西門(mén)子的S7-200的程序結(jié)構(gòu)
過(guò)程映像輸入/輸出（I/Q）、變量存儲(chǔ)器V、內(nèi)部存儲(chǔ)器位M、定時(shí)器T、計(jì)數(shù)器C等屬于全局變量。S7-200的程序組織單元(ProgramOrganizationalUnit，簡(jiǎn)稱(chēng)為POU)包括主程序、子程序和中斷程序。每個(gè)POU均有自己的64字節(jié)局部變量，局部變量只能在它所在的POU中使用。與此相反，全局變量可以在各POU中使用。
下面是子程序可以使用的局部變量：
1)TEMP(臨時(shí)變量)是暫時(shí)保存在局部數(shù)據(jù)區(qū)中的變量。只有在執(zhí)行該P(yáng)OU時(shí)，定義的臨時(shí)變量才被使用，POU執(zhí)行完后，不再保存臨時(shí)變量的數(shù)值。
2)IN是由調(diào)用它的POU提供的輸入?yún)?shù)。
3)OUT是返回給調(diào)用它的POU的輸出參數(shù)(子程序的執(zhí)行結(jié)果)。
4)IN_OUT是輸入_輸出參數(shù)，其初始值由調(diào)用它的POU傳送給子程序，并用同一變量將子程序的執(zhí)行結(jié)果返回給調(diào)用它的POU。
主程序和中斷程序的局部變量中只有臨時(shí)變量TEMP。
具有輸入、輸出參數(shù)和局部變量的子程序易于實(shí)現(xiàn)結(jié)構(gòu)化編程，對(duì)于長(zhǎng)期生產(chǎn)同類(lèi)設(shè)備或生產(chǎn)線的廠家尤為有用。這些廠家的編程人員為設(shè)備的各組件或工藝功能編寫(xiě)了大量的通用的子程序。即使不知道子程序的內(nèi)部代碼，只要知道子程序的功能和輸入、輸出參數(shù)的意義，就可以通過(guò)程序之間的調(diào)用快速“組裝”出滿足不同用戶要求的控制程序。就好像用數(shù)字集成電路芯片組成復(fù)雜的數(shù)字電路一樣。
子程序如果沒(méi)有輸入、輸出參數(shù)，它和調(diào)用它的程序之間沒(méi)有清晰的接口，很難實(shí)現(xiàn)結(jié)構(gòu)化編程。
子程序如果沒(méi)有局部變量，它和調(diào)用它的程序之間只能通過(guò)全局變量來(lái)交換數(shù)據(jù)，子程序內(nèi)部也只能使用全局變量。將子程序和中斷程序移植到別的項(xiàng)目時(shí)，需要重新統(tǒng)一安排它們使用的全局變量，以保證不會(huì)出現(xiàn)地址沖突。當(dāng)程序很復(fù)雜，子程序和中斷程序很多時(shí)，這種重新分配地址的工作量非常大。
如果子程序和中斷程序有局部變量，并且它們內(nèi)部只使用局部變量，不使用全局變量，因?yàn)榕c其他POU沒(méi)有地址沖突，不需作任何改動(dòng)，就可以將子程序移植到別的項(xiàng)目中去。
ALLEN BRADLEY 1492-CB2H100 CIRCUIT BREAKER ***NIB***
Lot 5 Allen Bradley Relays Contactors 100-A09ND3 3169
50 Allen Bradley Carbon Comp Resistors 100k 1/2W 5%
Lot (4) Allen Bradley 100-C23*10 Contactor w/ relay S3
Allen Bradley SLC 100 w/ expansion unit
100 Allen Bradley Carbon Comp Resistors 100k 1/2W 5%
Lot (9) Allen Bradley 100-C23*10 Contactor S3
Allen Bradley PLC SLC-100/150 1745-PCC cable (7ft)
ALLEN BRADLEY 100-B25ON*3 CONTACTOR 3 PHASE 600 VAC MAX
Allen-Bradley 100-C12EJ10 24V DC HZ 13 Contactor NEW
ALLEN BRADLEY 1336S-BRF100-AA?-EN4 SER E AC DRIVE
2098-DSD-HV100-?SE Allen Bradley 2098DSDHV100SE
ALLEN BRADLEY 100-B110N*3
FACTORY SEALED ALLEN BRADLEY 100S-C60D14C CONTACTOR
Allen Bradley Contactor 100-C12Z*10 Series A
Allen Bradley Contactor Starter 100 B180N*3 _ 208V Coil
LOT 3 ALLEN BRADLEY 100-C09*10 & 193-EA1DB CONTR. & REL
ALLEN BRADLEY 100-B110ND3 USPP 100B110ND3
ALLEN BRADLEY 140-MN-0630 100-C09*10 STARTER CONTACTOR
Allen Bradley 1756-EN2T -EtherNet 10-100M Comm Mod
