LT360 to return actual data strings to the host.
All commands are self timing due to the fact that the host must wait for data
or 'Ok' strings to be returned from the LT360. Generally the host cannot
send another command until it has received the last response from the
previous command, and this means that the LT360 has completed processing the previous command.
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RS-232 Programming Manual
1.6 Example RS-232 Commands
All commands sent to the LT360 can be either upper or lower case.
Numeric parameters when needed for Set commands are contained in
the string at the end, and then followed by a termination character.
There must be a [space] delimiter between the Set or Get word and the
command name, and again between the parameter if used. The final
termination character must follow to inform the LT360 that the command string is now complete and can be processed.
The following are some LT360 command examples, where
[CR]=Chr(13) and [NULL]=Chr(0) are equivalent. All strings returned by
the LT360 have a [NULL]=Chr(0) as the last character.
■ Goto CCW -45.0[CR]
(LT360 returns: Ok[0])
Move the platter counter clockwise to the -45.0 (315.0) degree position.
■ Step CCW[CR]
(LT360 returns: Ok[0])
Step the platter counter clockwise by the current step size.
■ Set InputPolarity BIPOLAR[NULL]
(LT360 returns: Ok[0])
Set the Analog Input for bipolar voltage input mode: 0..±1.800
■ Get StepSize[CR]
(LT360 returns: 5.00[0])
Get the current step size, returned as an ASCIIZ string such as 5.00 in
degrees.
■ Get PulseInput[NULL]
(LT360 returns: OFF[0])
Get the current status for the Pulse Input, returned as an ASCIIZ string
either OFF or ON.
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1.7 Error Messages
The LT360 can display a variety of error codes on the front panel
display. The error message will be displayed over a 4 second interval
with a format such as Err0 or Er13.
The following list describes some of the error codes which can appear:
//------------------------------------------------// Show Error Display Codes
//------------------------------------------------//
0
Motor Home Position Error
//
1
RS232-OE Overrun Error
//
2
RS232-PE Parity Error
//
3
RS232-FE Framing Error
//
4
RS232-BI Break Int Error
//
5
RS232 Unknown Command
//
6
RS232 Invalid Parameter
//
7
RS232 Invalid Return
//
8
USB
Unknown Command
//
9
RS232 Command Timeout
//
10
//
11
Display Cntrlr Adr Failure
//
12
Switch Cntrlr Adr Failure
//
13
Torque Cntrlr Adr Failure
//
14
Output Cntrlr Adr Failure
//
15
//
16
//
17
//
18
//
19
//
20
//-------------------------------------------------
Most errors produced by the LT360 will be RS-232 command or
parameter errors, especially if the user is programming via RS-232. The
USB processing routines also rely on the RS-232 command decoders, so
it is very possible to see RS-232 error codes while using the USB
interface.
The basic LT360 serial RS-232 communication parameters are: 9600
baud, 8 data bits, no parity, 1 stop bit, and no flow control.
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RS-232 Programming Manual
Error - 0 : Motor Home Position Error
The stepper motor produces a specific number steps for a given amount
of platter rotation. The LT360 utilizes microstepping for additional
precision control. One particular phase of the motor is designated as
the Home position. For any given platter rotation, the motor should
always end in its Home position. This is checked by the firmware
continuously, if the MotorHomeChk option is enabled. If the motor
position is not in the Home phase at the end of a movement, this error
will be shown.
In normal operation this error should never occur. If it does, the unit
must be powered off, or the MotorHomeChk option disabled, to clear
the error. It is possible for this error to be produced by noise in the
stepper motor controller, or by the load exceeding the torque capability
thereby causing the motor to skip steps.
If this error is shown repeatedly, either there is a noise problem internal
in the LT360 or the torque load is too great for the drive system.
Error - 1 : RS232-OE Overrun Error
This error indicates problems with the serial port communications. It
can be caused by differences in the communication parameters between the computer and the LT360. Make sure that the computer serial
port setup is 9600 baud, 8 data bits, no parity, and 1 stop bit. If the
LT360 baud rate has been changed, then the PC must be set the same.
Error - 2 : RS232-PE Parity Error
This error indicates problems with the serial port communications. It
can be caused by differences in the communication parameters between the computer and the LT360. Since the LT360 does not use
parity, this error is unlikely. Make sure that the computer serial port
setup is 9600 baud, 8 data bits, no parity, and 1 stop bit. If the LT360
baud rate has been changed, then the PC must be set the same.
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RS-232 Programming Manual
Error - 3 : RS232-FE Framing Error
This error indicates problems with the serial port communications. It can be
caused by differences in the communication parameters between the
computer and the LT360, or invalid parameters in the computer UART of
the computer. Make sure that the computer serial port setup is 9600 baud,
8 data bits, no parity, and 1 stop bit. If the LT360 baud rate has been
changed, then the PC must be set the same. You may also need to reboot
the computer to clear and reinitialize the UART in the computer.
Error - 4 : RS232-BI Break Int Error
This error indicates problems with the serial port communications. It can be
caused by differences in the communication parameters between the
computer and the LT360. Make sure that the computer serial port setup is
9600 baud, 8 data bits, no parity, and 1 stop bit. If the LT360 baud rate has
been changed, then the PC must be set the same.
Error - 5 : RS232 Unknown Command
This error indicates that the character string sent to the LT360 did not
contain a valid command. This error will generally occur if you are writing
your own RS-232 program, and there are bugs in your program. Check the
command strings being sent to verify that they contain valid LT360 commands. Case is not important, but spaces in the right or wrong places can
make a difference.
