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SIO-2
Channel Serial Communications Board
SIO-2 Document Part Document Reference Document Issue Level Manual covers PCBs identified 0127-0001 0127-0001.Doc SIO-2 Rev.
rights reserved. part this publication reproduced, stored retrieval system, transmitted, form means, electronic, mechanical, photocopied, recorded otherwise, without prior permission, writing, from publisher. permission contact Blue Chip Technology. Information offered this manual correct time printing. Blue Chip Technology accepts responsibility inaccuracies. This information subject change without notice. trademarks registered names acknowledged.
Blue Chip Technology Ltd. Chowley Oak, Tattenhall Chester, Cheshire 9EX. Telephone 01829 772000 Facsimile 01829 772001.
Amendment History
Issue Level
Issue Date 12.05.89
Author L.P.
Amendment Details First approved issue. Update window front cover logo. 98/083
Contents
OUTLINE DESCRIPTION SPECIFICATIONS Electrical Specification Physical Specification Electromagnetic Compatibility (EMC). Specification START-UP GUIDE Computer Type Backing Software Disk. Selecting Correct Comms Port Addresses Installing card Making Right Connections. Software Disk. CONNECTING CHANNEL Connecting Serial Printer. Connecting Modem Connecting Another SIO-2 Card Connecting Mouse. CHANNEL ALTERNATIVE INTERFACES. RS422 Full Duplex Mode RS485 Half Duplex Mode. RS485 Multi-Drop Network Mode Milliampere Current Loop Mode. SIO-2 SOFTWARE COMMERCIAL DATA ACQUISITION PACKAGES APPENDIX Blue Chip Technology SIO-2 APPENDIX Standard Port Allocations Serial. Ports APPENDIX
Blue Chip Technology Ltd. 01270001.doc
Contents
Standard Port Allocations Serial. Ports APPENDIX Channel RS232 Only APPENDIX Adapter DTE. APPENDIX Channel RS232/422/485/Current Loop. APPENDIX Channel R232 Full Duplex Mode APPENDIX Connecting Another Device SIO-2 Channel Null Modem Cable APPENDIX Channel 20mA Current Loop Mode. APPENDIX Current Loop Full Duplex Connection Another SIO-2 APPENDIX SIO-2 Current Loop Half Duplex Point Point Connection Another SIO-2. APPENDIX Channel RS422/485 Full Duplex Mode APPENDIX Channel RS422 Full Duplex Connections Another SIO-2 APPENDIX Channel RS485 Half Duplex Mode (Multi Drop Mode) APPENDIX
01270001.doc Blue Chip Technology Ltd.
Contents
RS485 Half Duplex Connections Another SIO-2. APPENDIX RS485 Multidrop Network SIO-2 Cards. Connected APPENDIX Interrupt Link Setting Channels APPENDIX PC/XT/AT Port Address APPENDIX PC/XT Interrupt APPENDIX Interrupt APPENDIX SIO2TEST.BAS Test Connectors. APPENDIX Current Loop Simplex Connections Another SIO-2. Overview
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Outline Description
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OUTLINE DESCRIPTION
SIO-2 card allows serial communications between computers, printers, plotters, screen, controllers, instruments other device with serial interface. frist channel RS232 with programmable baud rate word format. second channel link selectable either RS232, RS422/485 (full duplex, half duplex, multi-drop) 20mA current loop. This gives compatibility with most standard serial interchange formats. SIO-2 designed provide flexible solution problems interfacing compatible with following standards: RS232/V24 full half duplex RS422 full duplex RS485 full duplex multi-drop RS485 half duplex multi-drop Milliampere current loop full duplex There channels designated Channel provides normal RS232 type comms port connected Cannon range connector rear panel. this connector Serial standard configured device. Channel provides normal RS232 interface standard pins connector also selected provide current loop, RS422 RS485 operation which appear different outs provide some protection from incorrect operation card. Channel also configured device. full connection details ever mode operation appears Appendix. installing SIO-2 card Amstrad 1512 1640 necessary remove bottom retaining screw type connector. This non-IBM standard back panel Amstrad.
