Chapter 5 - AutomationDirect

Chapter 5 - AutomationDirect
F0-04AD-2 4-CH.
ANALOG VOLTAGE INPUT
CHAPTER
5
In This Chapter...
Module Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5–2
Setting the Module Jumpers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5–4
Connecting and Disconnecting the Field Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . .5–5
Wiring Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5–5
Module Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5–6
Special V-memory Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5–7
Using the Pointer in Your Control Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5–9
Scale Conversions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5–11
Module Resolution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5–14
Analog Input Ladder Logic Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5–15
Chapter 5: F0-04AD-2 4-Ch. Analog Voltage Input
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A
B
C
D
Module Specifications
5–2
The F0-04AD-2 Analog input module offers the
following features:
• The DL05 and DL06 will read all four channels in one
scan.
• The removable terminal block makes it possible to
remove the module without disconnecting the field
wiring.
• Analog inputs can be used as process variables for the
four (4) PID loops in the DL05 CPU and the eight (8)
PID loops in the DL06 CPUs.
• On-board active analog filtering and RISC-like
microcontroller provide digital signal processing to
maintain precise analog measurements in noisy
environments.
NOTE: The DL05 CPU’s analog feature for this module requires DirectSOFT32 Version 3.0c (or later) and
firmware version 2.10 (or later). The DL06 requires DirectSOFT32 version V4.0, build 16 (or later) and
firmware version 1.00 (or later). See our website for more information: www.automationdirect.com.
DL05/06 Option Modules User Manual; 7th Ed. Rev. A, 08/11
Chapter 5: F0-04AD-2 4-Ch. Analog Voltage Input
The following tables provide the specifications for the F0–04AD–2 Analog Input Module.
Review these specifications to make sure the module meets your application requirements.
Input Specifications
Number of Channels
Input Range
Resolution
Step Response
Crosstalk
Active Low-pass Filtering
Input Impedance
Absolute Maximum Ratings
Linearity Error (End to End)
Input Stability
Gain Error
Offset Error
4, single ended (one common)
0 to 5 VDC or 0 to 10 VDC (jumper selectable)
12 bit (1 in 4096)
10.0 mS to 95% of full step change
-80 dB, 1/2 count maximum*
-3 dB at 300Hz (-12 dB per octave)
Greater than 20K⏲
± 15V
± 2 counts maximum*
± 1 count *
± 6 counts maximum *
± 2 counts maximum*
±0.3% @ 25°C (77°F)
Maximum Inaccuracy
±0.6% 0 to 60°C (32 to 140°F)
Accuracy vs. Temperature
±100 ppm/°C typical
* One count in the specification tables is equal to one least significant bit of the analog data value ( 1 in 4096).
General Specifications
PLC Update Rate
16-bit Data Word
Operating Temperature
Storage Temperature
Relative Humidity
Environmental Air
Vibration
Shock
Noise Immunity
Power Budget Requirement
Connector
Connector Wire Size
Connector Screw Torque
Connector Screwdriver Size
4 input channels per scan
12 binary data bits
0 to 60° C (32 to 140° F)
-20 to 70° C (-4 to 158° F)
5 to 95% (non-condensing)
No corrosive gases permitted
MIL STD 810C 514.2
MIL STD 810C 516.2
NEMA ICS3-304
75 mA @ 5 VDC (supplied by base)
Phoenix Mecano, Inc. Part No. AK1550/8-3.5 - green
28 - 16 AWG
0.4 Nm
DN-SS1 (recommended)
DL05/06 Option Modules User Manual; 7th Ed. Rev. A, 08/11
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A
B
C
D
5–3
Chapter 5: F0-04AD-2 4-Ch. Analog Voltage Input
Setting the Module Jumpers
5–4
The position of the J2 jumpers determines the input signal levels. You can choose between
0–5VDC or 0–10VDC. The module ships with the jumpers installed connecting the pins. In
this position, the input signal level is 0–5VDC. To select 0–10VDC signals, use the jumper
selection chart located on the module. One or more channels can be selected for 0–10 VDC
input signal level by removing the jumper from the connecting pin of the appropriate channel.
