BECKHOFF KL2521-0000 User Manual

Documentation for
KL2521-0000, KL2521-0024
1-Channel Pulse Train Output Terminals, RS422 / 24VDC
Version: 1.8 Date: 2009-05-06
Table of contents
1. Foreword 1
Notes on the documentation 1 Safety Instructions 2
2. Product Overview 3
Technical data 3
3. Functional description 4
Introduction 4 Resolution 5 Ramp function 5 Travel distance control 5 Output pattern 6 LED display 6 Connection 7
4. Access from the user program 10
Process Data 10 Register overview 11 Module-specific register description 12 Register communication 13 Control and Status Byte 15
5. Appendix 16
Support and Service 16
KL2521
Foreword
Foreword
Notes on the documentation
This description is only intended for the use of trained specialists in control and automation engineering who are familiar with the applicable national standards. It is essential that the following notes and explanations are followed when installing and commissioning these components.
Liability Conditions
The responsible staff must ensure that the application or use of the products describe d satisfy all the requirements for safety, including all the relevant laws, regulations, guidelines and standards. The documentation has been prepared with care. The products described are, however, constantly under development. For that reason the documentation is not in every case checked for consistency with performance data, standards or other characteristics. None of the statements of this manual represent s a guarantee (Garantie) in the meaning of § 443 BGB of the German Civil Code or a statement about the contractually expected fitness for a particular purpose in the meaning of § 434 par. 1 sentence 1 BGB. In the event that it contains technical or editorial errors, we retain the right to make alterations at any time and without warning. No claims for the modification of products that have already been supplied may be made on the basis of the data, diagrams and descriptions in this documentation.
Delivery conditions
In addition, the general delivery conditions of the company Beckhoff Automation GmbH apply.
Copyright
©
This documentation is copyrighted. Any reproduction or third party use of this publication, whether in
whole or in part, without the written permission of Beckhoff Automation GmbH, is forbidden.
KL2521 1
Foreword
Safety Instructions
State at Delivery
All the components are supplied in particular hardware and software configurations appropriate for the application. Modifications to hardware or software configurations other than those described in the documentation are not permitted, and nullify the liability of Beckhoff Automation GmbH.
Description of safety symbols
The following safety symbols are used in this documentation. They are intended to alert the reader to the associated safety instructions..
Danger
Attention
i
Note
This symbol is intended to highlight risks for the life or health of personnel.
This symbol is intended to highlight risks for equipment, materials or the environment.
This symbol indicates information that contributes to better understanding.
2 KL2521
Product Overview
Product Overview
A Signal - LED
B Signal - LED
+A
+B
+T
GND T,Z
Top view
T Signal - LED Z Signal - LED
- A
- B
+Z
Shield
GND Z,T Shield
+A
+B
- A
- B
+T +Z
Contact Assembly
Technical data
Technical data KL2521-0000 KL2521-0024
Number of outputs
Load type*
Rated load voltage*
Output current
Base frequency
Mark/space ratio
Resolution
Ramp calculation
Output cycle time
Delay time
Number of outputs
Input current
Electrical isolation
Current consumption from K-Bus
Input process image
Output process image
Configuration
Weight
Permissible relative humidity
Vibration / shock resistance
EMC resistance burst / ESD
Installation position
Type of protection
1 channel, 2 differential outputs (A, B) ohmic, opto-coupler, differential inputs 5 VDC internal 5 V ... 24 VDC external max. 0.05 A, RS485 specification max. 0.5 A 100 Hz ... 500 kHz, 50 kHz default 50% 16 bits over one word in the fieldbus, 24 bits usable altogether 2 ms / step 1 ms (synchronous to K-Bus)
0.6 ms after K-Bus cycle 2 (+T, +Z)
2.3 to 2.8 mA at 5 V to 30 V 500 V typ. 75 mA, max. 120 mA (load dependent) 24 bit I (16 bit in data, 8 bit status) 24 bit O (16 bit out data, 8 bit control) Via the Bus Coupler with KS2000 or the controller approx. 50 g 0°C ... +55°C (during operation) Permissible ambient temperature
-25°C ... +85° C (during storage) 95%, no condensation according to EN 60068-2-6 / EN 60068-2-27, EN 60068-2-29 according to EN 61000-6-2 / EN 61000-6-4 any IP20
(K-Bus / field potential output / input)
eff
*) depends on the hardware version pf the terminal, see chapter Connection
Default Mode Active Mode
RS485
+/- 5V
5…24V
Connection technique
+
5…24V
KL2521 3
Functional description
Functional description
process image By default, the KL2521 terminal occupies three bytes in the process image.
