Chapter4-Mang Thong Tin Cong Nghiep

7/30/2019 Chapter4-Mang Thong Tin Cong Nghiep

1/56

PROFIBUS Details

Date 06/22/00, Page 1

PROFIBUS Details

s

PROFIBUS DP Services (mng li profibus)

Master Class 2

Field Device (Slave)

Controls the Field Devices Parameterization Configuration

Cyclic Data Exchange Read Diagnostic

Read Diagnostic Set Station Address Read Configuration Read I/O

Take Over Control of 1 Slave Parameterization Configuration Data Exchange

Read Diagnostic Upload, Download (De)Activate Parameters (De)Activate Slaves Set Operation Mode

! Master Class1 and/or Class 2 and/or Slave can be implemented in one Device !

Master Class 1


2/56

PROFIBUS Details

Date 06/22/00, Page 2

PROFIBUS Details

s

Electronic... (continued)

Mi Slave/class 1 Master cn mt thit b lu tr dliu in t(= GSD file)

Tt c cc chc nng/c im/tham s ca thit b

u c xc nh trong GSD

Vn bn tp tin n gin(nh dng ASCII)

Thng tin u ra ca bng d liu c c bi cngc cu hnh

Tp tin c to ra t nh sn xut thit b

Trong website: www.profibus.com cung cp thm chobn

GSD cng c son tho to ra data sheets

GSD kim tra (c c trong phn son tho)

GSD th vin

GSD


3/56

PROFIBUS Details

Date 06/22/00, Page 3

PROFIBUS Details

s

Electronic... (continued)

Tp tin m rng nhn dng ngn ng

.gsd yu cu ti thiu (thng dng ngn ng l ting Anh)

Ngoi tp tin .gsd cn c cc tp tin khc:

English = .gse

French = .gsf

German = .gsg

Italian = .gsi

Portuguese = .gsp

Spanish = .gss

GSD


4/56

PROFIBUS Details

Date 06/22/00, Page 4

PROFIBUS Details

s

Cu lnh M t cc tham s(O)

nh ngha m rng cho cc thams (O)

D liu tng hp(M)

D liu lin quan ti thit btrng(M & O)

nh ngha cc knh vo ra

Electronic... (continued) - File Structure GSD

;

PrmText = ...

EndPrmText

#Profibus_DP

;

ExtUserPrmData = ...

EndExtUserPrmData

;

GSD_Revision = ...

;Slave-specification

Freeze_Mode_supp = ...

;

Module = ...

EndModule (M) = Mandatory (O) = Optional


5/56

PROFIBUS Details

Date 06/22/00, Page 5

PROFIBUS Details

s

File Structure... (continued) GSD

Phin bn theo tiu chun

Tn nh cung cp/nh sn xut

Tn thit b (hin th cng c cu hnh)

a ch duy nht cho mi sn phmBt buc cho thit b Class 1 v slaveBan hnh bi PTO

La chn giao thc (0=DP; 1=DP&FMS)

Kiu (0=Slave; 1=Master)

H tr chuyn i gi tr v thng s thigian lin quan


6/56

PROFIBUS Details

Date 06/22/00, Page 6

PROFIBUS Details

s

File Structure... (continued) GSD

H tr ng b ha d liu u vo

H tr ng b ha d liu u ra

Thit b t ng nhn bit gi tr truyn

a ch c th khng c t tPROFIBUS

Trm m rng

nh ngha chiu di cho cc trm module

D liu ti a chun on t thit b

S dng cng c cu hnh


7/56

PROFIBUS Details

Date 06/22/00, Page 7

PROFIBUS Details

s

Chuyn i d liu- SYNC/UNSYNC

ch bnh thng kt qu u ra nhn c t slave ASIC,ntrc tip cng slave Firmware ghi cc u ra vt l

Khi lnh iu khin SYNC c gi, u ra cui cnhn chuyn ti Slave Firmware sau b chn

Tr li hot ng bnh thng khi gp lnh UNSYNC

MASTER

Outputs to SlaveDATA x

Physical OutputsDATA x

Normal Mode

MASTEROutputs to Slave

DATA yPhysical Outputs

DATA xXSync Mode

MASTERSYNC

DATA xPhysical Outputs

DATA x

Sync Mode


8/56

PROFIBUS Details

Date 06/22/00, Page 8

PROFIBUS Details

s

Data Exchange - SYNC/UNSYNC

Outputs (x) to Slave 3DATA DATA

Physical Outputs = x

Outputs (z) to Slave 5DATA DATA

Physical Outputs = z

DATA DATA

Outputs (a) to Slave 3DATA x DATA x

Physical Outputs = x

X

Outputs (y) to Slave 4DATA DATA

Physical Outputs = yTime Lag Between DataAppearing at PhysicalOutputs of Different Slaves