ALLEN BRADLEY 100S-C30UDJ13BC USPP 100SC30UDJ13BC
100-B180ND3 Allen Bradley Contactor
Allen Bradley PLC SLC-100/150 USB 1745-PCC
Allen Bradley User's Manual 1745 SLC 100 Book Guide
100 Ohm 2W 5% Carbon Comp ALLEN BRADLEY resistor 25 ea.
ALLEN BRADLEY 100-A45N*3 STARTER *
Allen Bradley Bar Code Reader Wedge Access 2755-CE100
ALLEN BRADLEY 1492-W4 LOT OF 100 PCS TERMINAL BLOCK NEW
LOT OF 3 ALLEN BRADLEY CONTACTORS 100-A18NO2 12-05 L-1
Allen Bradley Resistors 100 pieces
ALLEN BRADLEY SIZE 4 STARTER 509-EOD 509-E0D 120V 100HP
Allen-Bradley 100-ETA30, Electronic Timing Module
Allen Bradley 100-C60*00 100C6000 Contactor NEW 110V
Allen Bradley Panel Mount Disconnect 1494F-N100 100 A
Allen Bradley Panel Mount Disconnect 1494V-DS100 100 A
Allen Bradley 1745-E101 1745E101 SLC 100 Expansion Unit
Allen-Bradley 100-A18ND3 AC Contactor
Allen Bradley 1398-DDM-005 | Ultra 100 Servo Drive
Allen Bradley Starter Auxillary 100-DNY42S **NIB**
Allen Bradley 100-D110 Contactor Non Reversing F1
Allen Bradley AB Starters IEC Bulletin 100-C37D10
ALLEN-BRADLEY SLC 1745-PT1 PROGRAMMER FOR 100/150 PLC
Allen Bradley PLC SLC-100/150 1745-PCC cable (12ft)
4 ALLEN-BRADLEY 1492-CB2G100 10-AMP CIRCUIT BREAKERS
ALLEN BRADLEY BAR CODE DECODER 100-240VAC 2755-DD1A
ALLEN BRADLEY 1492-CB1 1492-CB1G100 10 AMP CB
Allen Bradley 100-C30Z*00 Contactor Complete Device
ALLEN-BRADLEY 100S-C30D14C GUARD MASTER 110V COIL
ALLEN-BRADLEY CONTACTOR 24 VDC DIODE #100-C09DJ400
ALLEN-BRADLEY CONTACTOR 24 VDC DIODE #100-C09DJ400
ALLEN BRADLEY 100-C37-00/100-?C37*00 CONTACTOR **XLNT**
ALLEN-BRADLEY CONTACTOR 24 VDC DIODE #100-C09DJ400
ALLEN BRADLEY 100A 500L-DOD93 115-120V COIL CONTACTOR
ALLEN-BRADLEY CONTACTOR 24 VDC DIODE #100-C09DJ400
ALLEN-BRADLEY CONTACTOR 24 VDC DIODE #100-C09DJ400
ALLEN BRADLEY 100-SB10 AUXILIARY CONTACT BLOCK
ALLEN-BRADLEY CONTACTOR 24 VDC DIODE #100-C09DJ400
Allen Bradley AB IEC Contactor 100-C23D10
Allen Bradley Contactor 100-C16D10 16AMP 3POLE 120VAC
Allen Bradley 100-B180N*3 3Pole Contactor 225Amp 600VAC
Allen Bradley AB Starters IEC Bulletin 100-C16D10
Allen Bradley 100-A75N*3 3P Contactor 100A 600V 110-120
ALLEN BRADLEY 100-C23D300 CONTACTOR NEW IN BOX
Allen Bradley Contactor 100-C72*00 3P 100A 600V 110-120
Allen Bradley 100-A75N*3 3P Contactor 100A 600V 110-120