operating modes In addition to the FM (frequency modulation) operating mode, the KL2521
default setting The KL2521 is set to FM mode by default, with a basic frequency of 50 kHz
ramp function An internal ramp function raises/lowers the current frequency to the pre-set
Introduction
The KL2521 output terminal generates a binary signal with a variable frequency. The peripheral side of the electronics is electrically isolated from the internal K-Bus, and therefore also from the fieldbus. The output frequency can be adjusted. 16 bit values (signed integer) can be provided for this adjustment through the controller's process image. These values modify the output frequency from zero up to a pre-selected maximum frequency in equal increments - there are 32767 (15 bits) steps in each direction (right/left).
The mapping of the KL2521 can be set by means of the controller or by the Bus Coupler's configuration interface using the Beckhoff KS2000 configuration software.
can also be used to control stepper motors with pulse-direction control (frq. cnt pulse mode). Incremental transducer simulation is another operating mode. It is possible to connect an incremental transducer directly. Such inputs are present on many servo amplifiers and frequency converters.
and a resolution of 15 bits. The number of pulses output is read back into a 16 bit register. If the counter overflows a signal is sent to the controller. This is indicated by Status.3 (overflow) or Status.2 (under flow). In parallel with these two bits, Status. 6 is set as a general error bit. This makes the extension to more than 16 bits easier for the controller software to handle. The overflow can also be read from register 3 (internal 32 bit extension).
The counter can be reset to 0 through Control.5. By default, the counter is cleared by a rising edge (Feature.4 = 1). If Feature.4 = 0, the function is level-controlled. value defined by register R0 (lower word) and register R1 (higher word).
maximum frequency in accordance with the parameters set in registers 40/41. This is activated by FeatureBit.5. The base frequency for the ramp can be selected by FeatureBit.6. Status.1 is set while a ramp is being followed.
The releasing of Control.0 can be used to deactivate the function. During operation this can also be done by Control.1. In this way the user can change the base frequency during operation very quickly. Setting Control.0 = 1 (confirmed by Status.0) the values in registers 38/39 are used instead of those in registers 36/37 (Control.0 = 0).
The input signals T and Z are transferred directly from the terminal to the controller in the status byte (Status.4 / Status.5). The signals are not given any internal pre-processing.
If bit Feature.10 = 1, the counter is set by bit Control.5 to a
4 KL2521
Functional description
Resolution
The base frequencies are specified with their resolution of 1 Hz per bit
(GF1: registers 36, 37 or GF2: registers 38, 39). The terminal operates internally at 16 MHz with a resolution of 32 bits. This corresponds to a theoretical minimum step size of 0.0037 Hz/step over the entire frequency range. The output stage allows a maximum frequency of 500 kHz to be output.
Ramp function
The terminal offers a facility for soft starting and stopping. The ramp
gradient for starting can be set in register 40 with a precision of 10 or 1000 Hz/s (Feature.6). Register 41 performs the same function for stopping. The process data can be modified during transit of the ramp (Status.2), and the terminal then takes the new value as its target frequency.
Travel distance control
If the "travel distance control" function is active (Feature.9), then a rising
edge at Control.2 will result in drive to a fixed counter value. This value must previously be entered in register 0 (low word) and in register 1 (high word) at runtime. Time t
40. t
is reached at the maximum frequency f1 (register 2). Time t3 is
2
is specified by the ramp time constant in register
1
determined by the ramp time constant in register 41 with which the slowing down frequency f
(register 43) is achieved. When the given counter
2
contents have been reached, the terminal switches the frequency to zero. In order to travel to a destination with precision, it is necessary that the time constant for the falling ramp is greater than that of the rising ramp by a certain factor. This is necessary so that the slowing down frequency is reached before the final counter state, so that the terminal does not drive up to the end point at full speed. To explain in more detail: the KL2521 calculates the number of steps that are still to be taken in time t
from time t1 and from the number of steps that
2
have been taken. The calculation for stopping assumes the same number of steps as that found for starting up. The downward ramp must be a little steeper, approx. 10%, so that it is possible to reach the destination exactly in the remaining time t
+ t4 + t5. This relationship changes with the
3
maximum frequency.