Outputs (a) to Slave 4DATA y DATA y

Physical Outputs = y

XOutputs (a) to Slave 5

DATA z DATA zPhysical Outputs = z

X

After SYNC, Data Transferto Users Buffer IsBlockedOnlyBuffered in Receive Bufferfor All Slaves in GroupsIndicated

DATA DATA

Physical Outputs = DATA

Physical Outputs = DATA

SYNC Broadcast

Receive Buffer Users Buffer

Data is ImmediatelyTransferred to UsersBuffer & Physical OutputsAppear SimultaneouslyFor All Slaves in GroupsIndicated

x

y

z

x

y

z

DATA a

DATA a

DATA a


9/56

PROFIBUS Details

Date 06/22/00, Page 9

PROFIBUS Details

s

DATA a

Data Exchange - SYNC/UNSYNC

DATA a3

DATA a4

DATA a

DATA x

DATA y

DATA z

Physical Outputs = a


Physical Outputs = a5

SYNC Broadcast

DATA b

Data is ImmediatelyTransferred to UsersBuffer, Physical OutputsAppear Simultaneously& Slaves Go Back IntoNormal Mode For All Slavesin Groups Indicated

DATA b

UNSYNC Broadcast

Data is ImmediatelyTransferred to UsersBuffer & Physical OutputsAppear SimultaneouslyFor All Slaves in Groups

Indicated

Outputs (b) to Slave 3DATA a


XOutputs (b) to Slave 4

DATA a DATA aPhysical Outputs = a

XOutputs (b) to Slave 5 DATA a DATA a Physical Outputs = aX

Data Transfer to UsersBuffer Is BlockedOnlyBuffered in Receive Bufferfor All Slaves in GroupsIndicated

Receive Buffer Users Buffer

DATA a

DATA a

DATA a

DATA b

DATA b

DATA a

DATA aDATA b

DATA bPhysical Outputs = b

Physical Outputs = b

DATA b


10/56

PROFIBUS Details

Date 06/22/00, Page 10

PROFIBUS Details

s

PROFIBUS Demo


11/56

PROFIBUS Details

Date 06/22/00, Page 11

PROFIBUS Details

s

PROFIBUS Cu trc bn tin

SD: byte khi uLE: chiu di thng tin (DU) + DA, SA , FC, DSAP, SSAP LEr: chiu di thng tin nhc liDA: a ch ch(ni m tin nhn n)SA: a ch ngun (t tin nhn i)FC: m hm( FC=Type & Priority of Message)

DSAP: im ch im truy cp dch v(giao tip vi cng nhn)

SSAP: im ngun im truy cp dch v(giao tip vi cng o)FCS: byte kim sot liED: byte kt thc

= Included in FCS

SD LE LEr SD DA SA FC DSAP SSAP DU.. FCS ED

0x68 x x 0x68 x x x 0x3D 0x3E x .. x 0x16


12/56

PROFIBUS Details

Date 06/22/00, Page 12

PROFIBUS Details

s

PROFIBUS cu trc bc in

Start

Bit0

Each character is 11 bits(Start-, Stop-, (Even) Parity- and 8 Data bits)

Data

Bit0

LSB

Data

Bit1

Data

Bit2

Data

Bit3

Data

Bit4

Data

Bit5

Data

Bit6

Data

Bit7

MSB

Parity

Bit

Stop

Bit1


13/56

PROFIBUS Details

Date 06/22/00, Page 13

PROFIBUS Details

s

Cng truyn thng(Dch v truy nhp im)

Parameterization

Configuration

Output Data

Diagnostic Request

Is it?

You gotmail...


14/56

PROFIBUS Details

Date 06/22/00, Page 14

PROFIBUS Details

s

Cng truyn thng(tip tc)

It is:

Configuration

You gotmail...