Error - 6 : RS232 Invalid Parameter
This error indicates that the LT360 was expecting a parameter value for this
command, but did not find one in the command string. Some commands
need parameters and some do not. This error will generally occur if you are
writing your own RS-232 program, and there are bugs in your program.
Check the command strings being sent to verify that they contain valid
LT360 commands and parameters. Case is not important, but spaces in the
right or wrong places can make a difference.
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RS-232 Programming Manual
Error - 7 : RS232 Invalid Return
This error indicates that the LT360 was expecting to produce a return
value for a Get command, but the return value was an empty string.
This error will generally occur if you are writing your own RS-232
program, and there are bugs in your program. Check the command
strings being sent to verify that they contain valid LT360 commands
and/or parameters. Case is not important, but spaces in the right or
wrong places can make a difference.
Error - 8 : USB Unknown Command
This error indicates that the LT360 did not understand the command
index sent via USB. This error is very uncommon. It probably indicates
faulty communication over USB, such as a cable being disconnected or
dirty connections. Possibly some other unusual problem.
Error - 9 : RS232 Command Timeout
This error indicates that the LT360 received some characters, but never
received a termination character [Null(0) or CR(13)] before the 10
second timeout expired. When the first character is sent to the LT360, a
timer is started. If a termination character is not received within 10
seconds, then this error is produced and the command buffer is cleared.
Receiving all of the characters for a command string should take very
little time, on the order of micro or milli seconds, so if a termination
charcater does not arrive within 10 seconds, something is wrong. The
LT360 uses this timeout to clear the command buffer every 10 seconds
if characters are received with no termination character. The termination character is mandatory to notify the LT360 that the entire command string has been sent and it can now process it.
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RS-232 Programming Manual
Error - 11: Display Controller Address Failure
This error indicates that the CPU in the LT360 cannot communicate with the
display controller. This error should never occur. If it does, a failure of a
component in the LT360 is indicated.
Error - 12: Switch Controller Address Failure
This error indicates that the CPU in the LT360 cannot communicate with the
switch controller. This error should never occur. If it does, a failure of a
component in the LT360 is indicated.
Error - 13: Torque Controller Address Failure
This error indicates that the CPU in the LT360 cannot communicate with the
stepper motor torque DAC controller. This error should never occur. If it
does, a failure of a component in the LT360 is indicated.
Error - 14: Output Controller Address Failure
This error indicates that the CPU in the LT360 cannot communicate with the
analog output DAC controller. This error should never occur. If it does, a
failure of a component in the LT360 is indicated.
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RS-232 Programming Manual
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2.1 Goto CCW
■ Class
■ RS-232 String
■ Parameter
■ Returns
Set (out)
GoTo CCW ±nnn.n [CR]
Position (degrees)
Ok[0]
Description
This command causes the LT360 to move to the desired location specified
by the parameter value using counter clockwise rotation. If the LT360 is
already at this location, no movement occurs.
The parameter value should have tenths of a degree precision, and may be
either unipolar (0..+360.0) or bipolar (0..±180.0).
The Goto 0 command can also be issued from the front panel of the unit, or
the LR360 remote using the switches on the front panel.
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RS-232 Programming Manual
2.2 Goto CW
■ Class
■ RS-232 String
■ Parameter
■ Returns
Set (out)
GoTo CW ±nnn.n [CR]
Position (degrees)
Ok[0]
Description
This command causes the LT360 to move to the desired location
specified by the parameter value using clockwise rotation. If the LT360
is already at this location, no movement occurs.
The parameter value should have tenths of a degree precision, and may
be either unipolar (0..+360.0) or bipolar (0..±180.0).
The Goto 0 command can also be issued from the front panel of the
unit, or the LR360 remote using the switches on the front panel.
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RS-232 Programming Manual
2.3 Step CCW
■ Class
■ RS-232 String
■ Parameter
■ Returns
Set (out)
Step CCW [CR]
(none)
Ok[0]
Description
This command causes the LT360 to move from its current position by the
current step size using counter clockwise rotation. No parameter is required.
The step command can also be issued from the front panel of the unit, the
LR360 remote, or by the TTL Pulse input on the front panel.
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RS-232 Programming Manual
2.4 Step CW
■ Class
■ RS-232 String
■ Parameter
■ Returns
Set (out)
Step CW [CR]
(none)
Ok[0]
Description
This command causes the LT360 to move from its current position by
the current step size using clockwise rotation. No parameter is required.
The step command can also be issued from the front panel of the unit,
the LR360 remote, or by the TTL Pulse input on the front panel.
The parameter value should have tenths of a degree precision, and may
be either unipolar (0..360.0) or bipolar (0..±180.0).
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RS-232 Programming Manual
2.5 Set Smart Torque
■ Class
■ RS-232 String
■ Parameter
■ Returns
Set (out)
Set SmartTorque xxx [CR]
'OFF' or 'ON'
Ok[0]
Description
This command controls the behavior of the stepper motor. When
SmartTorque is set ON, the motor is powered down to half the driving
power 2 seconds after each movement stops. Motor power is returned to
full (as controlled by the Maximum Torque setting) when the motor starts
again.
This feature takes advantage of the fact that the worm gear drive system
employed by the LT360 is irreversible. Meaning, the platter is self-locking at
its current position. The load cannot rotate the platter itself. Therefore, it is
not necessary to maintain full power on the motor merely to hold its current
position when the platter is not in movement.