Allen Bradley 100 Ohm 2 W Linear Taper Potentiometer
Allen Bradley Non-Reversing Contactor 9A 100-C09D10
Allen Bradley 100-M09NZ243 CONTACTOR 24V 100-M09N*3
Allen Bradley Non-Reversing Contactors 100-C09D10 Pair
Allen Bradley Contactor 9amp 100-A09NJ3
Allen Bradley AB Starters IEC Bulletin 100-C43D10
ALLEN BRADLEY BREAKER 1492-CB2 G100 10 AMP 2 POLE
Allen Bradley 100-C09DJ10 Contactor 100C09DJ10 NEW
A-B Allen Bradley 1745-DEMO-1 SLC 100 P.C. PLC Trainer
Allen Bradley 100A45NC3 Contactor
5 Allen Bradley Carbon Comp Resistors 100k 1/2W 5%
Allen Bradley 85 Amp Contactor 100-C85D10 Used (3124)
Allen Bradley AB Starters IEC Bulletin 100-C09D10
Allen Bradley Circuit Breaker 1492-CB3H100 NIB (3008)
Allen Bradley 85 Amp Contactor 100-C85D10 Used (3124)
Allen Bradley 100-C12D10 Contactor
Allen-Bradley 100-B11ON*3 Contactor S10
Used/Remanufact?ured Allen Bradley 1336F-BRF100-AN?-EN
ALLEN BRADLEY 1336F DRIVE, 1336F-BRF-100-A?A-EN, PARTS
Allen Bradley 100-C09*10 Control Relays - Lot of 8
Allen-Bradley 100-A09NB3 AC Contactor New in Box!
lot Allen Bradley Contactors 100-C09Z*10
Allen Bradley Lighting Contactor Bul 100L-C20ND4 NNB
Allen Bradley SLC 100 Processor Unit 1745-LP101 PLC
3-ALLEN BRADLEY 100 SERIES CONTACTORS (GOOD CONDITION)
Allen Bradley Contactor 100-C85 85amp 24vdc coil
Allen Bradley SLC 100 150 Trainer Tool Crib Kit 1745PCC
Allen Bradley 100C43*00
Allen Bradley SLC 100 PLC Programmable Controller
ALLEN-BRADLEY 1745-TCAT CONTROL UNIT,SLC-100,15?0,KEY
Allen Bradley 100-B250N*3
Allen-Bradley-M?anual Starter & Contactor-Cat.#?140 &100
Allen Bradley AB Starters IEC Bulletin 100-C09ZJ10
ALLEN BRADLEY 1336F-CWF100-AN?-EN AC DRIVE
ALLEN BRADLEY DRIVE 100-HP 1336F-B100-AA-E?N-HCS2-LA1-L6
ALLEN BRADLEY 100-C43D00 CONTACTOR 115VAC COIL***XLNT**
1492-CB1G100 Allen Bradley 1492CB1G100 1492-CB1-G100
Allen Bradley Safety Contactor 100-D140 100S-D140D22C
Allen Bradley 10A 1-Pole Circuit Breaker 1492-CB1-G100
Allen Bradley 9A Contactor, 100-C09KD10
Allen Bradley 100-A60ND3 Ser. C Contactor 60 amp
Allen Bradley 100-M09N*3 /A 100-M09 Contactor
Allen Bradley 100-C09*10 Contactor S3
ALLEN BRADLEY 100-A09ND3 W/193-A1E1 RELAY
Allen Bradley AB Starters IEC Bulletin 100-C60D10
Allen Bradley Contactor 100-A18ND3 C Relay 193-BSC 10 B