15/56

PROFIBUS Details

Date 06/22/00, Page 15

PROFIBUS Details

s

FunctionDP Master DP Slave

Dec. Hex Dec. Hex

Data_Exchange - - - -

RD_Inp 62 3E 56 38

RD_Outp 62 3E 57 39

Slave_Diag 62 3E 60 3C

Set_Prm 62 3E 61 3D

Chk_Cfg 62 3E 62 3E

Get_Cfg 62 3E 59 3B

Global_Control 62 3E 58 3A

Set_Slave_Add 62 3E 55 37-

Cng truyn thng(tip tc)


16/56

PROFIBUS Details

Date 06/22/00, Page 16

PROFIBUS Details

s

Chuyn i d liu tc cao- Trnh t bt u

Power ON/Reset

Power ON/Reset of Master or Slave

Parameterization

Download of Parameters into the FieldDevice (selected during Configurationby the User)

I/O Configuration

Download of I/O Configuration into the

Field Device (selected duringConfiguration by the User)

Data ExchangeCyclic Data Exchange (I/O Data)and Field Device reports Diagnostics


17/56

PROFIBUS Details

Date 06/22/00, Page 17

PROFIBUS Details

s

Trnh t bt u(tip)

Power ON/Reset


Parameterization


I/O Configuration

Download of I/O Configuration into the

Field Device (selected duringConfiguration by the User)


Parameterization



18/56

PROFIBUS Details

Date 06/22/00, Page 18

PROFIBUS Details

s

7 BytesMandatory

Device Specific(Optional)

Up to 244 Bytes

Trnh t bt u- Tham s haSD LE LEr SD DA SA FC DSAP SSAP DU.. FCS ED

0x68 x x 0x68 x x x 0x3D 0x3E x .. x 0x16


19/56

PROFIBUS Details

Date 06/22/00, Page 19

PROFIBUS Details

s

Tham s ha(tip)

Tham s c truyn i khi cp ngun

7 byte bt buc dnh cho thit b trng

Qu trnh tham s ha: Response Monitoring Time

TSDR Time for Master/Slave Timing

Freeze/Sync Mode

Lock or Unlock Slave for this Master

Assignment to Group Master Address

Ident Number

Thi gian xc nhn ngn


20/56

PROFIBUS Details

Date 06/22/00, Page 20

PROFIBUS Details

s

Tham s ha(tip) - Mandatory

Lock Unlock Meaning

0 0 Min TSDR and User Parameters are allowed to be overwritten

0 1 DP-Slave is NOT locked for other Masters

1 0 DP-Slave is locked for other Masters; all parameters are accepted

1 1 DP- Slave is NOT locked for other Masters

Reserved

WD_ON (1=Response Monitoring (Watchdog) Activated)

Freeze_Req (1=Support of Freeze Mode Required)

Sync_Req (1=Support of Sync Mode Required)

Unlock (See Table below)

Lock (See Table below)

7 0Octet 1


21/56

PROFIBUS Details

Date 06/22/00, Page 21

PROFIBUS Details

s

WD_Fact_1

WD_Fact_2 (Watchdog (s)=10ms * WD_Fact_1 * WD_Fact_2)

TSDR (Time the field device waits before it responds)

PROFIBUS Ident Number (high byte)

PROFIBUS Ident Number (low byte)

Group_Ident (8 groups; bit x is set -> devices belongs to group x)

Tham s ha - Mandatory (tip)

Octet 2

Octet 3

Octet 4

Octet 5

Octet 6

Octet 7


22/56

PROFIBUS Details

Date 06/22/00, Page 22

PROFIBUS Details

s

Tham s ha(tip) thit b lin quan

Mi thit b s dng Octets 8 - 244 cho thit bmodule thng tin lin quan (e.g. thng tin khing)

V tr ca DIP thit b chuyn mch (v d nh thitlp phm vi o lng cho mt knh tng t)


23/56

PROFIBUS Details

Date 06/22/00, Page 23

PROFIBUS Details

s

Tham s ha(tip) v d GSD File


24/56


25/56

PROFIBUS Details

Date 06/22/00, Page 25

PROFIBUS Details

s

Simple and/or SpecialIdentifier Format

Up to 244 Bytes

Trnh t khi ng cu hnhSD LE LEr SD DA SA FC DSAP SSAP DU.. FCS ED

0x68 x x 0x68 x x x 0x3D 0x3E x .. x 0x16


26/56

PROFIBUS Details

Date 06/22/00, Page 26

PROFIBUS Details

s

Cu hnh(tip)