KL2521 5
Functional description
operating modes The pattern of pulses is output through channels A and B. It is possible to
Output pattern
configure the necessary operating mode via feature register R32. The operating modes differ primarily between the positive logic modes 0, 1
and 2 and the negative logic modes 4, 5 and 6. Operating modes 2 and 6 simulate an incremental encoder, and permit
direct connection to an evaluation unit such as a servoamplifier or frequency converter with an incremental encoder input.
Operating mode Function
Rotation to the right Rotation to the left
Frequency modulation
positive logic ( BA 0 )
A
B
Pulse-direction control
positive logic ( BA 1 )
A
B
Incremental encoder
positive logic ( BA 2 )
A
B
Frequency modulation
negative logic ( BA 4 )
Pulse-direction control
negative logic ( BA 5 )
Incremental encoder
negative logic ( BA 6 )
Signal LEDs
watchdog When the watchdog is active (Feature.2 = 0!) the terminal will switch the
LED display
The 4 LEDs illuminate when the input and output signal levels are active. The illumination of the LEDs for the active frequency outputs A or B at higher frequencies can only be perceived as a glow at half brightness.
outputs off or will output a value stored in register 35 if no new process data is transferred to the terminal within 100 ms.
A
B
A
B
A
B
6 KL2521
Functional description
Connection
Connection of the inputs
Circuit examples for output to A. The same principles apply to output B.
The optically isolated inputs are protected from overload by a current limiter. The operating voltage can lie in the range between 5 V ... 24 V
DC
without any additional external circuitry. The GND connection is the common ground for the two inputs, T and Z.
The circuit diagram shows the internal circuitry of the two inputs:
+T +Z
3 mA
konstant
GND Z,T
Connection of the outputs
Outputs A and B on the KL2521 can be used with different types of
connection. An integrated DC/DC converter supplies the outputs stage of the two channels, A and B, with an electrically isolated 5 V power supply.
Connection to a RS485/RS232 receiver
The output can be operated as RS485 or as RS232 output. The circuit generates the necessary differential signals.
+A
- A
KL2521-0000
Connection to an optocoupler (without external power supply)
The outputs can be used for direct connection of an optocoupler. The output stage supplies the necessary output current using an internal 5 V power supply.
+A
220R
- A
KL2521-0000
KL2521 7
Functional description
i
Note
Check the hardware version
Connection to an optocoupler (with external power supply)
For connection to inputs with large internal impedances, an external power supply (of up to 24 V) can be used in order to create the necessary current.
The operation with external power supply depends on the hardware version of the terminal:
until hardware version 03 you can use the standard terminal KL2521-0000 for this.
from hardware version 04 this is only possible with special terminal KL2521-0024, that is especially optimized for this application! But because the KL2521-0024 misses the internal power supply (5 V), it is not suitable for connection of a RS232/485 receiver or an optocoupler without external power supply.
The firmware and hardware version (delivery state) can be found in the serial number printed at the side of the terminal.
Structure of the serial number: WW YY FF HH WW - week of production (CW, calendar week) YY - year of production FF - firmware version HH - hardware version
Example with ser. no.: 12 06 4F 03: 12 - week of production 12 06 - year of production 2006 4F - firmware version 4F 03 - hardware version 03
Until hardware version 03
+A
4K7
- A
KL2521-0000
7...24V
Instead of hardware version 04 (or higher) use special terminal KL2521-0024
+A
- A
KL2521-0024
4K7
7...24V
8 KL2521
Functional description
KL2521-0024: Connection to external electronics
For connection to external electronics pay attention that KL2521-0024's
terminal points A- of the first and B- of the second channel are internally connected to each other.
123
A+ B+
A+ B+
AB
A+ B+
KL2521-0024
A- B-
24V
KL2521-0024
A- B­AB
KL5151-0000
0V
24V
KL2521-0024
A- B­AB
KL5151-0000
0V
24V
This allows two channel connections of external electronics, if the KL2521-0024 switches the grounds of the external device, as shown in example 1.