The use of SmartTorque greatly reduces the thermal heating in the motor
and driver circuitry, and produces a very efficient drive system. Under most
conditions and use, this feature should always be kept ON.
If a particular application demands that the motor power be kept constant at
all times, even when stationary (SmartTorque=OFF), then the maximum
torque should be to 70% or less to prevent excessive heating. It is difficult
to envision what kinds of applications would require this behavior, but the
option is available if needed.
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RS-232 Programming Manual
2.6 Set Baud Rate
■ Class
■ RS-232 String
■ Parameter
■ Returns
Set (out)
Set BaudRate nnnnn [CR]
Baud rate, eg. '9600'
Ok[0]
Description
This command sets the baud rate for RS-232 communications. Once
the new baud rate is set, all further RS-232 communication with an
LT360 must be at the new baud rate.
Legal baud rate values are:
9600
14400
19200
28800
38400
57600
Note: While increasing the baud rate will provide faster communication,
it will not necessarily produce a direct ratio effect on the speed of
communication and commands with the LT360. The LT360 has a
response time for commands which is dependent on many factors
internally. The CPU must perform many other tasks so there can be a
latency of several mSec before the commands are processed regardless of
the baudrate.
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2.7 Set Origin
■ Class
■ RS-232 String
■ Parameter
■ Returns
Set (out)
Set Origin [CR]
(none)
Ok[0]
Description
This command resets the rotational origin to that of the current platter
position. No parameters are required, and the platter does not rotate. All
further goto commands will be referenced to this new origin (0.0).
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RS-232 Programming Manual
2.8 Set Pulse Direction
■ Class
■ RS-232 String
■ Parameter
■ Returns
Set (out)
Set PulseDir xxx [CR]
'CCW' or 'CW'
Ok[0]
Description
This command controls the behavior to a TTL step pulse at the Pulse
input BNC connector. The parameter string can be either CCW or CW,
meaning counter clockwise or clockwise.
When a pulse arrives at the Pulse BNC input, the platter will rotate
either CCW or CW as defined by this setting. The size of the step is
controlled by the Set StepSize command.
Note: The TTL pulse should be a minimum of 10uS, or longer. The
triggering edge can be controlled by the Set PulseEdge command.
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2.9 Set Pulse Edge
■ Class
■ RS-232 String
■ Parameter
■ Returns
Set (out)
Set PulseEdge xxxx [CR]
'RISE' or 'FALL'
Ok[0]
Description
This command controls the behavior to a TTL step pulse at the Pulse input
BNC connector. The parameter string can be either RISE or FALL, meaning
triggering occurs on the rising or falling edge of the pulse.
When a pulse arrives at the Pulse BNC input, the platter will rotate either at
the rising or falling edge as defined by this setting. The size of the step is
controlled by the Set StepSize command.
Note: The TTL pulse should be a minimum of 10uS, or longer. The direction
can be controlled by the Set PulseDir command.
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2.10 Set Step Size
■ Class
■ RS-232 String
■ Parameter
■ Returns
Set (out)
Set StepSize nn.n [CR]
Step Size (degrees)
Ok[0]
Description
This command sets the angular step size by which the platter will rotate
to either a step command or TTL pulse. The parameter string must
contain a numeric value such as '15.0' with tenth of a degree precision.
The minimum step size is 0.1 degrees. Step size is always positive.
Direction is controlled by the CCW/CW commands listed else where.
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2.11 Set Velocity
■ Class
■ RS-232 String
■ Parameter
■ Returns
Set (out)
Set Velocity n.nn [CR]
Velocity (RPM)
Ok[0]
Description
This command sets the angular velocity by which the platter will rotate. The
value is set in RPM (revolutions per minute). The allowable range for the
parameter is 0.01 to 3.00 RPM.
The parameter string must contain a numeric value such as '1.00' with
hundreths precision.
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2.12 Set Torque
■ Class
■ RS-232 String
■ Parameter
■ Returns
Set (out)
Set Torque nnn.n [CR]
Torque (%)
Ok[0]
Description
This command sets the stepper motor torque for the platter rotation.
The value is set in percent of maximum torque. The allowable range for
the parameter is 10.0 to 100.0 %.
The parameter string must contain a numeric value such as '100.0' with
tenths of a degree precision.
For most typical applications your will want the torque set to 100%. If
you intend to have the platter in constant motion, than you may wish to
set the torque to a lower value such as 70%. This will reduce heating in
the motor and drive circuitry.
The SmartTorque feature of the LT360 automatically reduces the motor
torque to 1/2 its normal rotational power when it is not moving. Thus
providing the advantages of maximum torque when in motion and
reduced power consumption when stationary.
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2.13 Set Acceleration Function
■ Class
■ RS-232 String
■ Parameter
■ Returns
Set (out)
Set AccelFunc n [CR]
Function Number 0..4
Ok[0]
Description
This command sets the acceleration function which the LT360 will use
during step or goto commands. The acceleration profile is an important
feature of the LT360 which enables heavy loads to be moved with minimum
disturbance.
The parameter string must contain a numeric value such as '1' with allowable
values from 0..4. There are five acceleration functions numbered 0,1,2,3,4.
The names of these profiles are:
0 - Impulse
1 - Flat
2 - Ramp
3 - Sin2
4 - Sin3
For most typical applications acceleration function 1 - FLAT will provide
excellent performance. Because the LT360 controls the acceleration and
deceleration so precisely, very heavy loads can be rotated with ease.
The 0 - IMPULSE function provides the fastest rise time from zero to constant velocity. However it also greatly reduces the maximum load which the
LT360 can rotate, due to its higher acceleration. The acceleration of this
function is about 10X that of the others.
