OPTO 22 AC37 User manual

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AC37 HIGH-SPEED
COMMUNICATION ADAPTER CARD
USER’S GUIDE
Form 461-021028 — October, 2002
43044 Business Park Drive, Temecula, CA 92590-3614
Phone: 800-321-OPTO (6786) or 951-695-3000
Fax: 800-832-OPTO (6786) or 951-695-2712
www.opto22.com
Product Support Services:
800-TEK-OPTO (835-6786) or 951-695-3080
Fax: [phone]
E-mail: [email protected]
Web: support.opto22.com
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AC37 High-Speed Communication Adapter Card
ii
AC37 High-Speed Communication Adapter Card
Form 461-021028 — October, 2002
All rights reserved.
Printed in the United States of America.
The information in this manual has been checked carefully and is believed to be accurate; however, Opto 22 assumes
no responsibility for possible inaccuracies or omissions. Specifications are subject to change without notice.
Opto 22 warrants all of its products to be free from defects in material or workmanship for 30 months from the
manufacturing date code. This warranty is limited to the original cost of the unit only and does not cover
installation, labor, or any other contingent costs. Opto 22 I/O modules and solid-state relays with date codes of
1/96 or later are guaranteed for life. This lifetime warranty excludes reed relay, SNAP serial communication
modules, SNAP PID modules, and modules that contain mechanical contacts or switches. Opto 22 does not warrant
any product, components, or parts not manufactured by Opto 22; for these items, the warranty from the original
manufacturer applies. These products include, but are not limited to, the OptoTerminal-G70, OptoTerminal-G75,
and Sony Ericsson GT-48; see the product data sheet for specific warranty information. Refer to Opto 22 form
number 1042 for complete warranty information.
-----------------------------------------------
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All other brand or product names are trademarks or registered trademarks of their respective companies or
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AC37 High-Speed Communication Adapter Card iii
TABLE OF CONTENTS
Welcome.................................................................................................. v
About This Manual ......................................................................................................................... v
Document Conventions ................................................................................................................ v
AC37: IBM AT to Remote Bus Adapter Card ...................................... 1-1
Summary of Features: ................................................................................................................1-1
Address Selection:.......................................................................................................................1-2
Host CPU Interrupt Request Line Selection: ....................................................................... 1-3
RS-485 Serial Line Termination and Biasing: ....................................................................1-4
Examples:.......................................................................................................................................1-4
Installation:...................................................................................................................................1-5
Cable:.............................................................................................................................................. 1-5
Connector Pin Assignments.....................................................................................................1-5
Option Jumpers............................................................................................................................1-6
Register Definition ............................................................................... 2-1
TRANSMIT BUFFER REGISTER: ....................................................... OFFSET 0 - WRITE ONLY 2-1
RECEIVE BUFFER REGISTER: ........................................................... OFFSET 0 - READ ONLY 2-1
CARD IDENTIFICATION REGISTER: ................................................... OFFSET 7 - READ ONLY 2-1
BAUD RATE SELECT REGISTER ......................................................OFFSET 0 - READ/WRITE 2-2
INTERRUPT ENABLE REGISTER: ......................................................OFFSET 1 - READ/WRITE 2-3
INTERRUPT IDENTIFICATION REGISTER: ........................................... OFFSET 2 - READ ONLY 2-4
RESET CONTROL REGISTER: ...........................................................OFFSET 2 - WRITE ONLY 2-5
LINE CONTROL REGISTER: .............................................................OFFSET 3 - READ/WRITE 2-6
MODEM CONTROL REGISTER: ....................................................... OFFSET 4 - READ/WRITE 2-7
LINE STATUS REGISTER: ................................................................. OFFSET 5 - READ ONLY 2-8
MODEM STATUS REGISTER: ........................................................... OFFSET 6 - READ ONLY 2-9
External Interrupt Line, Remote I/O IRQ ............................................. 3-1
Modes of Operation ............................................................................ 4-1
Mode 0:..................................................................................................................................4-1
Mode 1:..................................................................................................................................4-1
Mode 2:..................................................................................................................................4-2
Mode 3:..................................................................................................................................4-2
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AC37 High-Speed Communication Adapter Card
TABLE OF CONTENTS
iv
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AC37 High-Speed Communication Adapter Card v
WELCOME
ABOUT THIS MANUAL
Thismanualisorganized as follows:
•Chapter 1: AC37: IBM AT to Remote Bus Adapter Card
•Chapter 2: Register Definition
•Chapter 3: External Interrupt Line, Remote I/O IRQ
•Chapter 4: Mode of Operation
DOCUMENT CONVENTIONS
•Boldtypefaceindicatestext to be typed. Unlessotherwise noted, such text maybe entered in upper or
lower case. (Example: “At the DOS prompt, typecd \windows.”)