Cu hnh c gi mt ln sau bt ngun hoc reset

Master gi cu hnh ti Slaves

Bt k cu hnh thit b c th no

Cu hnh vo ra Slave confirms receipt with short acknowledge

Tha nhn cu hnh(Short Acknowledge E5h)

Kim tra hiu lc ca thng tin cu hnh


27/56

PROFIBUS Details

Date 06/22/00, Page 27

PROFIBUS Details

s

Cu hnh(tip) khung n gin

Chiu di d liu cho cc d liu u vohoc u ra (khng dnh cho nh0000=1 Byte/Word...1111=16 Bytes/Words

nh ngha d liu00=Special Format (see page 28)01=Input10=Output11=Input & Output

Size Data Unit (NOT for Special Format)0=Byte1=Word

7 0Identifier 1 (1 Byte per Module for Simple Format)

Tnh nht qun d liu(NOT for Special Format)0=Byte/Word1=Whole Length

Cu hnh d liu b sung (nh dng n gin hoc c bit)


28/56

PROFIBUS Details

Date 06/22/00, Page 28

PROFIBUS Details

s

Cu hnh(tip) v d cho khung n gin

Data Length1010=11 Words

Data Definition10=Output

Size Data Unit (NOT for Special Format)1=Word

Data Consistency (NOT for Special Format)0=Word

0 1 1 0 1 0 1 0


29/56

PROFIBUS Details

Date 06/22/00, Page 29

PROFIBUS Details

s

Configuration (continued) - Special Format

Length of Vendor Specific Data

0000=No Data0001-1110=1-15 Bytes1111=No Data

00=Special Format (FIXED)

Input/Output00=No I/O01=One Byte for Input Data Specification follows10=One Byte for Output Data Specification follows11=One Byte for Output & 1 Byte for Input Data Specification follows

7 0

Header

I/O DataSpecification

VendorSpecific Data

Additional Config Data(Simple or Special Format)Header


30/56

PROFIBUS Details

Date 06/22/00, Page 30

PROFIBUS Details

s

Configuration (continued) - Special Format

Data Length for Input or Output Data

000000=1 Byte/Word...111111=64 Bytes/Words

Size Data Unit0=Byte1=Word

Data Consistency0=Byte/Word1=Whole Length

7 0

Header

HeaderVendor

Specific DataAdditional Config Data

(Simple or Special Format)I/O Data

Specification


31/56

PROFIBUS Details

Date 06/22/00, Page 31

PROFIBUS Details

s

Configuration (continued) - Example Special Format

0 1 0 0 0 0 1 1 1 Byte for Input Data Specification & 3 BytesVendor Specific Data follow

1 0 1 0 0 1 0 036 Bytes of Input Data with Consistency overwhole Length

0 0 0 0 0 1 1 0

1 1 1 1 0 1 1 0

1 0 1 1 1 1 0 1

3 Bytes of Vendor Specific Information


32/56

PROFIBUS Details

Date 06/22/00, Page 32

PROFIBUS Details

s

Configuration (continued) - Example Telegram

= Simple Format

= Special Format

1stModule

2ndModule

3rdModule


33/56

PROFIBUS Details

Date 06/22/00, Page 33

PROFIBUS Details

s

Configuration (continued) - Example GSD File


34/56

PROFIBUS Details

Date 06/22/00, Page 34

PROFIBUS Details

s

Startup Sequence (continued)

Power ON/Reset


Parameterization


I/O Configuration

Download of I/O Configuration into theField Device (selected duringConfiguration by the User)




35/56

PROFIBUS Details

Date 06/22/00, Page 35

PROFIBUS Details

s

Application SpecificData

Up to 244 Bytes

Startup Sequence - Data Exchange Request

SD LE LEr SD DA SA FC DU.. FCS ED

0x68 x x 0x68 x x x x .. x 0x16


36/56

PROFIBUS Details

Date 06/22/00, Page 36

PROFIBUS Details

s


Up to 244 Bytes

Startup Sequence - Data Exchange Response


0x68 x x 0x68 x x 0x08 x .. x 0x16


37/56

PROFIBUS Details

Date 06/22/00, Page 37

PROFIBUS Details

s

Data Exchange (continued) - Example GSD File


38/56

PROFIBUS Details

Date 06/22/00, Page 38

PROFIBUS Details

s

Trnh t bt u(tip) chun on

Khi no master yu cu chun on?