The Beckhoff incremental encoder interface terminals KL5111, KL5121,
i
Note
KL5151 and KL5152 require the switching of the positive voltage. Because the terminal points A- and B- of KL2521-0024 are internally
bridged, the KL2521-0024 is not able to switch the two inputs of the KL5151-0000, shown in example 2, independently of each other. So this red crossed application doesn't make sense!
But you can use one channel of the KL2521-0024 to switch one channel of the KL5151-0000, as shown in example 3.
KL2521 9
Access from the user program
Access from the user program
Input format: Two's complement representation (integer - 1 corresponds to
(relative data)
(direct data) It is possible to enter the frequency directly (Feature.7).
relative data:
Process Data
0xFFFF) or sign / amount representation (Feature.3) (integer -1 corresponds to 0x8001)
The output frequency is specified within maximum resolution of 15 bits (the 16th bit is used to specify the direction). Negative process data results in rotation in the opposite direction. In this case, the internal counter counts to decreasing values.
The output frequency is based on the base frequency that is set in registers 36 to 39 and the process data (see table).
Output frequency = base frequency x process data / 32767 Highest resolution = 125 mHz
Example: Base frequency = 100,000 Hz (maximum selected output frequency) Process data = 0x00FF (255 Output frequency = 778.22 Hz
In this case the process data is multiplied by the factor contained in register 42, and directly written to the synthesis chip.
Output frequency = frequency factor x process data x 10 mHz Highest resolution = 10 mHz
Example: Frequency factor = 100 Process data = 0x00FF (255 Output frequency = 255 Hz
Process data Output value
Two's complement
Sign-amount
0x0000 0x3FFF 0x7FFF 0xC000
0x8000 0xBFFF 0xFFFF
)
dec
)
dec
0% DC 50% of the base frequency, rotation to the right 100% of the base frequency, rotation to the right 50% of the base frequency, rotation to the left
100% of the base frequency, rotation to the left 50% of the base frequency, rotation to the left 100% of the base frequency, rotation to the left
10 KL2521
Access from the user program
Register overview
Register set
Address Description Default value R/W Memory medium
R0 R1 R2 R3 R4
... R7 R8 R9
R10 R11 R12 R13 R14 R15 R16 R17
...
R30 R31 R32 R33 R34
R35 R36* R37* R38* R39*
R40
Target counter state (low word) Target counter state (high word) Maximum frequency Counter extension (high word) reserved ... Command register Terminal type Firmware version number Multiplex shift register Signal channels Minimum data length Data structure reserved Alignment register Hardware version number reserved ... reserved Code word register Feature register reserved reserved User's switch-on value Base frequency 1 (low word) Base frequency 1 (high word) Base frequency 2 (low word) Base frequency 2 (high word) Ramp time constant (rising,
0x0000 (0 0x0000 (0 0x0000 (0 0x0000 (0 0x0000 (0
dec dec dec dec dec
) ) ) )
) ... 0x0000 (0
dec
) 0x09D9 (2521 0x3446 (4F 0x0118 (280 0x0118 (280
ASCI
dec
dec
0x1818 (6468 0x0004 (4 0x0000 (0
dec dec
)
) variable 0x0003 (3 0x0000 (0
dec dec
)
) ... 0x0000 (0
dec
) variable 0x0030 (48 0x0000 (0 0x0000 (0 0x0000 (0
dec dec dec
dec
)
)
) 0xC350 (50000 0x0000 (0
dec
) 0x86A0 (34464 0x0001 (1
dec
) 0x03E8 (1000
)
dec
) ) )
)
dec
)
)
dec
)
dec
) R/W
dec
R/W RAM R/W RAM R/W RAM R RAM R ... R/W
...
RAM R ROM R ROM R ROM R ROM R ROM R ROM R R/W RAM R/W EEPROM R/W ... R/W
...
R/W RAM R/W EEPROM R/W R/W R/W EEPROM R/W EEPROM R/W EEPROM R/W EEPROM R/W EEPROM
EEPROM
see feature register)
R41
Ramp time constant (falling,
0x03E8 (1000
) R/W
dec
EEPROM
see feature register)
R42
Frequency factor (direct input,
0x0064 (100
) R/W
dec
EEPROM
(digit x 10 mHz)
R43
Slowing down frequency
0x0032 (50
) R/W
dec
EEPROM
(travel distance control)
...
reserved ... reserved
0x0000 (0 ... 0x0000 (0
) R/W
dec
) R/W
dec
...