•
Italic typeface indicates emphasis and isused for book titles. (Example:“See the OptoControlUser’sGuide
fordetails.”)
• Filenames appear in all capital letters.(Example: “Open the file TEST1.TXT.”)
• Keynames appear in small capital letters.(Example: “PressSHIFT.”)
• Keypresscombinations are indicated by plus signsbetweentwoor more key names. For example,SHIFT+F1
isthe result of holdingdown theSHIFT key, then pressing andreleasing theF1key. Similarly, CTRL+ALT+DELETE is
theresult of pressing andholding theCTRL andALT keys, then pressingand releasing theDELETE key.
• “Press”(or“click”)means press and release when used in referencetoamousebutton.
• Menucommandsaresometimesreferred to with the MenuàCommandconvention. For example, “Select
FileàRun”means to select theRuncommand from the File menu.
• Numberedlistsindicateprocedures to be followed sequentially.Bulleted lists (suchas thisone) provide
generalinformation.
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AC37 High-Speed Communication Adapter Card
WELCOME
vi
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AC37 High-Speed Communication Adapter Card 1-1
AC37: IBM AT TO REMOTE
BUS ADAPTER CARD
TheAC37 is acomputeradaptercard that provides aRS-4852or 4-wire communications link.Itisdesigned to allow
anyIBMATor compatible computer accesstotheOpto 22 Remote I/O Bus. TheRemoteBusis a standard RS-485
half-duplex(2 wire)serialcommunications link. TheAC37is primarily usedtoallow an ATto bethehost on aRemote
Bus link controlling a network of Opto 22 Remote I/O bricks, though it can also be used to monitor a link for
redundanthostapplications.
TheAC37 is designed toappearasastandard IBM serial ‘COM’ porttousersoftware. The CPU accessible registers
arearrangedand addressed in the same orderastheregisters of the 16,450 / 16,550UARTchipnormally used on
AT serial ports. While not all of the functions of the 16,550 are supported (e.g., modem control), all registers
necessaryforRemote Bus communications are configured inthesamemanner as a serial port.
SUMMARY OF FEATURES:
• Seriallink baud rates to 460,800
• Remotebusinterrupt input capability
• RS-4852-wire, half-duplex or 4-wire, full-duplex operation
• Serialand IRQ lines transient protected
• Serialand IRQ lines opticallyisolated to 2,500 VAC
• Upto 3,000 feet ofcable length using twistedpair cable at 115,200 baud
• Multidropcapability,RS-485 balanced line drivers
• Transmit, Receive, IRQ, andrunLED indicators
• TheAC37 has a CPU onit which allows it tohandle high speed serial communicationstasks for the host
CPU. The firmware program run by the AC37 CPU allows it to operate and appear to the host CPU as a
standardserial ‘COM’ port AC37CPU features include:
80C196KR16Bit High Performance Microcontroller
64 KB EPROM
Two 512 byte FIFOs for Data Transfers to/from Host CPU
CHAPTER 1
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AC37 High-Speed Communication Adapter Card
AC37: IBM AT TO REMOTE BUS ADAPTER CARD
1-2
ADDRESS SELECTION:
There are seven address jumpers on the AC37 labeled A3 through A9. These jumpers are used to select the
base address of the adapter card.The IBM PC-AT and compatibles only use 10 address lines for addressing I/O
locations. Since the AC37 card uses the three lower address lines directly, the upper seven (A3 through A9) are
used to decode the base address of the card.