Trc khi ti v tham s m bo thit b hintrng c sn

Trc khi vo ch trao i d liu xc nhn ccthng s v cu hnh v chc chn rng cc thit btrng sn sng

Trong qu trnh trao i d liu bt c khi no c

ch ra bi d liu trng


39/56

PROFIBUS Details

Date 06/22/00, Page 39

PROFIBUS Details

s

Diagnostic (continued)

Power ON/Reset

Parameterization

I/O Configuration

Data Exchange

Are you there?(Check whether field device is available)

Parameters & configuration ok?(Validation of download)

Are you ready for data exchange?

What happened?(Master fetches diagnostic as indicated by field

device)


40/56

PROFIBUS Details

Date 06/22/00, Page 40

PROFIBUS Details

s


Up to 244 Bytes

Diagnostic (continued) - How is it indicatedduring the Data Exchange?


0x68 x x 0x68 x x 0x0A x .. x 0x16

Field device raises red flag inData Exchange response


41/56


42/56

PROFIBUS Details

Date 06/22/00, Page 42

PROFIBUS Details

s

6 BytesMandatory

Device Related(Optional)

Up to 244 Bytes

Startup Sequence - ParameterizationSD LE LEr SD DA SA FC DSAP SSAP DU.. FCS ED

0x68 x x 0x68 x x x 0x3D 0x3E x .. x 0x16

Diagnostic (continued) - Response from Field Device

Identifier Related(Optional)

Channel Related(Optional)


43/56

PROFIBUS Details

Date 06/22/00, Page 43

PROFIBUS Details

s

Diagnostic (continued) - Mandatory

Diag.Station_Non_Exist (Field device doesnt answer; set by master)

Diag.Station_Not_Ready (Field device not ready for data exchange)

Diag.Cfg_Fault (Error in configuration data)

Diag.Ext_Diag (Field device reports extended diagnostic information)

Diag.Not_Supported (Requested feature not supported by field device)

Diag.Invalid_Slave_Response (Set by master)

7 0Octet 1

Diag.Prm_Fault (Error in parameter data, e.g. Ident Number)

Diag.Master_Lock (Field device controlled by another master; set by master)


44/56

PROFIBUS Details

Date 06/22/00, Page 44

PROFIBUS Details

s

Diagnostic - Mandatory (continued)

Diag.Prm_Req (Field device needs to be paramterized)

Diag.Static_Diag (Field device can not provide valid data)

always set to 1

Diag.WD_ON/OFF (Response monitoring in field device activated/de-activated)

Diag.Freeze_Mode (Field device is operating in FREEZE mode)

Diag.Sync_Mode (Field device is operating in SYNC mode)

7 0Octet 2

Reserved

Diag.Deactivated (Set by master)


45/56

PROFIBUS Details

Date 06/22/00, Page 45

PROFIBUS Details

s

Diag.Ext_Overflow (Too much extended diagnostic data)

Diag.Master_Add (Address of controlling master; FFh if none)

PROFIBUS Ident Number (High byte)

PROFIBUS Ident Number (Low byte)

Diagnostic - Mandatory (continued)

Octet 3

Octet 4

Octet 5

Octet 6

Reserved


46/56

PROFIBUS Details

Date 06/22/00, Page 46

PROFIBUS Details

s

00 (Fixed)

Diagnostic (continued) - Optional: Device Related

Header

Data length(including header)

Up to 62 bytes Device Related information

Meaning is manufacturer specific

Should be described in GSD file


47/56

PROFIBUS Details

Date 06/22/00, Page 47

PROFIBUS Details

s

Diagnostic Device Related (continued) - ExampleGSD File

Meaning: Bit 0 of the Device RelatedDiagnostic is set to 1 - Fieldvoltage missing!