The graphs on the following page show the velocity and acceleration profile
curves for the five different LT360 functions.
LT360 Precision Turntable
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RS-232 Programming Manual
LT360 VELOCITY PROFILES
3-SIN2
0-IMPULSE
2-
R
A
M
P
1-
FL
A
T
4-SIN3
ACCELERATION
CONSTANT VELOCITY
DECELERATION
LT360 ACCELERATION PROFILES
2-
R
A
M
P
0-IMPULSE
1-FLAT
3-SIN2
4-SIN3
NOTE: HEIGHT OF IMPULSE IS 10X FLAT
ACCELERATION
32
CONSTANT VELOCITY
DECELERATION
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RS-232 Programming Manual
2.14 Set Name
■ Class
■ RS-232 String
■ Parameter
■ Returns
Set (out)
Set Name xxxxxxxxxx [CR]
Name
Ok[0]
Description
This command sets the Name for the LT360 unit. This is an arbitrary user
name which can be assigned to the unit. This can be useful for applications
which utilize multiple units to distinguish between the units, for example
Horz, Vert, etc. This name is stored in the LT360 and is non volatile.
The Name parameter string has a maximum length of 21 characters.
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2.15 Set Pulse Input
■ Class
■ RS-232 String
■ Parameter
■ Returns
Set (out)
Set PulseInput xxx [CR]
'OFF' or 'ON'
Ok[0]
Description
This command enables the TTL Pulse Input feature. When PulseInput is
set ON, the LT360 will respond to TTL pulses at the BNC connector.
When it is set OFF, it will ignore any pulses.
Each pulse will trigger a step. The width of the pulse should be at least
10uSec, and the triggering can be set on the rising or falling edge. Any
pulses which occur while the LT360 is moving will be ignored.
If you are not using the TTL pulse input, it is probably best to keep this
feature OFF to prevent false triggering due to any noise pickup at the
open connector.
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2.16 Set Analog Input
■ Class
■ RS-232 String
■ Parameter
■ Returns
Set (out)
Set AnalogInput xxx [CR]
'OFF' or 'ON'
Ok[0]
Description
This command enables the Analog Input feature. When AnalogInput is set
ON, the LT360 will respond to the DC voltage at the analog input BNC
connector. When it is set OFF, it will ignore that input.
The LT360 has a scale factor of 10mV/deg for the analog input. The range
can be either unipolar (0 ... +3.600V) or bipolar (0 ... ±1.800V). The input
impedance of the analog input is 1M Ohm. Although the input is an
unbalanced BNC connector, the actually circuitry is differential. This helps
to reject ground noise.
The input source must be very stable and of low noise. The LT360 has a
resolution of 0.1 degrees and therefore responds to changes of 1mV at the
analog input. When this input is enabled, the LT360 will sample the input
and move to the location as indicated by the voltage. After that move is
completed, it then samples the analog input again and moves to the new
position. Monitoring of the analog input is real time.
If you are not using the analog input, this input must be set OFF. Otherwise
the LT360 will be controlled by any noise received at the input.
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2.17 Set Display Polarity
■ Class
■ RS-232 String
■ Parameter
■ Returns
Set (out)
Set DisplayPolarity xxxxxxxx [CR]
'UNIPOLAR' or 'BIPOLAR'
Ok[0]
Description
This command changes how the LT360 represents the degree position
on the front display of the chassis, and in the Win32 software. When
DisplayPolarity is set to UNIPOLAR, the LT360 will display the position
in the range of 0 to 360 degrees. All position values are positive. When
it is set to BIPOLAR, the range will be 0 to ±180 degrees. Both positive
and negative values will be shown.
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2.18 Set Input Polarity
■ Class
■ RS-232 String
■ Parameter
■ Returns
Set (out)
Set InputPolarity xxxxxxxx [CR]
'UNIPOLAR' or 'BIPOLAR'
Ok[0]
Description
This command changes how the LT360 interprets the DC voltage received
at the Analog Input connector. When InputPolarity is set to UNIPOLAR, the
LT360 will accept voltages in the range of 0.000 to +3.600 volts. All position values are positive. When it is set to BIPOLAR, the range will be 0.000
to ±1.800 volts. Both positive and negative values are used.
Voltages higher than the allowable range for the selected mode are invalid.
The LT360 has a scale factor of 10mV/deg for the analog input. The range
can be either unipolar (0 ... +3.600V) or bipolar (0 ... ±1.800V). The input
impedance of the analog input is 1M Ohm. Although the input is an
unbalanced BNC connector, the actually circuitry is differential. This helps
to reject ground noise.
The input source must be very stable and of low noise. The LT360 has a
resolution of 0.1 degrees and therefore responds to changes of 1mV at the
analog input. When this input is enabled, the LT360 will sample the input
and move to the location as indicated by the voltage. After that move is
completed, it then samples the analog input again and moves to the new
position. Monitoring of the analog input is real time.
If you are not using the analog input, this input must be set OFF. Otherwise
the LT360 will be controlled by any noise received at the input.
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2.19 Set Output Polarity
■ Class
■ RS-232 String
■ Parameter
■ Returns
Set (out)
Set OutputPolarity xxxxxxxx [CR]
'UNIPOLAR' or 'BIPOLAR'
Ok[0]
Description
This command changes how the LT360 generates the DC voltage
output at the Analog Output connector. When OutputPolarity is set to
UNIPOLAR, the LT360 will produce voltages in the range of 0.000 to
+3.600 volts. All position values are positive. When it is set to BIPOLAR, the range will be 0.000 to ±1.800 volts. Both positive and negative values are produced.