Address jumpers A3 through A9 correspond to address lines A3 through A9. When a jumper is installed, the
jumper value is zero. A jumper not installed will indicate a one. When the address lines of the AT match the
jumper settings, the card is selected.
The base address must be less than 3FF Hex and have a zero or eight as the last digit. Care should be taken to
select a base address which will not conflict with other devices in the system.
Sample addresses and jumper settings are shown below:
Port Hex
Address
AGroup Jumpers IRQ
Group
Jumper
G4 Int
Select
Jumper
A9 A8 A7 A6 A5 A4 A3
COM1 3F80000000IRQ4IRQ15
COM2 2F80X00000IRQ3IRQ15
COM3 3E800000X0IRQ4IRQ15
COM4 2E8 0 X 0 0 0 X 0 IRQ3 IRQ15
OPTO COM3 348 0 0 X 0 X X 0 IRQ2 IRQ15
OPTO COM4 340 0 0 X 0 X X X IRQ5 IRQ15
OPTO COM5 248 0 X X 0 X X 0 IRQ10 IRQ15
OPTO COM6 240 0 X X 0 X X X IRQ11 IRQ15
X = Jumper installed
0 = Jumper not installed
Updated: 10-28-02
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AC37 High-Speed Communication Adapter Card 1-3
HOST CPU INTERRUPT REQUEST LINE SELECTION:
TheAC37allowsfor the selection of the interrupt request linewithagroupof jumpers labeled ‘IRQ GROUP’. All of
theinterruptsfoundin the Interrupt Identification Register can be routedtooneinterruptrequest line by installing
thejumper for that line. Onlyone jumper should be installedin this group, and careshould be taken to insurethat
noother device is using theselected interrupt request line.
* Donot install any jumpers here ifusing Cyrano software.
Seepage 1-6 if you needthese features.
AC37: IBM AT TO REMOTE BUS ADAPTER CARD
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AC37 High-Speed Communication Adapter Card
AC37: IBM AT TO REMOTE BUS ADAPTER CARD
1-4
RS-485 SERIAL LINE TERMINATION AND BIASING:
Theninejumperson the AC37 labeled ‘GROUP C’ are usedtoinstalltransmissionline terminators and/or tri-state
biasingresistorsasneeded. The function of each jumper is asfollows:
Jumper C0: Pull-up for TX/RX + line
Jumper C1: Terminator for TX/RX lines
Jumper C2: Pull-down for TX/RX - line
JumperC3: Pull-up for RX+ line
Jumper C4: Terminator for RX lines
Jumper C5: Pull-down for RX- line
Jumper C6: Pull-up for IRQ + line
JumperC7: Terminatorfor IRQlines
Jumper C8: Pull-down for IRQ - line
Terminating resistors should alwaysbe installed at bothENDS of an RS-485 transmissionline, and the linemust
haveonlyTWOends.Thebiasingresistorsareonlynecessaryatoneplace on the line and are typically installed at
thehost.
EXAMPLES:
Ifthe AC37 is communicating to aMisticModel200Processor(G4LC32) and is located at one endoftheline,install
C1, C3, C5, C6, and C8.
Ifthe AC37 isthehost(master) of a RemoteI/OBusand is located atoneendof the line,ALLgroupC jumpers should
beinstalled.
Ifthe AC37 is to bethe host of a RemoteI/O Bus and is NOTlocated at one end oftheline, install jumpers C0,C2,
C3, C5,C6, and C8only. Terminating resistors mustbe installed atboth ends ofthe transmission lines.
IftheAC37isto be a redundant or passive host which is monitoring a 2-wireRemote I/O link,and isnot at oneend
ofthe link, install jumpers on C3 andC5 and remove allother C group jumpers.
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AC37 High-Speed Communication Adapter Card
AC37: IBM AT TO REMOTE BUS ADAPTER CARD
1-5
Pin Description
1 TX/RX+ (2-wire) or TX+ (4-wire)
2 TX/RX- (2-wire) or TX- (4-wire)
3 COMMON
4 RX+ (4-wire)
5 RX- (4-wire)
6IRQ+
7 IRQ-
INSTALLATION:
After jumpering, the AC37 is ready for installation in any AT class (286, 386, or 486) machine. The AC37 requires
a 16-bit slot in the computer.