This allows you to have some channels selected for 0–5 VDC signals and other channels selected
for 0–10 VDC signals.
J2 jumpers shown below are
configured as CH1 and CH4 set
for 0–10V, and CH2 and CH3
set for 0–5V.
J2
CH1
CH2
CH3 INPUTS
CH4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A
B
C
D
Refer to jumper selection chart.
ON=0–5V
RANGE
C14
WARNING: Before removing the analog module or the terminal block on the face of the module,
disconnect power to the PLC and all field devices. Failure to disconnect power can result in damage to
the PLC and/or field devices.
DL05/06 Option Modules User Manual; 7th Ed. Rev. A, 08/11
Chapter 5: F0-04AD-2 4-Ch. Analog Voltage Input
Connecting and Disconnecting the Field Wiring
Wiring Guidelines
Your company may have guidelines for wiring and cable installation. If so, you should check
those before you begin the installation. Here are some general things to consider:
• Use the shortest wiring route whenever possible.
• Use shielded wiring and ground the shield at the transmitter source. Do not ground the shield at both
the module and the source.
• Do not run the signal wiring next to large motors, high current switches, or transformers. This may
cause noise problems.
• Route the wiring through an approved cable housing to minimize the risk of accidental damage.
Check local and national codes to choose the correct method for your application.
A separate transmitter power supply may be required, depending on the type of transmitter
being used.
This module has a removable connector to make wiring and module removal easier. To remove
the terminal block, disconnect power to the PLC and the field devices. Pull the terminal block
firmly until the connector separates from the module.
The analog module can be removed from the PLC by folding out the retaining tabs at the top
and bottom of the module. As the retaining tabs pivot upward and outward, the module’s
connector is lifted out of the PLC socket. Once the connector is free, you can lift the module
out of its slot.
Wiring Diagram
Use the following diagram to connect the field wiring. If necessary, the terminal block can be
removed to make removal of the module possible without disturbing field wiring.
A n a l o g Input
4-CHANNELS
0–5V
0–10V
CH1+
CH2+
CH3+
CH4+
0V
0V
0V
0V
F0–04AD–2
DL05/06 Option Modules User Manual; 7th Ed. Rev. A, 08/11
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A
B
C
D
5–5
Chapter 5: F0-04AD-2 4-Ch. Analog Voltage Input
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A
B
C
D
Module Operation
5–6
Input Channel Update Sequence
The DL05 and DL06 read four channels of input data data during each scan. The CPU
supports special V-memory locations that are used to manage the data transfer. This is discussed
in more detail on the next page, “Special V–memory Locations”.
Scan
DL05/DL06 PLC
Read Inputs
Execute Application Program
Read the data
Store data
Scan N
Ch 1, 2, 3, 4
Scan N+1
Ch 1, 2, 3, 4
Scan N+2
Ch 1, 2, 3, 4
Scan N+3
Ch 1, 2, 3, 4
Scan N+4
Ch 1, 2, 3, 4
Write to Outputs
Analog Module Updates
Even though the channel updates to the CPU are synchronous with the CPU scan, the module
asynchronously monitors the analog transmitter signals and converts each signal into a 12-bit
binary representation. This enables the module to continuously provide accurate measurements
without slowing down the discrete control logic in the RLL program.
The module takes approximately 10 milliseconds to sense 95% of the change in the analog
signal. For the vast majority of applications, the process changes are much slower than these
updates.
NOTE: If you are comparing other manufacturers’ update times (step responses) with ours, please be aware
that some manufacturers refer to the time it takes to convert the analog signal to a digital value. Our analog
to digital conversion takes only a few microseconds. It is the settling time of the filter that is critical in
determining the full update time. Our update time specification includes the filter settling time.