...
R44
R61
*) The change of the base frequency needs a reset for activation.
KL2521 11
Access from the user program
Module-specific register description
R7: Command register [0x0000]
For a standard command to be executed, it is first necessary for the user code word, 0x1235, to be entered into
Command 0x7000: Restore Factory Settings
Entering 0x7000 in register R7 restores the factory settings for the following registers:
R32: R33: R34: R35: R36: R37:
0x0030 0x0000 0x0000 0x0000
0xC350
0x0000
(48
(0 (0 (0
(50000
(0
dec dec dec dec dec dec
R32: Feature register [0x0030]
The feature register specifies the terminal’s operating mode.
Feature bit no.
Bit 1 – Bit 0
Bit 2
Bit 3
Bit 4
Bit 5 Bit 6
Bit 7
Bit 8
Bit 9
Bit 10
Bit 12 – Bit 11 Bit 15 – Bit 13
pos. logic neg. logic [000] Operating mode Value range
000 100 001 101 010 110
-
0
1
1
1
0/1
0/1
0/1
1
0/1 [0] Counter
-
register R31.
) ) ) ) ) )
Description of the operating mode
No function [0] Watchdog timer active
The watchdog timer is switched on by default. Either the manufacturer's of the user's switch-on value is output if the watchdog overflows.
[0] Sign / amount representation [0] Sign / amount representation is active instead of two's-complement representation. (-1 = 0x8001)
[1] The counter is cleared by a rising edge in the Counter_Clear bit in the control byte
[1] Ramp function active [0] Ramp base frequency
0: 10 Hz/s 1: 1000 Hz/s
[0] Input mode 0: relative 1: direct
[0] Behavior when watchdog triggered 0: Manufacturer's switch-on value 1: User's switch-on value
[0] Travel distance control active
0: delete 1: set No function
Frequency modulation Pulse-direction control Incremental encoder
R38: R39: R40: R41: R42: R43:
0x86A0
0x0001 0x03E8 0x03E8
0x0064
0x0032
(34464
(1000 (1000
0 – 500 kHz
(1
(100
(50
dec dec dec dec dec dec
) ) ) ) ) )
12 KL2521
Access from the user program
Register communication
Register access via process data transfer Bit 7=1: register mode
When bit 7 of the control byte is set, the first two bytes of the user data are not used for process data transfer, but are written into or read out of the terminal’s register.
Bit 6=0: read Bit 6=1: write
In bit 6 of the control byte, you define whether a register is to be read or written. When bit 6 is not set, a register is read without modification. The value can be taken from the input process image.
When bit 6 is set, the user data is written into a register. The operation is concluded as soon as the status byte in the input process image has supplied an acknowledgement (see examples).
Bits 0 to 5: address The address of the register to be addressed is entered in bits 0 to 5 of the
control byte.
Control byte in the register mode
Bit 7 6 5 4 3 2 1 0 Name REG=1 W/R A5 A4 A3 A2 A1 A0
REG = 0: Process data transfer
REG = 1: Access to register structure W/R = 0: Read register W/R = 1: Write register A5...A0 = Register address A total of 64 registers can be addressed with the addresses A5...A0.
To the bus coupler
K-Bus
Control-/ status byte
C/S-bit 7
If control bit 6=0: read If control bit 6=1: write
Complex bus te rmina l
The control or status byte occupies the lowest address of a logical channel.
The corresponding register values are located in the following 2 data bytes (the BK2000 is an exception to the rule: here, an unused data byte is inserted after the control or status byte, thus setting the register value to a word limit).
User data
2 or mors bytes
H
L
If contr ol bit 7=0 : input/output
If contr ol bit 7=1 : register­configuration
If control bit 7=1: adress in the control bit 0-5
Terminal´s register set 64 words
63
0
H
L
KL2521 13
Access from the user program
Examples for Register Communication
Example 1 Reading register 8 in the BK2000 with a Kl3022 and the end terminal.
If the following bytes are transferred from the controller to the terminal,
Byte Name Value
Byte3 Byte2 Byte1 Byte0 Data OUT, low byte Data OUT, high byte Not used Control 0xXX 0xXX 0xXX 0x88
the terminal returns the following type designation (0x0BCE corresponds to
the unsigned integer 3022).