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Specifications
SPECIFICATIONS Electrical Specification
Number Channels Interface Standards Channel RS232 Channel RS232 RS422 RS485 20mA Loop D.C. 150mA 500mW
Power requirement Power Dissipation
Physical Specification
Height Width Depth 107mm 15mm 132mm
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Specifications
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Electromagnetic Compatibility (EMC)
This product meets requirements European Directive (89/336/EEC) eligible bear mark. been assessed operating Blue Chip Technology Icon industrial However, because board installed variety computers, certain conditions have applied ensure that compatibility maintained. meets requirements industrial environment (Class product) subject those conditions. board must installed computer system which provides screening suitable industrial environment. recommendations made computer system manufacturer/supplier must complied with regarding earthing installation boards. board must installed with backplate securely screwed chassis computer ensure good metal-to-metal (i.e. earth) contact. Most problems caused external cabling boards. imperative that external cabling board totally screened, that screen cable connects metal bracket board hence earth. recommended that round screened cables with braided wire screen used preference those with foil screen drain wire. metal connector shells which connect around full circumference screen; they superior those which earth screen simple "pig-tail". Standard ribbon cable will adequate unless contained wholly within cabinetry housing industrial Ensure that screen external cable bonded good earth remote cable.
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Specifications
Failure observe these recommendations invalidate compliance.
Warning This Class product. domestic environment this product cause radio interference which case user required take adequate measures.
Specification
Blue Chip Technology Icon industrial fitted with this card meets following specification: Emissions: 55022:1995 Radiated Conducted Immunity: 50082-2:1995 incorporating Electrostatic Discharge 801-2:1991 Performance Criteria 50140:1993 Performance Criteria 801-4:1988 Performance Criteria Class Class
Radio Frequency Susceptibility
Fast Burst Transients
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Start-up Guide
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START-UP GUIDE Computer Type
SIO-2 Communications card designed work with correctly engineered compatible computers that provide standard compatible slot. your machine processor clock speed options suggest that perform installation tests SIO-2 with machine slow speed mode. Once correct operation card been established perform same tests higher clock rate. Unfortunately, although Blue Chip Technology makes every effort test products wide range machines, cannot guarantee that every called compatible" correct slot timing. Some latest 80386 based machines have facility their CMOS set-up program adjust number wait states used machine when accessing slot.
Backing Software Disk
SIO-2 card been supplied with floppy disk containing software demonstrations example drivers your use. important that make immediate backup this disk store suitably cool place. disk copy protected free make many backup copies like your departments use. disk copied onto blank floppy diskette same type with MSDOS command DISKCOPY single drive, DISKCOPY twin drive machine.
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Start-up Guide
wish copy files fixed disk (normally drive command MD\SIO-2 make suitable directory drive type CD\SIO-2 followed carriage return, SIO-2 floppy disk drive type COPY A:*.*C: followed carriage return. This will copy files from SIO-2 disk into correct directory drive
Selecting Correct Comms Port Addresses
before placing SIO-2 into your computer slot necessary establish correct addresses port card use. Sio-2 channels each which required different address set. Channel connected type connector back panel provides standard serial comms port. address channel controlled mini-dip header upper left hand side board. Channel connected type connector back panel provides serial port which work normal serial comms port RS232 current loop modes special comms port RS422//485 modes. port address channel controlled mini-dip header lower left hand side board. Appendices give example link settings normal serial ports COM1 COM2 plus usual ports unofficially allocated software hardware manufacturers COM3-COM8.
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Start-up Guide
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SIO-2 card normally issued from factory with channel COM1 channel COM2. quite likely that your computer will already have least serial port built into then this will usually occupying COM1 port address. There solutions this contention problem: Disable COM1/COM2 your your manual instructions. Change port addresses(and possibly interrupts) SIO-2 card. Appendices Ensure that other cards system devices same port address interrupt. Multiple SIO-2 cards same interrupts provided that software written support this.
Extra mini-dip green links provided with your package enable other address selections set.
Installing card
this first time that have installed peripheral card your should refer instructions hardware guide supplied with your machine information remove cover install devices into channel slot. SIO-2 placed available slot your compatible computer provided that there restriction placed upon slot manufacturer machine.