DL05/06 Option Modules User Manual; 7th Ed. Rev. A, 08/11
Chapter 5: F0-04AD-2 4-Ch. Analog Voltage Input
Special V-memory Locations
Formatting the Module Data
The DL05 and DL06 PLCs have special V-memory locations assigned to their respective option
slots. These V-memory locations allow you to:
• specify the data format (binary or BCD)
• specify the number of channels to scan (4 channels for the F0-04AD-2)
• specify the V-memory locations to store the input data
DL05 Data Formatting
The table below shows the special V-memory locations which are used by the DL05 PLC for the
F0–04AD–2.
Analog Input Module
DL05 Special V-memory Locations
Data Type and Number of I/O Channels
Input Storage Pointer
V7700
V7701
Structure of V7700
Special V–memory location 7700 identifies that a F0-04AD-2 module is installed in the DL05
option slot and the data type to be either binary or BCD.
Loading a constant of 400 into V7700 identifies a
MSB
LSB
4 channel analog input module is installed in the
1 1 1 1 1 1 9 8 7 6 5 4 3 2 1 0
DL05 option slot, and reads the input data values
5 4 3 2 1 0
as BCD numbers.
Loading a constant of 8400 into V7700 identifies a
MSB
LSB
4 channel analog input module is installed in the
DL05 option slot, and reads the input data values
1 1 1 1 1 1 9 8 7 6 5 4 3 2 1 0
5 4 3 2 1 0
as binary numbers.
Structure of V7701
V7701 is a system V–memory location used as a pointer to a user V-memory location where the
analog input data is stored. The V–memory location loaded into V7701 is an octal number
identifying the first user V-memory location for reading the analog input data. This V–memory
location is user selectable. For example, loading O2000 causes the pointer to write Ch 1’s data
value to V2000, Ch 2’s data value to V2001, Ch 3’s data value to V2002, and Ch 4’s data value
to V2003.
You will find an example program that loads appropriate values to V7700 and V7701 on
page 5–9.
DL05/06 Option Modules User Manual; 7th Ed. Rev. A, 08/11
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A
B
C
D
5–7
Chapter 5: F0-04AD-2 4-Ch. Analog Voltage Input
DL06 Data Formatting
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A
B
C
D
5–8
Special V–memory locations are assigned to the four option module slots of the DL06 PLC.
The table below shows these V–memory locations which can be used for the F0–04AD–2.
Analog Input Module
DL06 Special V-memory Locations
Slot No.
Number of Channels
Input Pointer
1
V700
V701
2
V710
V711
3
V720
V721
4
V730
V731
Setup Data Type and Number of Channels
V–memory locations 700, 710, 720 and 730 are used to set the data format to be read in either
binary or BCD, and to set the number of channels that will be active.
MSB
LSB
For example, the F0–04AD–2 is installed in slot 1.
Loading a constant of 400 into V700 sets 4 channels
1 1 1 1 1 1 9 8 7 6 5 4 3 2 1 0
active, and the input data value is read as a BCD
5 4 3 2 1 0
number.
With the F0–4AD–2 in slot 1, loading a constant of
MSB
LSB
8400 into V700 sets 4 channels active, and the input
data value is read as a binary number.
1 1 1 1 1 1 9 8 7 6 5 4 3 2 1 0
Storage Pointer Setup
5 4 3 2 1 0
V-memory locations 701, 711, 721 and 731 are special locations used as storage pointers for the
analog input data. With the analog module installed in slot 4, the V–memory location loaded
in V731, for instance, is an octal number identifying the first user V-memory location to read
the analog input data. This V–memory location is user selectable. For example, loading O2000
using the LDA instruction causes the pointer to write Ch 1’s data value to V2000, Ch 2’s data
value to V2001, CH 3’s data value to V2002 and Ch 4’s data value to V2003.
You will find an example program that loads appropriate values to V700 and V701 on
page 5–10.