Byte Name Value
Byte3 Byte2 Byte1 Byte0 Data IN, low byte Data IN, high byte Not used Status 0xCE 0x0B 0x00 0x88
Example 2 Writing register 31 in the BK2000 with an intelligent terminal and the end
terminal. If the following bytes (user code word) are transferred from the controller to
the terminal,
Byte Name Value
Byte3 Byte2 Byte1 Byte0 Data OUT, low byte Data OUT, high byte Not used Control 0x35 0x12 0xXX 0xDF
the user code word is set and the terminal returns the register address with
the bit 7 for register access and the acknowledgement.
Byte Name Value
Byte3 Byte2 Byte1 Byte0 Data IN, low byte Data IN, high byte Not used Status 0x00 0x00 0x00 0x9F
14 KL2521
Access from the user program
Control and Status Byte
Control Byte in process data exchange
The Control Byte is sent to the terminal from the controller. It can be used
in register mode (REG = 1) or in process data exchange (REG = 0).
Bit 7 6 5 4 3 2 1 0
Name Reg_Access 0 Cnt_Clr 0 0 Go_Counter Ramp_Dis Freq_Sel
Bit Name Function
7 Reg_Access 5 Cnt_Clr
2 Go_Counter
1 Ramp_DisS
0 Freq_Sel
0: Register communication inactive (process data exchange) The contents of the counter is cleared or set (Feature.10) by this
bit. Any overflow or underflow bits that might be set are also cleared by this bit. The process can be edge triggered or level triggered (Feature.4).
If travel distance control is active (Feature.9), then a pre-set counter value is approached when the bit is set
Operation of the ramp function is cancelled, in spite of Feature.5 being active; if travel distance control is active, it is interrupted by this bit
Rapid change of the base frequency (only if the ramp function is inactive) 0: Base frequency 1 (registers 36 / 37) 1: Base frequency 2 (registers 38 / 39)
Status Byte in process data exchange
The Status Byte is sent from the module to the controller.
Bit 7 6 5 4 3 2 1 0
Name Reg_Access Error Input_Z Input_T Overflow Underflow Ramp_Active
Sel_Ack/
End_Counter
Bit Name Function
7 Reg_Access 6 Error 5 Input_Z 4 Input_T
3 Overflow
2 Underflow
1 Ramp_Active 0 Sel_Ack/
End_Counter
0: acknowledge for process data exchange General error bit, included with overflow/underflow End position reached The actual value when the device is connected does not agree
with the set value of the connected device. This bit is set if the 16-bit counter overflows (65535 -> 0). It is
reset when the counter exceeds one third of its measuring range (21845 -> 21846) or immediately an underflow occurs.
This bit is set if the 16-bit counter underflows (0 -> 65535). It is reset when the counter drops below two thirds of its measuring range (43690 -> 43689) or immediately an overflow occurs.
Ramp is currently being followed Confirms the change of base frequency. At activated travel distance control:
target counter value reached
The change of the base frequency needs a reset for activation.
KL2521 15
Appendix
Appendix
Support and Service
Beckhoff and their partners around the world offer comprehensive support and service, making available fast and competent assistance with all questions related to Beckhoff products and system solutions.
Beckhoff Support
Support offers you comprehensive technical assistance, helping you no only with the application of individual Beckhoff products, but also with other, wide-ranging services:
world-wide support
design, programming and commissioning of complex automation systems
and extensive training program for Beckhoff system components
Hotline: +49(0)5246/963-157 Fax: +49(0)5246/963-9157 e-mail: support@beckhoff.com
Beckhoff Service
The Beckhoff Service Center supports you in all matters of after-sales service:
on-site service
repair service
spare parts service
hotline service
Hotline: +49(0)5246/963-460 Fax: +49(0)5246/963-479 e-mail: service@beckhoff.com
You will find further support and service addresses on our Internet pages under http://www.beckhoff.com.
Beckhoff Headquaters
Beckhoff Automation GmbH Eiserstr. 5 33415 Verl Germany
Phone: +49(0)5246/963-0 Fax: +49(0)5246/963-198 e-mail: info@beckhoff.com
The addresses of Beckhoff 's branch offices and representatives round the world can be found on her internet pages: http://www.beckhoff.com .
You will also find further documentation for Beckhoff components there.
16 KL2521
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