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Start-up Guide
Making Right Connections
Channel SIO-2 intended RS232 operation only. Channel supplied with links RS232 operation. wish other options channel then should follow link position connection diagrams supplied Appendix read appropriate section manual. type connection will need make channel SIO-2 will depend upon interface peripheral device wish connect
Software Disk
card used COM1 COM2 full duplex RS232/RS422 current loop modes from most existing software, RS485 half duplex mode requires user program board switch transmission this mode knowledge programming languages required. software disk supplied with SIO-2 contains number example ways driving card from various languages.
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Connecting Channel
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CONNECTING CHANNEL
Channel appears connector rear panel standard style RS232 serial port. Channel appears connector rear panel standard style RS232 current loop port also RS422 RS485 capability. Both channels used connect various peripherals such printers, modems mouse type pointing devices.
Connecting Serial Printer
When designed they considered data TERMINAL serial port design treated TERMINAL device. consequence this that connect another peripheral such printer must reverse signals between devices. When connecting serial printer necessary remember connect printer busy line (normally connector printer) DSR, connections appropriate connector wiring diagram suitable cable appears Appendix
Connecting Modem
connections this type equipment should normally direct signal signal case WS4000 following pins will make modem behave correctly.
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Connecting Channel
connector
Transmit data Receive data Data carrier detect Data terminl ready Digital ground
wish modem channel details converter cable appear Appendix Alternatively, create special direct cable from information pinout details.
Connecting Another SIO-2 Card
null modem cable concept (Appendix used again this connection should remembered that cable lengths over feet another interface such RS422/485 should considered.
Connecting Mouse
recommend Microsoft Serial Mouse with SIO-2. This comes with adapter both connections. There other mice market provided they designed work through standard serial port then they should present problem. experience problems, please refer supplier mouse first before contacting Blue Chip Technology supply complete range printers, mice, plotters external terminals etc. more details contact Sales Department.
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Channel Alternative Interfaces
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CHANNEL ALTERNATIVE INTERFACES RS422 Full Duplex Mode
SIO-2 RS422 full duplex mode refer Appendix connections link positions LKD. Appendix contains complete drawing SIO-2 card detailing locations various links board. important remember good quality shielded twisted pair cable this interface especially high baud rate (i.e. greater than 2400) being used. line drive receiver interface device used this mode 75176 this mode transmits data receives
RS485 Half Duplex Mode
N.B. Remember when using this mode good quality shielded twisted pair cable also install links enable 100ohm terminating resistors cards ends cable. Appendix Communication single twisted pair achieved with RS485 half duplex mode. Appendix details link settings connections this mode. used alone provide this interface consequently must switched from receive transmit back again receive when user wishes send message.
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Channel Alternative Interfaces
signal switch selected OUT1 from channel 164550 device. Link allows select appropriate signal. setting selected signal high state into Receive mode. RS485 half duplex very useful mode operation data acquisition message switching between based equipment Appendix details connect SIO-2 cards back back this mode.
RS485 Multi-Drop Network Mode
Appendix details couple multiple SIO-2 cards form multi-drop network which capable communication distances kilometre dependent upon baud rate. Please remember that protocol using this mode operation totally dependent upon user designing software avoid message collision provide some form packet based addressing system. N.B. Remember when using this mode good quality shielded twisted pair cable also install links (LKD5 LKD6) 100ohm terminating resistors cards ends cable. Appendix
Milliampere Current Loop Mode
Appendix details correct link settings connections current loop operation. IC13 IC14 provide driver receiver this mode. current loop mode been designed identical that used serial adapter. Thus cable designed this interface card should work properly when plugged into SIO-2. Appendix detail correct connections full half duplex operation this mode. Appendix details correct connections simplex operation this mode.
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SIO-2 Software
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SIO-2 SOFTWARE
drive SIO-2 depends totally upon type application propose for. card set-up COM1 COM2 then channels driven from with exception that half duplex RS485 requires some extra programming this mode. should remembered that under MS-DOS below there software support provided operating system more than first serial ports system (COM1 COM2). Other operating systems such PC-DOS PCMOS386 allow user make more than serial ports connection estra user terminals other printers etc. expected that OS/2 will same. Many language compilers have facility communications toolkits such Greenleaf comms library etc. card uses national Semiconductor NS16450N device which functionally equivalent original Intel 8250 device used early serial cards same chip used most manufacturers today. floppy disk which accompanies card contains number programs examples drive ports from different languages. There file called README.TXT disk which details latest updates programs.