DL05/06 Option Modules User Manual; 7th Ed. Rev. A, 08/11
Chapter 5: F0-04AD-2 4-Ch. Analog Voltage Input
Using the Pointer in Your Control Program
DL05 Pointer Method
The DL05 CPU examines the pointer values (the memory locations identified in V7700 and
V7701) on the first scan only.
The example program below shows how to setup these locations. This rung can be placed
anywhere in the ladder program or in the initial stage if you are using stage programming
instructions.
This is all that is required to read the analog input data into V-memory locations. Once the data
is in V-memory you can perform math on the data, compare the data against preset values, and
so forth. V2000 is used in the example but you can use any user V-memory location.
SP0
LD
K400
Loads a constant that specifies the number of channels to scan and the
data format. The upper byte selects the data format (i.e. 0=BCD,
8=Binary) and the number of channels (set to 4 for the F0–04AD–2).
- or LD
K8400
OUT
V7700
LDA
O2000
OUT
V7701
The binary format is used for displaying data on some operator
interface units. The DL05 PLCs support binary math functions.
Special V-memory location assigned to the option slot contains the data
format and the number of channels to scan.
This loads an octal value for the first V-memory location that will be used
to store the incoming data. For example, the O2000 entered here would
designate the following addresses.
Ch1 – V2000, Ch2 – V2001, Ch3 – V2002, Ch 4 – V2003
The octal address (O2000) is stored here. V7701 is assigned to the
option slot and acts as a pointer, which means the CPU will use the octal
value in this location to determine exactly where to store the incoming
data.
DL05/06 Option Modules User Manual; 7th Ed. Rev. A, 08/11
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A
B
C
D
5–9
Chapter 5: F0-04AD-2 4-Ch. Analog Voltage Input
DL06 Pointer Method
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A
B
C
D
5–10
Use the special V–memory table below as a guide to setup the pointer values in the following
example for the DL06. Slot 1 is the left most option slot. The CPU will examine the pointer
values at these locations only after a mode transition, first scan only.
Analog Input Module
DL06 Special V-memory Locations
Slot No.
Number of Channels
Input Pointer
1
V700
V701
2
V710
V711
3
V720
V721
4
V730
V731
The F0–04AD–2 can be installed in any available DL06 option slot. Using the example
program from the previous page, but changing the V–memory addresses, the ladder diagram
below shows how to setup these locations with the module installed in slot 1 of the DL06. Use
the above table to determine the pointer values if locating the module in any of the other slot
locations. Place this rung anywhere in the ladder program or in the initial stage if you are using
stage programming instructions.
Like the DL05 example, this logic is all that is required to read the analog input data into Vmemory locations. Once the data is in V-memory you can perform mathematical calculations
with the data, compare the data against preset values, and so forth. V2000 is used in the example
but you can use any user V-memory location.
SP0
LD
K400
Loads a constant that specifies the number of channels to scan and the
data format. The upper byte selects the data format (i.e. 0=BCD,
8=Binary) and the number of channels (set to 4 for the F0–04AD–2).
- or LD
K8400
The binary format can be used for displaying data on some
operator interface units and the DL06 LCD display. The DL06
PLCs support binary math functions.
OUT
V700
Special V-memory location assigned to the first option slot contains the
data format and the number of channels to scan.
LDA
O2000
This loads an octal value for the first V-memory location that will be used
to store the incoming data. For example, the O2000 entered here would
designate the following addresses.
Ch1 – V2000, Ch2 – V2001, Ch3 – V2002, Ch 4 – V2003
OUT
V701
The octal address (O2000) is stored here. V701 is assigned to the
first option slot and acts as a pointer, which means the CPU will use
the octal value in this location to determine exactly where to store the
incoming data.
DL05/06 Option Modules User Manual; 7th Ed. Rev. A, 08/11
Chapter 5: F0-04AD-2 4-Ch. Analog Voltage Input
Scale Conversions
Scaling the Input Data
Many applications call for measurements in
engineering units, which can be more meaningful
than raw data. Convert to engineering units using
the formula shown to the right.