To install:
1) Remove computer cover
2) Insert AC37 in any 16-bit slot
3) Screw AC37 retainer bracket to case
4) Replace computer cover
CABLE:
RS-485 serial lines require twisted pair cable. Maximum cable length is 3,000 feet. The recommended cable
type is 2 twisted pair of 24 gauge conductors with a shield. Nominal impedance is 100 ohms and capacitance
is 12.5 picofarads per foot. Typical manufacturer part numbers are:
Manhattan Electric Cable M3475
Belden Wire and Cable 9,729
CONNECTOR PIN ASSIGNMENTS
The removable cable plug connector is Phoenix Contact p/n MC 1,5/7-STF-3,81.
Updated: 2/6/02
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AC37 High-Speed Communication Adapter Card
AC37: IBM AT TO REMOTE BUS ADAPTER CARD
1-6
OPTION JUMPERS
Option jumper 0 selects the AC37’s operation mode. Typically, mode 0 is used when data is received in the
communicationsbuffer on a character by characterbasis. Mode 0 enables the AC37tofunction like any standard
serialCOMport(16,550 UART,emulationmode0).Mode1isusedwhenacompletedataresponseisreceivedand
readyinthe communication buffer.
Remove jumper 0 to set the AC37 to mode 0 for connections to Mistic I/O bricks. If you are using the AC37 with
Mistic MMI or Cyrano to a Mistic controller, install jumper 0. This sets the AC37 to mode 1. For more about the
optionjumpers,seethe “Modes of Operation” section.
Option jumper 1 is reserved for future use.
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AC37 High-Speed Communication Adapter Card 2-1
REGISTER DEFINITION
TheCPUaccessibleregistersare addressed as follows:
TRANSMIT BUFFER REGISTER: OFFSET 0 - WRITE ONLY
Data written to the transmit register is put into a 512 byte deep FIFO ( First In First Out ) memory. The CPU on the
AC37 then reads and transmits the data out the RS-485 port.
RECEIVE BUFFER REGISTER: OFFSET 0 - READ ONLY
Thisregister is used to read datareceived on the RS-485 port. RemoteBusdata received is buffered ina512 byte
deepFIFO (First In First Out) memory.
CARD IDENTIFICATION REGISTER: OFFSET 7 - READ ONLY
Thisregisterwillalways read as 37 Hex, which may be used by software to identify the port as an AC37. Writing to
thisaddress will have no effect.
Offset from
Base Address DLAB * State Register Function Type
0 0 Receive Buffer Read Only
0 0 Transmit Buffer Write Only
01
Baud Rate
Select Read/Write
1 0 Interrupt Enable Read/Write
2X
Interrupt
Identification Read Only
2 X Reset Control Write Only
3 X Line Control Read/Write
5 X Line Status Read Only
6 X Modem Status Read Only
7X
Card
Identification Read Only
X = Don’t
Care
* The DLAB (Divisor Latch Access Bit) is bit 7 of the Line
Control Register.
CHAPTER 2
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AC37 High-Speed Communication Adapter Card
REGISTER DEFINITION
2-2
BAUD RATE SELECT REGISTER OFFSET 0 - READ/WRITE
Thisregisterisusedto select the baud rate for the RS-485 serial communications. This registercorresponds to the
leastsignificant byte ofthedivisorlatch in a 16,550UARTandmay be configured inthesamemanner with thesame
results.The DLAB bit in the Line Control Register must be set toa1beforethisregistercanbe accessed. If the Baud
Rate Select Register is configured to something other than the selections shown below, a default baud rate of
115,200will be set.
Desired Baud Rate Baud Rate Select
Register Setting
110 .........................................................................................17Hex
150 .........................................................................................00Hex
300 .........................................................................................80Hex
600 ........................................................................................ C0 Hex
1,200 .......................................................................................60Hex
2,400 .......................................................................................30Hex
4,800 .......................................................................................18Hex
9,600 ...................................................................................... 0CHex
19,200 .....................................................................................06Hex
38,400 .....................................................................................03Hex
57600 ......................................................................................02Hex
76,800 ..................................................................................... F0Hex
115,200 ...................................................................................01Hex
153,600 ................................................................................. F4Hex*
230,400 ................................................................................. F3Hex*
307,200 .................................................................................F5Hex *
460,800 .................................................................................F6Hex *
* Not Used with Mistic Remote I/O systems.