COMMERCIAL DATA ACQUISITION PACKAGES
Blue Chip Technology SIO-2 used with almost data acquisition package that transmit receive information directly from serial port, package that driver support INTEL 8250 National Semiconductor NS164450chip. board installable standard serial PORT following packages: Blue Chip Technology SCAN1000
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SIO-2 Software
ASYST Macmillan Software Labtech notebook LOTUS Measure LOTUS Symphony Almost based communications package more details about these packages other data acquisition software, please contact Blue Chip Technology. Whilst every effort been taken ensure that information provided accurate, Blue Chip Technology cannot assume responsibility errors this manual their consequences. Should errors this manual detected, company would greatly appreciate being informed them. policy continuos product development operated, resulting contents this document being subject change without notice.
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Appendix
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APPENDIX Blue Chip Technology SIO-2
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Appendix
APPENDIX Standard Port Allocations Serial Ports
008H 010H 020H 040H 080H 100H 200H N.B. links removed 008H 010H 020H 040H 080H 100H 200H
008H 010H 020H 040H 080H 100H 200H 008H 010H 020H 040H 080H 100H 200H
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APPENDIX Standard Port Allocations Serial Ports
008H 010H 020H 040H 080H 100H 200H 008H 010H 020H 040H 080H 100H 200H
008H 010H 020H 040H 080H 100H 200H 008H 010H 020H 040H 080H 100H 200H
(N.B. LINKS VIEWED WITH CONNECTORS RHS)
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Appendix
APPENDIX Channel RS232 Only Connections
Digital Ground Output Input
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Appendix
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APPENDIX Adapter
Connections
Input
Input
Output
Output
Digital Ground
Digital Ground
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Appendix
APPENDIX Channel RS232/422/485/Current Loop
Connections
RCLR (Current Loop
TCLR (Current Loop (RS232) TCLD (Current Loop (RS232) Digital Ground (RS232) (RS232) (RS232) INPUT (RS232) Output (RS232)
(RS232)
RCLD (Current Loop Full/Half Duplex Full Duplex
Full Duplex
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Appendix
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APPENDIX Channel R232 Full Duplex Mode
Connections
Input
Input Digital Ground Input Input Output INPUT Output
Output
Link Positions
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Appendix
APPENDIX Connecting Another Device SIO-2 Channel Null Modem Cable
Connections SIO-2 Output
Printer Second SIO-2 Input Output
Input
Digital Ground
Digital Ground
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Appendix
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APPENDIX Channel 20mA Current Loop Mode
Connections
RCLR TCLR TCLD
RCLD
Link Positions
Optional Pull-up
Optional Pull-up
Optional Pull down
Optional Pull down
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Appendix
APPENDIX Current Loop Full Duplex Connection Another SIO-2
SIO-2 Non-Isolated (Active) Station
Connections
SIO-2 Isolated (Passive) Station
20mA P2/11 P2/18
Data
XMTR 4100
P2/7
P2/25
RCVR 4200
Data
20mA P2/25 P2/9
Data
RCVR 4200
P2/7
P2/11
XMTR 4100
Data
Link Settings SIO-2
Link Settings SIO-2
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Appendix
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APPENDIX SIO-2 Current Loop Half Duplex Point Point Connection Another SIO-2
SIO-2 Non-Isolated (Active) Station
Connections
SIO-2 Isolated (Passive) Station
20mA
P2/11 P2/7
P2/18
Data
XMTR 4100
P2/25
RCVR 4200
Data
P2/25
Data
RCVR 4200
P2/9 P2/18 P2/11
XMTR 4100
Data
Link Settings SIO-2
Link Settings SIO-2
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Appendix
APPENDIX Channel RS422/485 Full Duplex Mode
Connections Link Positions
(N.B. FITTED ENABLE 100R TERMINATOR RESISTORS LINES RESPECTIVELY)
N.B. APPLICABLE
Twisted Pair
Twisted Pair
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Appendix
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APPENDIX Channel RS422 Full Duplex Connections Another SIO-2
Connections
SIO-2 SIO-2
Sheilded Twisted Pair
Sheilded Twisted Pair
Sheilded Twisted Pair
Sheilded Twisted Pair
Link Positions
(NB: AND/OR ENABLE 100OHM RESISTORS TERMINATE CIRCUIT).