You may have to make adjustments to the formula
depending on the scale you choose for the
engineering units.
Units = A H – L + L
4095
H = High limit of the engineering
unit range
L = Low limit of the engineering
unit range
A = Analog value (0 – 4095)
For example, if you wanted to measure pressure (PSI) from 0.0 to 100.0 then you would have
to multiply the analog value by 10 in order to imply a decimal place when you view the value
with the programming software or a handheld programmer. Notice how the calculations differ
when you use the multiplier.
Analog Value of 2024, slightly less than half scale, should yield 49.4 PSI
Example without multiplier
Example with multiplier
Units = A H – L + L
4095
Units = 10 A H – L + L
4095
Units = 2024 100 – 0 + 0
4095
Units = 20240 100 – 0 + 0
4095
Units = 49
Units = 494
DL05/06 Option Modules User Manual; 7th Ed. Rev. A, 08/11
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A
B
C
D
5–11
Chapter 5: F0-04AD-2 4-Ch. Analog Voltage Input
The Conversion Program
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A
B
C
D
5–12
The following example shows how you would write the program to perform the engineering
unit conversion from input data formats 0–4095. This example assumes the raw input data read
at V2000 is in BCD format.
Note: this example uses SP1, which is always on. You could also use an X, C, etc. permissive
contact.
SP1
LD
V2000
When SP1 is on, load channel 1 data to the accumulator (for
a range of 0–1000).
MUL
K1000
Multiply the accumulator by 1000.
DIV
K4095
Divide the accumulator by 4095 (the module resolution).
OUT
V2100
Store the result in V2100.
DL05/06 Option Modules User Manual; 7th Ed. Rev. A, 08/11
Chapter 5: F0-04AD-2 4-Ch. Analog Voltage Input
Analog and Digital Value Conversions
Sometimes it is useful to convert between the signal levels and the digital values. This is
especially helpful during machine startup or troubleshooting. The following table provides
formulas to make this conversion easier.
Range
If you know the digital value
If you know the analog signal level
0 to 5V
A = 5D
4095
D = 4095 (A)
5
0 to 10V
A = 10D
4095
D = 4095 (A)
10
For example, if you are using the 0–10V range and
you need a 6V signal level, use this formula to
determine the digital value (D) that will be stored in
the V-memory location that contains the data.
D = 4095 (A)
10
D = 4095 (6V)
10
D = (409.5) (6)
D = 2457
DL05/06 Option Modules User Manual; 7th Ed. Rev. A, 08/11
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A
B
C
D
5–13
Chapter 5: F0-04AD-2 4-Ch. Analog Voltage Input
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A
B
C
D
Module Resolution
5–14
Analog Data Bits
The first twelve bits represent the analog data in binary format.
MSB
Bit
0
1
2
3
4
5
Value
1
2
4
8
16
32
Bit
6
7
8
9
10
11
Value
64
128
256
512
1024
2048
LSB
1 1 9 8 7 6 5 4 3 2 1 0
1 0
= data bits
Resolution Details
Since the module has 12-bit resolution, the analog voltage signal is converted into 4096 counts
ranging from 0–4095 (212). For example, with a 0 to 10V range, a 0V signal would be a count
value of 0, and a 10V signal would produce a count value of 4095. This is equivalent to a binary
value of 0000 0000 0000 to 1111 1111 1111, or 000 to FFF hexadecimal.
Each count can also be expressed in terms of the signal level by using the following equation:
0 – 10V
Resolution = H – L
4095
10V
H = high limit of the signal range
L = low limit of the signal range
0V
0
4095
The following table shows the smallest detectable signal change that will result in one LSB
change in the data value for each increment of the signal change.