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AC37 High-Speed Communication Adapter Card 2-3
INTERRUPT ENABLE REGISTER: OFFSET 1 - READ/WRITE
This register is used to enable or disable the various types of host CPU interrupts which can be generated by the
AC37.Disabling an interrupt prevents it frombeing indicated as active in theInterruptIdentification Register and
fromactivating the host CPU interruptline. All other system functionsoperate in their normal manner, regardless
oftheir interrupt enable status. TheInterrupt Enable Register is definedbelow:
Bit 0: Received Data Available Interrupt Enable
When set to a logic 1, a received data available interrupt is generated whenever the
Receive Data Available bit is set in the Line Status Register. Refer to the description of
the Receive Data Available bit in the Line Status Register.
Bit 1: Transmit Buffer Register Empty Interrupt Enable
When set to logic 1, a transmit buffer empty interrupt is generated whenever the
transmit FIFO is ready to accept data. Refer to the description of the Transmit Buffer
Empty flag (bit 5) in the Line Status Register.
Bit 2: Receiver Line Status Interrupt Enable
When set to a logic 1, a receiver line status interrupt is generated upon a receive buffer
overrun error or a framing error. A receive buffer overrun error occurs when a data byte
is received while the receive FIFO is full. A framing error occurs if a stop bit was not
received at the appropriate time.
Bit 3: Modem Status Interrupt Enable
When set to a logic 1, a modem status interrupt is generated when the IRQ line of the
Remote Bus is activated. Since the AC37 has no modem support, the Remote Bus IRQ
line is directed through what is normally the CTS status bit.
Bits 4–7: Not Used
These bits are not used. They cannot be written to and will always read as zero.
REGISTER DEFINITION
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AC37 High-Speed Communication Adapter Card
REGISTER DEFINITION
2-4
INTERRUPT IDENTIFICATION REGISTER: OFFSET 2 - READ ONLY
This register can be read to determine if any interrupts are currently pending, and if so, what type. The AC37
prioritizes interrupts into the same four levels that the 16,550 UART does. The interrupt order of priority is:
1) Receiver LineStatus
2) Receive DataAvailable
3) TransmitBuffer Empty,and 4) Modem Status.The Interrupt ID Registerbits are defined below:
Bit 0: When this bit reads as a logic 0, an interrupt is pending and the contents of the Interrupt
ID Register can be used to vector to the appropriate interrupt service routine.
Bits 1–2: These two bits are used to identify the highest priority interrupt pending. The four types
are identified per the table below.
Bits 3–7: These bits are not used and will always read as logic 0.
A Line Status Interrupt is generated by either a receive buffer overrun or framing error. Refer to the Line Status
Register definition for a description of these errors. A Line Status Interrupt is cleared by reading the Line Status
Register.
AReceive Data Available Interrupt is generatedwhenever the Receive Data Available bitisset in the Line Status
Register. This interrupt is cleared by reading all data from the receive buffer or by resetting the FIFO. Refer to the
descriptionof the Receive DataAvailable flag (bit 0) inthe Line Status Register.
A Transmit Buffer Empty Interrupt is generated whenever the transmit FIFO is ready to receive data. Refer to the
descriptionof the TransmitBuffer Empty flag (bit 5) in the Line Status Register.
AModemStatusInterrupt is generated by the Remote Bus IRQ line being active. Since the AC37 is not intended for
use with modems, the Remote Bus IRQ line is directed through what is normally the CTS bit on the 16,550 UART.
Thisinterrupt is cleared by deactivatingthe Remote Bus IRQ line.