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Appendix
APPENDIX Channel RS485 Half Duplex Mode (Multi Drop Mode)
Connections Link Positions
OUT1 OUT1
SELECT SWITCHING SIGNAL
Twisted Pair
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Appendix
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APPENDIX RS485 Half Duplex Connections Another SIO-2
Connections
SIO-2 SIO-2
Sheilded Twisted Pair
Sheilded Twisted Pair
Link Positions Both SIO-2 Cards
OUT1
OUT1
(NB: LINK ENABLE TERMINATING RESISTOR EACH CIRCUIT)
SELECT SWITCHING SIGNAL
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Appendix
APPENDIX RS485 Multidrop Network SIO-2 Cards Connected
Connections
Station Station
Shielded Twisted Pair Cable
Link Positions Both SIO-2 Cards
(FIT ENBLE EACH CABLE
OUT1
OUT1
(OUT1/DTR CHANNEL SWITCHES RS485 CIRCUIT OFF).
SELECT SWITCHING SIGNAL
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Appendix
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APPENDIX Interrupt Link Setting Channels
Connections
Station Station
Shielded Twisted Pair Cable
Link Positions Both SIO-2 Cards
(FIT ENBLE EACH CABLE
OUT1
OUT1
(OUT1/DTR CHANNEL SWITCHES RS485 CIRCUIT OFF).
SELECT SWITCHING SIGNAL
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Appendix
APPENDIX PC/XT/AT Port Address
Address 000-01F 02-03F 040-05F 060-06F 070-07F 080-09F 0A0-0BF 0F8-0FF 1F0-1F8 200-207 278-27F 2F8-2FF 300-31F 360-36F 378-37F 380-38F 3A0-3AF 3B0-3BF 3C0-3CF 3D0-3DF 3F0-3F7 3F8-3FF controller 8237A-5 Interrupt controller 8259A Timer, 8254 Keyboard controller, 8742; control port CMOS RAM, Mask (Write) Page Register (Memory Mapper) Interrupt controller 8259 Clear (80287) busy Reset NPX, 80287 Numeric Processor Extension, 80287 Hard disk drive controller Reserved Reserved Parallel Printer Port Reserved Serial Port Reserved Reserved Parallel Printer Port Reserved SDLC Communications, Bisynchronous Reserved Bisynchronous Reserved Reserved Display Controller Diskette Drive Controller Serial Port
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APPENDIX PC/XT Interrupt Number Parity Timer Keyboard Reserved Asynchronous Communications (Secondary) SDLC Communications Asynchronous Communications (Primary) SDLC Communications Fixed Disk Diskette Parallel printer Usage
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Appendix
APPENDIX Interrupt
Level Microprocessor Interrupt Controllers CTLR CTLR Timer Output Keyboard (Output Buffer Full) Interrupt from CTLR Realtime Clock Interrupt Software Redirected (IRQ Reserved Reserved Reserved Coprocessor Fixed Disk Controller Reserved Serial Port Serial Port Parallel Port Diskette Controller Parallel Port Appendix Function Parity Channel Check
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Appendix
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APPENDIX SIO2TEST.BAS Test Connectors
Test connectors operate with SIO2TEST.BAS made making following links dummy connectors. 6-8-20 7-25 14-16 15-17 18-11
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Appendix
APPENDIX Current Loop Simplex Connections Another SIO-2
SIO-2 Non-Isolated (Active) Station SIO-2 Isolated (Passive) Station
Connections
20mA P2/11 P2/18
Data
XMTR 4100
P2/7
P2/25
RCVR 4200
Data
Link Settings Both SIO-2 Boards
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Appendix
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Overview
RS422/RS485 Most people have heard RS232C interface standard used computer communications. RS232C standard been successful uniting industry common interface, suffers from several limitations: Data transmission rate. Transmission distance. need connect ground together (unbalanced circuits).