Voltage Range
0 to 5V
0 to 10V
Signal Span
(H – L)
Divide By
Smallest Detectable
Change
5 volts
10 volts
4095
4095
1.22 mV
2.44 mV
DL05/06 Option Modules User Manual; 7th Ed. Rev. A, 08/11
Chapter 5: F0-04AD-2 4-Ch. Analog Voltage Input
Analog Input Ladder Logic Filter
PID Loops / Filtering:
Please refer to the “PID Loop Operation” chapter in the DL06 or DL05 User Manual for
information on the built-in PV filter (DL05/06) and the ladder logic filter (DL06 only) shown
below. A filter must be used to smooth the analog input value when auto tuning PID loops to
prevent giving a false indication of loop characteristics.
Smoothing the Input Signal (DL06 only):
The filter logic can also be used in the same way to smooth the analog input signal to help
stabilize PID loop operation or to stabilize the analog input signal value for use with an operator
interface display, etc.
WARNING: The built-in and logic filters are not intended to smooth or filter noise generated by improper
field device wiring or grounding. Small amounts of electrical noise can cause the input signal to bounce
considerably. Proper field device wiring and grounding must be done before attempting to use the filters
to smooth the analog input signal.
Using Binary Data Format
SP1
LDD
V2000
Loads the analog signal, which is in binary format
and has been loaded from V–memory location
V2000 – 2001, into the accumulator. Contact SP1
is always on.
BTOR
Converts the binary value in the accumulator
to a real number.
SUBR
V1400
Subtracts the real number stored in location
V1400 from the real number in the accumulator,
and stores the result in the accumulator. V1400
is the designated workspace in this example.
MULR
R0.2
Multiplies the real number in the accumulator by
0.2 (the filter factor), and stores the result in the
accumulator. This is the filtered value. The filter
range is 0.1 to 0.9. Smaller filter factors
increase filtering. (1.0 eliminates filtering.)
ADDR
V1400
Adds the real number stored in location V1400
to the real number filtered value in the
accumulator, and stores the result in the accumulator.
OUTD
V1400
Copies the value in the accumulator to
location V1400.
RTOB
Converts the real number in the
accumulator to a binary value, and
stores the result in the accumulator.
OUT
V2100
Loads the binary number filtered value from
the accumulator into location V2100 to use in
your application or PID loop.
DL05/06 Option Modules User Manual; 7th Ed. Rev. A, 08/11
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A
B
C
D
5–15
Chapter 5: F0-04AD-2 4-Ch. Analog Voltage Input
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A
B
C
D
5–16
NOTE: Be careful not to do a multiple number conversion on a value. For example, if you are using the pointer
method in BCD format to get the analog value, it must be converted to binary (BIN) as shown below. If you
are using the pointer method in Binary format, the conversion to binary (BIN) instruction is not needed.
Using BCD Data Format
SP1
LD
V2000
Loads the analog signal, which is in BCD format
and has been loaded from V–memory location
V2000, into the accumulator. Contact SP1
is always on.
BIN
Converts the BCD value in the accumulator
to binary.
BTOR
Converts the binary value in the accumulator
to a real number.
SUBR
V1400
Subtracts the real number stored in location
V1400 from the real number in the accumulator,
and stores the result in the accumulator. V1400
is the designated workspace in this example.
MULR
R0.2
Multiplies the real number in the accumulator by
0.2 (the filter factor), and stores the result in the
accumulator. This is the filtered value. The filter
range is 0.1 to 0.9. Smaller filter factors
increase filtering. (1.0 eliminates filtering.)
ADDR
V1400
Adds the real number stored in location V1400
to the real number filtered value in the
accumulator, and stores the result in the accumulator.
OUTD
V1400
Copies the value in the accumulator to
location V1400.
RTOB
Converts the real number in the
accumulator to a binary value, and
stores the result in the accumulator.
BCD
Converts the binary value in the accumulator
to a BCD number. Note: The BCD instruction
is not needed to PID loop PV (loop PV is a
binary number).
OUT
V1402
Loads the BCD number filtered value from
the accumulator into location V1402 to use in
your application or PID loop.
DL05/06 Option Modules User Manual; 7th Ed. Rev. A, 08/11
Was this manual useful for you? yes no
Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Download PDF

advertisement