Allen Bradley 100-K09KJ10 Mini Contactor
ALLEN BRADLEY CONTACTOR 100-A24NZ*3 115-VDC NIB
Allen Bradley 100-A18NKD3 AC Contactor Relay; *C2
Allen Bradley 100-FSD250 surge suppressors (2)
Allen Bradley 100k 5% 1/4watt Carbon Comp 50pc
ALLEN BRADLEY A31 MOTOR CONTACTOR AUXILLIARY 100-F
Allen Bradley 100 amp 3P Circuit Breaker 140M-I8 NEW
Allen Bradley 100-C12EJ10 Contactor 24VDC 100C12EJ10
Allen Bradley 100-C23Z*10 30A Motor Contactor C23
ALLEN BRADLEY AB TERMINAL BLOCKS 1492-J3 (LOTS OF 100)
ALLEN BRADLEY CONTACTOR Model 100 C09D
ALLEN BRADLEY 1492GH100 CIRCUIT BREAKER 10AMP 125VAC
ALLEN BRADLEY 100-M05NZ*3 100-M05NZ243 Mini Contactor
ALLEN BRADLEY CONTACTOR 100-B180N3 120V COIL 150HP 600V
ALLEN BRADLEY 100-C12*10 A CONTACTOR 12AMP 240VAC 3-POL
Allen Bradley 10A 2-Pole Circuit Breaker 1492-CB2-H100
ALLEN BRADLEY 1494V-H1 OPERATING HANDLE 30,60,100AMP
ALLEN BRADLEY 100-C37ZJ10 37 AMP 3 POLE CONTACTOR
Allen Bradley 100-A60N*3 60 Amp Contactor A60 Motor
Allen-Bradley 100-C09*10 Contactor
ALLEN BRADLEY Carbon Comp Resistor 100k 2 watt 10% (1)
ALLEN BRADLEY 100-A12ND3 STARTER 193-BSB42 OVERLOAD
1492-GH100 ALLEN BRADLEY SINGLE POLE CIRCUIT BREAKER
ALLEN BRADLEY CONTACTOR 100-A12ND3 OVERLOAD 193-BSB16
Allen Bradley Contactor 100-C09DJ10
Allen-Bradley 1492-CB1 Manual Motor Controller G100
ALLEN-BRADLEY 100 OHM CARBON COMP RESISTORS 50-1/4 Watt
Allen Bradley Contactor 100-MO5N*3 SER A M05 10E (3454)
Allen Bradley 1492-GH100 Series B Style GH AMP Breaker
ALLEN BRADLEY 24 VDC RELAY SERIES B 100-A30NZ 3
Allen Bradley AB Starters IEC Bulletin 100-C30D10
NEW Allen Bradley Contactor 100-C12D10
Allen Bradley Contactor 100-C60D*00 Series B
ALLEN BRADLEY Contactor # 100-C09D10 Ser A - New!
Allen Bradley 100-C72* Contactor 100-C7200
Allen Bradley RCR 100k 5% 1/4watt Carbon Comp 50pc
ALLEN BRADLEY 100 AMP MOTOR CONTACTOR 100-C72*00 C72B00
Allen Bradley 100-A18ND3 Series C Unit
Allen Bradley 100-C12D10 Ser. A Contactor
Allen Bradley 100-C12*10 /A 100-C12 Contactor
ALLEN BRADLEY (1494V-H1) A 100A OPERATING HANDLE NEW
Allen Bradley Contactor 100-A09NZ*3 24VDC w O/relay
ALLEN BRADLEY 100-A09NZ*3 CONTACTOR 9 A 600V 24VDC COIL
ALLEN BRADLEY 194R-NJ100P3 DISCONNECT SWITCH FUSED
ALLEN BRADLEY 100-C30Z D10 100-S B CONTACTOR
Allen Bradley Contactor 100-A09ND3 120/110 VAC (3570)
|
在線咨詢 