RS422 established 1975. overcomes above problems provides fast, reliable balanced interface. Data transmission rate improved from 38.4 Kilobaud Megabaud; transmission distance increased from metres Kilometre circuit operates differential mode does require common ground connection. Note: transmission rate distance mutually exclusive. natural progression RS422 grow into network communications medium. point point communications concerned (see figure RS422 success possible high speed long distances. However, when true "bus topology" network (figure considered standard RS422 transceivers could cope with possibilities more than transmitter being active time. Figure Computer Computer
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Appendix
Figure
Computer
Computer
Computer
this situation occur, RS422 drivers would probably irreparably damaged. overcome this RS485 standard established. This allows possibility transmission "collision" from computers without damage occurring. RS485 industry standard cost Collision Sensing Multiple Access networks (CSMA) most popular device implementing this circuitry 75176 transceiver used Blue Chip Technology SIO-2. electrical details RS485 standard are: Differential Drive outputs driven opposite polarities time. maximum difference between output pins time volts minimum volts. input accept volts without damage being sustained. ability drive total transceivers connected instant (further transceivers accepted using repeaters). receiving sensitivity millivolts difference between inputs pins.
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volts volts common mode range permits ground difference volts between devices bus.
Considerations recommended that termination applied devices each bus. This termination typically ohms (this provided SIO-2 card effected fitting links card; manual), although depends characteristic impedance cable being used.
alternative method termination implemented below:
This effective under certain conditions does provide path between power rails devices.
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Appendix
layout topology subject phenomenon known "Transmission Line" effects. This affect signal strength various points distance from true device kept short possible there distinct chance that null points (extreme) signal strength (more likely) will appear.
Spurs length kept short possible
ideal where spur (stub) length exists. This achieved connecting joining device same point. Length cable determined transmission rate e.g.
Maximum Distance Kilometre Metres Metres Rate Kilobaud Megabaud Megabaud
(Using cable). cable used affect operation bus. Typically, should present nominal characteristic impedance ohms frequencies greater than kilohertz series loop resistance exceeding ohms.
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Whether cable twisted not, screened not, affect operation. Obviously, screening cable noise immunity increased should consider: Where screen attached advisable connect screen devices (remember RS232 cable cable crosstalk within sheath will increase. cable tray capacitance will increase excessive (depends length cable value/foot) affect performance. above should considered before network implemented.
There should more than volts difference between devices' ground potential bus. Beyond volts common mode range will exceeded devices will operate correctly. operate under these conditions introducing isolating transformer output circuitry transceivers. Problems experienced when implementing software protocol wire bus.
have stated before transceivers transmit same time. Therefore, mechanism must exist that each device knows when transmit freely. most common operation "Master Slave" method. This where device network deemed Master this device initiates transmissions communicating with each other devices turn offering opportunity transmit. This provides relatively simple solution means that Master will have high overhead controlling network. Also devices needing communicate devices other than Master carry larger overhead additional software complication.
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Appendix
more sophisticated protocol "Token Ring" method which works each device knowing which device next number, physical location) taking directly communication occurs between each adjacent pair devices improve flexibility network more difficult implement especially where devices switched time. Current Loop This method interfacing been used relatively long time now. reputation high integrity noisy environments ability isolate various devices within loop. weakness usually transmission rate where 9600 baud acknowledged high (although 19200 baud possible) this limits current loop speed activities. basis current loop interface that rather than voltage which transferred between devices with RS232, 485, current passed instead. This figure shows typical current loop circuit.
Local Remote
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constant current generator provides output from local device that external cabling passes through (light emitting diode) remote device. current back local device then switched provide modulation current either produce MARK SPACE bit. Considerations multiple devices connected daisy chain arrangement, necessary by-pass diodes each station case cable disconnected.
Station Station
doing current path ensure times regardless whether connection station made not. should remembered that positive voltage applied current generator device will limit number series diodes (either conventional). capacitance cable affect operation significantly. larger capacitance length cable lower maximum possible transmission rate.
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Appendix
Various permutations pull pull downs used (especially SIO-2) provide current path. Basically conventional current must flow from positive voltage negative voltage. This achieved many ways:
Local
Remote
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