The LT360 has a scale factor of 10mV/deg for the analog output. The
range can be either unipolar (0 ... +3.600V) or bipolar (0 ... ±1.800V).
The output impedance of the analog output is <200 Ohms. Although
the output is an unbalanced BNC connector, it is highly recommended
that the input on the other device be differential to reject ground noise.
Since the smallest resolution of the LT360 is 0.1 degree, the equivalent
resolution in the output is 1mV. The input impedance of the other
device should be at least 100K Ohm to prevent loading errors.
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2.20 Set Move Abort
■ Class
■ RS-232 String
■ Parameter
■ Returns
Set (out)
Set MoveAbort [CR]
(none)
Ok[0]
Description
This command can be used to terminate the rotation in progress. The LT360
will stop rotating as quickly as possible at any current location. This command can be used as an emergency stop feature if needed.
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RS-232 Programming Manual
2.21 Set Motor Home Check
■ Class
■ RS-232 String
■ Parameter
■ Returns
Set (out)
Set MotorHomeChk xxx [CR]
'OFF' or 'ON'
Ok[0]
Description
This command controls checking of the stepper motor synchronization .
When MotorHomeChk is set ON, the firmware checks that the motor
returns to its home position after each movement. If disabled, no
checking is performed. If checking is enabled and the motor does not
end its operation in the home position, an error message is shown on
the front panel display.
The stepper motor produces a specific number steps for a given amount
of platter rotation. The LT360 utilizes microstepping for additional
precision control. One particular phase of the motor is designated as
the Home position. For any given platter rotation, the motor should
always end in its Home position.
In normal operation this error should never occur. If it does, the unit
must be powered off to clear the error, or this feature disabled. It is
possible for this error to be produced by noise in the stepper motor
controller, or by the load exceeding the torque capability thereby
causing the motor to skip steps.
If this error is shown repeatedly, either there is a problem internal in the
LT360 or the torque load is too great for the drive system.
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2.22 Set Output Mode
■ Class
■ RS-232 String
■ Parameter
■ Returns
Set (out)
Set OutputMode xxxxx [CR]
CONT or START or STOP
Ok[0]
Description
This command selects the operating mode for the Analog Output. The
parameter string value is either CONT or START or STOP.
When CONT is the mode, the Analog Output will continuously follow the
platter position as it is moving. This is a real time output mode where the
analog output voltage always represents the current platter position.
When START is the mode, the Analog Output will only produce a single step
change output voltage representing the final destination position at the start
of the movement. For example, if the current position is 0.0 degrees and
the destination is 100.0 degrees, the Analog Output voltage will change
from 0.000V to 1.000V at the start of the movement.
When STOP is the mode, the Analog Output will only produce a single step
change output voltage representing the final destination position after the
movement stops. For example, if the current position is 0.0 degrees and
the destination is 100.0 degrees, the Analog Output voltage will remain at
0.000V during the movement and then change to 1.000V when the movement stops. The final output voltage changes 2 seconds after the platter
movemet stops.
If the movement is aborted before it reaches the destination, the output
voltage will be updated to the correct final value in all modes.
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RS-232 Programming Manual
LT360 ANALOG OUTPUT MODES
OUTPUT VOLTAGE
START
MODE
CONT
MODE
STOP
MODE
PLATTER MOVEMENT
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2.23 Get Name
■ Class
■ RS-232 String
■ Returns
Get (in)
Get Name [CR]
NameString[0]
Description
This command returns the Name for the LT360 unit. This is an arbitrary
user name which can be assigned to the unit. This can be useful for
applications which utilize multiple units to distinguish between the units,
for example Horz, Vert, etc. This name is stored in the LT360 and is
non volatile.
The Name parameter string has a maximum length of 21 characters.
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RS-232 Programming Manual
2.24 Get Title
■ Class
■ RS-232 String
■ Returns
Get (in)
Get Title [CR]
LT360 Precision Turntable[0]
Description
This command returns the Title of the LT360 unit, which always is LT360
Precision Turntable. This command can be useful if you are writing your
own RS-232 program to control the LT360. This command can be used as
a test to verify that you are communicating with an LT360 unit.
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2.25 Get Firmware Version
■ Class
■ RS-232 String
■ Returns
Get (in)
Get FirmwareVersion [CR]
n.nn[0]
Description
This command returns the version code of the firmware within the LT360.
For example: 1.50 The numeric value is returned as a string.
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RS-232 Programming Manual
2.26 Get Firmware Date
■ Class
■ RS-232 String
■ Returns
Get (in)
Get FirmwareDate [CR]
mmm-dd-yyyy[0]
Description
This command returns the version date of the firmware within the LT360.
For example: JAN-01-2006 The date value is returned as a string.
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2.27 Get Production Date
■ Class
■ RS-232 String
■ Returns
Get (in)
Get ProductionDate [CR]
mmm-dd-yyyy[0]
Description
This command returns the date when the LT360 was manufactured. For
example: JAN-01-2006 The date value is returned as a string.
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RS-232 Programming Manual
2.28 Get Calibration Date
■ Class
■ RS-232 String
■ Returns
Get (in)
Get CalibrationDate [CR]
mmm-dd-yyyy[0]
Description
This command returns the date when the LT360 was last calibrated. For
example: JAN-01-2006 The date value is returned as a string.