48/56

PROFIBUS Details

Date 06/22/00, Page 48

PROFIBUS Details

s

01 (Fixed)

Diagnostic (continued) - Optional: Identifier Related

Header

Data length(including header)

Based on modular system

Each module has one identifier

No additional descriptionnecessary


49/56

PROFIBUS Details

Date 06/22/00, Page 49

PROFIBUS Details

s

Diagnostic Identifier Related (continued) - Example

0 1 0 0 0 1 0 0

0 1 0 0 0 0 0 1

0 0 0 0 0 0 0 1

Identifier Related Diagnostic; Length = 4 Bytes

1 0 0 0 0 0 0 0

Identifier 0 & 6 (Module 1 & 7) with Diagnostics

Identifier 8 (Module 9) with Diagnostics

Identifier 23 (Module 24) with Diagnostics


50/56

PROFIBUS Details

Date 06/22/00, Page 50

PROFIBUS Details

s

10 (Fixed)

Diagnostic (continued) - Optional: Channel Related

Octet 1

Identifier number

3 bytes per channel

Pre-defined error types

Vendor specific types possible

01 = Input10 = Ouput11 = Input/Output

Octet 2

Channel number

001 = Bit010 = 2 Bit011 = 4 Bit

Octet 3

Error type100 = Byte101 = Word110 = 2 Words

1-short circuit2-under voltage3-over voltage4-overload5-over temperature

6-wire break7-upper limit exceeded8-lower limit exceeded9-error10-15 reserved16-31 manufacturer specific


51/56

PROFIBUS Details

Date 06/22/00, Page 51

PROFIBUS Details

s

Diagnostic Channel Related (continued) - Example

1 0 0 0 0 1 0 0

0 1 0 0 0 0 0 1

0 0 1 0 0 1 1 0

Channel Related Diagnostic; Identifier 4 (Module 5)

1 0 0 0 0 1 1 1

Channel 1 (=Input) with Diagnostic

Bit organized; Wire Break

Channel Related Diagnostic; Identifier 7 (Module 8)

Channel 3 (=Output) with Diagnostic

Word organized; Manufacturer specific code

1 0 0 0 0 0 1 1

1 0 1 1 0 0 1 0


52/56

PROFIBUS Details

Date 06/22/00, Page 52

PROFIBUS Details

s

Trao i d liu(tip)- DP Master

4 ch hot ng chnh ca DP Master:

OFFLINEkhng hot ng

STOPtruyn thng mt master class 2 c th,khngc giao tip vi thit b trng

CLEAR - Master truyn thng vi thit b trng; dliu u ra c t 0 hoc di u ra = 0trong trng cc thit b trng c h tr tnh nng

Fail Safe OPERATEhot ng theo ch chun; vic trao

i d liu t master i vi thit b trng


53/56

PROFIBUS Details

Date 06/22/00, Page 53

PROFIBUS Details

s

Trao i d liu(tip) - DP MasterGlobal_Control in tn

Gi theo kiu qung b(= tin nhn cho tt c cc trm)

a ch n= 127

S dng trong CLEAR v OPERATE ti thng tin thitb trng ch hot ng hin ti ca Master

S dng tn hiu thay i ch hot ng t CLEARti OPERATE v ngc li

c s dng trong vic chn nhm cc thit btrng hot ng trong SYNC v/hoc FREEZE


54/56

PROFIBUS Details

Date 06/22/00, Page 54

PROFIBUS Details

s

Data Exchange (continued) - Global Control

Command Group Definition

Not used

CLEAR

UNFREEZE

FREEZE

UNSYNC

SYNC

Not used

SD LE LEr SD DA SA FC DSAP SSAP DU.. FCS ED

0x68 x x 0x68 0xFF x x 0x3A 0x3E x .. x 0x16

0 = all field devices addressed

Each bit = 1 addresses ONE group(8 different groups are possible)


55/56

PROFIBUS Details

Date 06/22/00, Page 55

PROFIBUS Details

s

Trao i d liu(tip) - DP Master AUTOCLEAR Tnh nng c th c xc nh trong qu trnh cu

hnh mng

Master t ng chuyn ch hot ng t

OPERATE sang CLEAR nu mt hoc nhiu thit btrng khng tr li trong mt khong thi gian xcnh

ch ra s thay i ch , Master gi mtGlobal_Control bc in vi lnh CLEAR

Vic chuyn i tr li OPERATE s ci t bi ngis dng/ng dng


56/56

PROFIBUS Details

Thanks for your attention!

Chapter4-Mang Thong Tin Cong Nghiep

Documents

Transcript of Chapter4-Mang Thong Tin Cong Nghiep