Calibration is performed using the Win32 application software. Calibration
is performed originally at the factory, and in most cases will be permanent
and not be required again. It is possible for a customer to performed the
calibration, but only if the proper equipment is available. The computer
must have a GPIB bus, and two 6-1/2 digit DMMs are required themselves
with accurate recent calibration. See the LT360 Manual for further details.
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2.29 Get Calibration Due
■ Class
■ RS-232 String
■ Returns
Get (in)
Get CalibrationDue [CR]
mmm-dd-yyyy[0]
Description
This command returns the date when the LT360 should be re-calibrated.
For example: JAN-01-2007 The date value is returned as a string.
Calibration is performed using the Win32 application software. Calibration is performed originally at the factory, and in most cases will be
permanent and not be required again. However if your application
requires NIST compliance, this is the date when the LT360 should be
rechecked. It is possible for a customer or other lab to performed the
calibration, but only if the proper equipment is available. The computer
must have a GPIB bus, and two 6-1/2 digit DMMs are required themselves with accurate recent calibration. See the LT360 Manual for
further details.
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RS-232 Programming Manual
2.30 Get Serial Number
■ Class
■ RS-232 String
■ Returns
Get (in)
Get SerialNumber [CR]
nnnnnn[0]
Description
This command returns the serial number of the LT360 unit. The number is
returned as a string value of 6 digits.
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2.31 Get Baud Rate
■ Class
■ RS-232 String
■ Returns
Get (in)
Get BaudRate [CR]
nnnnn[0]
Description
This command returns the current baud rate the LT360 is using. The
number is returned as a string value of 4-6 digits.
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RS-232 Programming Manual
2.32 Get Position
■ Class
■ RS-232 String
■ Returns
Get (in)
Get Position [CR]
±nnn.n[0]
Description
This command returns the current position of the LT360 in degrees. The
value is returned as a string with tenths of degree precision. The value may
be 0 to +360.0 or 0 to ±180.0 depending on the settings for the display
polarity.
This command is very useful when you want to know the current position of
the LT360, or if the LT360 has completed a movement. It can be used in a
polling loop to see when the LT360 step or goto command has finished.
Another alternative method would be to call the Get Moving command until
the NO value is returned.
When using either method in a polling loop, the frequency of calls should be
reasonable. Typically, testing for movement completion once every second
is more than adequate.
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2.33 Get Pulse Direction
■ Class
■ RS-232 String
■ Returns
Get (in)
Get PulseDir [CR]
CCW[0] or CW[0]
Description
This command returns the setting for the Pulse Direction. The value is
returned as either CCW (counter clockwise) or CW (clockwise). This
parameter controls the behavior to a TTL step pulse at the Pulse input
BNC connector.
When a pulse arrives at the Pulse BNC input, the platter will rotate
either CCW or CW as defined by this setting. The size of the step is
controlled by the Set StepSize command.
Note: The TTL pulse should be a minimum of 10uS, or longer. The
triggering edge can be controlled by the Set PulseEdge command.
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2.34 Get Pulse Edge
■ Class
■ RS-232 String
■ Returns
Get (in)
Get PulseEdge [CR]
RISE[0] or FALL[0]
Description
This command returns the setting for the Pulse Edge triggering. The
value is returned as either RISE (rising edge) or FALL (falling edge). This
parameter controls the behavior to a TTL step pulse at the Pulse input
BNC connector.
When a pulse arrives at the Pulse BNC input, the platter will rotate
either at the rising or falling edge as defined by this setting. The size of
the step is controlled by the Set StepSize command.
Note: The TTL pulse should be a minimum of 10uS, or longer. The
direction can be controlled by the Set PulseDir command.
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2.35 Get Step Size
■ Class
■ RS-232 String
■ Returns
Get (in)
Get StepSize [CR]
nnn.n[0]
Description
This command returns the step size value. The value is returned as a
string with tenths of a degree precision, and is always positive. This
value sets the angular step size by which the platter will rotate to either
a step command or TTL pulse.
The minimum step size is 0.1 degrees. Step size is always positive.
Direction is controlled by the CCW/CW commands listed else where.
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2.36 Get Velocity
■ Class
■ RS-232 String
■ Returns
Get (in)
Get Velocity [CR]
n.nn[0]
Description
This command returns the velocity in RPM (revolutions per minute). The
value is returned as a string with hundreths precision, and is always positive.
The allowable range for the parameter is 0.01 to 3.00 RPM.
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2.37 Get Torque
■ Class
■ RS-232 String
■ Returns
Get (in)
Get Torque [CR]
nnn.n[0]
Description
This command returns the torque in percent (%). The value is returned
as a string with tenths precision, and is always positive. The allowable
range for the parameter is 10.0 to 100.0 %.
This value sets the stepper motor torque for the platter rotation. The
value is set in percent of maximum torque. For most typical applications your will want the torque set to 100%. If you intend to have the
platter in constant motion, than you may wish to set the torque to a
lower value such as 70%. This will reduce heating in the motor and
drive circuitry.
The SmartTorque feature of the LT360 automatically reduces the motor
torque to 1/2 its normal rotational power when it is not moving. Thus
providing the advantages of maximum torque when in motion and
reduced power consumption when stationary.
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2.38 Get Acceleration Function
■ Class
■ RS-232 String
■ Returns
Get (in)
Get AccelFunc [CR]
n[0]
Description
This command returns the acceleration function number (0 to 4). This value
gives the acceleration function which the LT360 will use during step or goto
commands. The acceleration profile is an important feature of the LT360
which enables heavy loads to be moved with minimum disturbance.
The parameter string contains a numeric value such as '1' with allowable
values from 0..4. There are five acceleration functions numbered 0,1,2,3,4.
The names of these profiles are:
0 - Impulse
1 - Flat
2 - Ramp
3 - Sin2
4 - Sin3
For most typical applications acceleration function 1 - FLAT will provide
excellent performance. Because the LT360 controls the acceleration and
deceleration so precisely, very heavy loads can be rotated with ease.
The 0 - IMPULSE function provides the fastest rise time from zero to constant velocity. However it also greatly reduces the maximum load which the
LT360 can rotate, due to its higher acceleration. The acceleration of this
function is about 10X that of the others.
The graphs on the following page show the velocity and acceleration profile
curves for the five different LT360 functions.
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LT360 VELOCITY PROFILES
3-SIN2
0-IMPULSE
2-
R
A
M
P
1-
FL
A
T
4-SIN3
ACCELERATION
CONSTANT VELOCITY
DECELERATION
LT360 ACCELERATION PROFILES
2-
R
A
M
P
0-IMPULSE
1-FLAT
3-SIN2
4-SIN3
NOTE: HEIGHT OF IMPULSE IS 10X FLAT
ACCELERATION
LT360 Precision Turntable
CONSTANT VELOCITY
DECELERATION
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RS-232 Programming Manual
2.39 Get Moving
■ Class
■ RS-232 String
■ Returns
Get (in)
Get Moving [CR]
CCW[0] or CW[0] or NO[0]
Description
This command returns the rotational status of the LT360. Three possible
string values can be returned:
CCW - rotating counter clockwise
CW
- rotating clockwise
NO
- not rotating
This command is very useful when you want to know if the LT360 has
completed a movement. It can be used in a polling loop to see when the
LT360 step or goto command has finished. Another alternative method
would be to call the Get Position command until the desired location is
returned.
When using either method in a polling loop, the frequency of calls should be
reasonable. Typically, testing for movement completion once every second
is more than adequate.
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2.40 Get Pulse Input
■ Class
■ RS-232 String
■ Returns
Get (in)
Get PulseInput [CR]
OFF[0] or ON[0]
Description
This command returns the status for the Pulse Input BNC function of the
LT360. The returned string value is either OFF or ON.
This parameter enables the TTL Pulse Input feature. When PulseInput is
set ON, the LT360 will respond to TTL pulses at the BNC connector.
When it is set OFF, it will ignore any pulses.
Each pulse will trigger a step. The width of the pulse should be at least
10uSec, and the triggering can be set on the rising or falling edge. Any
pulses which occur while the LT360 is moving will be ignored.
If you are not using the TTL pulse input, it is probably best to keep this
feature OFF to prevent false triggering due to any noise pickup at the
open connector.
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2.41 Get Analog Input
■ Class
■ RS-232 String
■ Returns
Get (in)
Get AnalogInput [CR]
OFF[0] or ON[0]
Description
This command returns the status for the Analog Input BNC function of the
LT360. The returned string value is either OFF or ON.
This parameter enables the Analog Input feature. When AnalogInput is set
ON, the LT360 will respond to the DC voltage at the analog input BNC
connector. When it is set OFF, it will ignore that input.
The LT360 has a scale factor of 10mV/deg for the analog input. The range
can be either unipolar (0 ... +3.600V) or bipolar (0 ... ±1.800V). The input
impedance of the analog input is 1M Ohm. Although the input is an
unbalanced BNC connector, the actually circuitry is differential. This helps
to reject ground noise.
The input source must be very stable and of low noise. The LT360 has a
resolution of 0.1 degrees and therefore responds to changes of 1mV at the
analog input. When this input is enabled, the LT360 will sample the input
and move to the location as indicated by the voltage. After that move is
completed, it then samples the analog input again and moves to the new
position. Monitoring of the analog input is real time.
If you are not using the analog input, this input must be set OFF. Otherwise
the LT360 will be controlled by any noise received at the input.
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2.42 Get Smart Torque
■ Class
■ RS-232 String
■ Returns
Get (in)
Get SmartTorque [CR]
OFF[0] or ON[0]
Description
This command returns the status for the Smart Torque feature of the
LT360. The returned string value is either OFF or ON.
This parameter controls the behavior of the stepper motor. When
SmartTorque is set ON, the motor is powered down to half the driving
power 2 seconds after each movement stops. Motor power is returned
to full (as controlled by the Maximum Torque setting) when the motor
starts again.
This feature takes advantage of the fact that the worm gear drive system
employed by the LT360 is irreversible. Meaning, the platter is selflocking at its current position. The load cannot rotate the platter itself.
Therefore, it is not necessary to maintain full power on the motor
merely to hold its current position when the platter is not in movement.
The use of SmartTorque greatly reduces the thermal heating in the
motor and driver circuitry, and produces a very efficient drive system.
Under most conditions and use, this feature should always be kept ON.
If a particular application demands that the motor power be kept
constant at all times, even when stationary (SmartTorque=OFF), then
the maximum torque should be to 70% or less to prevent excessive
heating. It is difficult to envision what kinds of applications would
require this behavior, but the option is available if needed.
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2.43 Get Display Polarity
■ Class
■ RS-232 String
■ Returns
Get (in)
Get DisplayPolarity [CR]
UNIPOLAR[0] or BIPOLAR[0]
Description
This command returns the mode for the Display Polarity of the LT360. The
returned string value is either UNIPOLAR or BIPOLAR.
This parameter changes how the LT360 represents the degree position on
the front display of the chassis, and in the Win32 software. When
DisplayPolarity is set to UNIPOLAR, the LT360 will display the position in the
range of 0 to 360 degrees. All position values are positive. When it is set to
BIPOLAR, the range will be 0 to ±180 degrees. Both positive and negative
values will be shown.
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2.44 Get Input Polarity
■ Class
■ RS-232 String
■ Returns
Get (in)
Get InputPolarity [CR]
UNIPOLAR[0] or BIPOLAR[0]
Description
This command returns the mode for the Analog Input Polarity of the
LT360. The returned string value is either UNIPOLAR or BIPOLAR.
This parameter changes how the LT360 interprets the DC voltage
received at the Analog Input connector. When InputPolarity is set to
UNIPOLAR, the LT360 will accept voltages in the range of 0.000 to
+3.600 volts. All position values are positive. When it is set to BIPOLAR, the range will be 0.000 to ±1.800 volts. Both positive and negative values are used.
Voltages higher than the allowable range for the selected mode are
invalid.
The LT360 has a scale factor of 10mV/deg for the analog input. The
range can be either unipolar (0 ... +3.600V) or bipolar (0 ... ±1.800V).
The input impedance of the analog input is 1M Ohm. Although the
input is an unbalanced BNC connector, the actually circuitry is differential. This helps to reject ground noise.
The input source must be very stable and of low noise. The LT360 has a
resolution of 0.1 degrees and therefore responds to changes of 1mV at
the analog input. When this input is enabled, the LT360 will sample the
input and move to the location as indicated by the voltage. After that
move is completed, it then samples the analog input again and moves
to the new position. Monitoring of the analog input is real time.
If you are not using the analog input, this input must be set OFF.
Otherwise the LT360 will be controlled by any noise received at the
input.
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2.45 Get Output Polarity
■ Class
■ RS-232 String
■ Returns
Get (in)
Get OutputPolarity [CR]
UNIPOLAR[0] or BIPOLAR[0]
Description
This command returns the mode for the Analog Output Polarity of the
LT360. The returned string value is either UNIPOLAR or BIPOLAR.
This parameter changes how the LT360 generates the DC voltage output at
the Analog Output connector. When OutputPolarity is set to UNIPOLAR,
the LT360 will produce voltages in the range of 0.000 to +3.600 volts. All
position values are positive. When it is set to BIPOLAR, the range will be
0.000 to ±1.800 volts. Both positive and negative values are produced.
The LT360 has a scale factor of 10mV/deg for the analog output. The range
can be either unipolar (0 ... +3.600V) or bipolar (0 ... ±1.800V). The output
impedance of the analog output is <200 Ohms. Although the output is an
unbalanced BNC connector, it is highly recommended that the input on the
other device be differential to reject ground noise. Since the smallest
resolution of the LT360 is 0.1 degree, the equivalent resolution in the output
is 1mV. The input impedance of the other device should be at least 100K
Ohm to prevent loading errors.
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2.46 Get Motor Home Check
■ Class
■ RS-232 String
■ Returns
Get (in)
Get MotorHomeChk [CR]
OFF[0] or ON[0]
Description
This command returns the status for checking stepper motor synchronization. The returned string value is either OFF or ON.
When MotorHomeChk is set ON, the firmware checks that the motor
returns to its home position after each movement. If disabled, no checking
is performed. If checking is enabled and the motor does not end its operation in the Home position, an error message is shown on the front panel
display.
The stepper motor produces a specific number steps for a given amount of
platter rotation. The LT360 utilizes microstepping for additional precision
control. One particular phase of the motor is designated as the Home
position. For any given platter rotation, the motor should always end in its
Home position.
In normal operation this error should never occur. If it does, the unit must
be powered off to clear the error, or this feature disabled. It is possible for
this error to be produced by noise in the stepper motor controller, or by the
load exceeding the torque capability thereby causing the motor to skip
steps.
If this error is shown repeatedly, either there is a problem internal in the
LT360 or the torque load is too great for the drive system.
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2.47 Get Revision Code
■ Class
■ RS-232 String
■ Returns
Get (in)
Get RevCode [CR]
nn[0]
Description
This command returns the revision code of the controller PC board, as
an ASCII code for the revision letter. For example, '65' = A.
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2.48 Get Output Mode
■ Class
■ RS-232 String
■ Returns
Get (in)
Get OutputMode [CR]
CONT[0] or START[0] or STOP[0]
Description
This command returns the operating mode for the Analog Output. The
returned string value is either CONT or START or STOP.
When CONT is the mode, the Analog Output will continuously follow the
platter position as it is moving. This is a real time output mode where the
analog output voltage always represents the current platter position.
When START is the mode, the Analog Output will only produce a single step
change output voltage representing the final destination position at the start
of the movement. For example, if the current position is 0.0 degrees and
the destination is 100.0 degrees, the Analog Output voltage will change
from 0.000V to 1.000V at the start of the movement.
When STOP is the mode, the Analog Output will only produce a single step
change output voltage representing the final destination position after the
movement stops. For example, if the current position is 0.0 degrees and
the destination is 100.0 degrees, the Analog Output voltage will remain at
0.000V during the movement and then change to 1.000V when the movement stops. The final output voltage changes 2 seconds after the platter
movemet stops.
If the movement is aborted before it reaches the destination, the output
voltage will be updated to the correct final value in all modes.
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LT360 ANALOG OUTPUT MODES
OUTPUT VOLTAGE
START
MODE
CONT
MODE
STOP
MODE
PLATTER MOVEMENT
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