Bit 2 Bit 1 Bit 0 Priority Interrupt Type
0 0 1 No Interrupt Pending
1 1 0 Highest Line Status Interrupt
1 0 0 Second Receive Data
Available
0 1 0 Third Transmit Buffer Empty
0 0 0 Fourth Modem Status
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AC37 High-Speed Communication Adapter Card
REGISTER DEFINITION
2-5
RESET CONTROL REGISTER: OFFSET 2 - WRITE ONLY
This register is used to control the reset functions of the AC37. The bits of the Reset Control Register have the
followingfunctions:
Bit 0: Not Used
Bit 1: Receive FIFO Reset
Writing a logic 1 to this bit will reset the receive FIFO. All data in the FIFO will be
cleared and it’s pointers reset to 0. Data being shifted into the receiver is not affected.
This bit is self clearing and it is not necessary to write a logic 0 afterward.
Bit 2: Transmit FIFO Reset
Writing a logic 1 to this bit will reset the transmit FIFO. All data in the FIFO will be
cleared and it’s pointers reset to 0. Data being shifted out of the transmitter is not
affected. This bit is self clearing and it is not necessary to write a logic 0 afterward.
Bit 3: Not Used
Bit 4: CPU Reset
To reset the AC37 CPU, write a logic 1 to Bit 4 and verify the DLAB bit in the Line
Control is set to 1. This will have the same affect as cycling power to the AC37. Both
receive and transmit FIFOs are also reset. Baud Rate, Interrupt Control and Line Control
registers will be cleared and need reconfiguring by the host CPU. Since the reset cycle
can take two seconds, the host CPU should not try to reconfigure the AC37 registers
until 2 seconds after initiating a reset. This bit is self clearing and it is not necessary to
write a logic 0 afterward.
Bit 5: Not Used
Bit 6: Not Used
Bit 7: Not Used
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AC37 High-Speed Communication Adapter Card
REGISTER DEFINITION
2-6
LINE CONTROL REGISTER: OFFSET 3 - READ/WRITE
This register is used to select the format of serial communications data. The bits in the Line Control Register are
definedassuch:
Bits 0 and 3: Word Size Select
These two bits specify the number of bits in each serial character sent or received. The
AC37 does not support all of the various word sizes that the 16,550 UART does, but the
most commonly used data formats are supported and are selected using the settings
shown below:
Bit 1: Not Used
Bit 2: Not Used
Bit 4: Address-/Data Select
This bit controls the state of the 9th data bit when the 9 bit mode is selected. When
communicating to a Remote I/O brick using binary protocol, this bit determines if the
next byte written to the transmit FIFO will be interpreted as an address or data byte. If
bit 4 is set to a logic 0, the 9th bit of data written to the transmit FIFO will be set to a
logic 1 when transmitted, and will be interpreted as an address byte by the Remote I/O.
Conversely, if bit 4 is set to a logic 1, the 9th bit of data written to the transmit FIFO will
be set to a logic 0 when transmitted and interpreted by the Remote I/O as data bytes.
Bit 5: Not Used
Bit 6: IRQ Output Control
This bit controls the state of the Remote Bus IRQ line. When bit 6 is set to a logic 1, the
IRQ line of the Remote Bus is activated. When bit 6 is set to a logic 0, the IRQ line will
be put into receive mode.
Bit 7: DLAB Control
This bit is used to control access to the Baud Rate Select Register. If this bit is set to a
logic 0, the Receive buffer, Transmit buffer, and Interrupt Enable register may be
accessed. If this bit is set to a logic 1, only the Baud Rate Select register may be
accessed at offset 0.
Bit 3 Bit 0 Format
1 1 9 Data Bits, 1 Stop Bit *
0 1 8 Data Bits, 1 Stop Bit **
1 0 7 Data Bits, 1 Parity Bit, 1 Stop B
(Parity will always be even)
0 0 Reserved
* 9 Bit mode is used to communicate to Remote I/O using
binary protocol.
** 8 Bit mode is used to communicate to Remote I/O
using ASCIIprotocol.
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AC37 High-Speed Communication Adapter Card
MODEM CONTROL REGISTER: OFFSET 4 – READ/WRITE
Thisregister is associated with modems innameonly.The AC37 doesnotsupportmodemcontrol. This register has
beenprovided to support other features, in thiscase the secondary interrupt.The secondary interrupt featureon
AC37is used by theRemoteBusIRQline. Only one bit intheregisteris used for this purpose;otherbitsarenot used.
Thereare two basicversionsofthe AC37 in thefield:anolder full-length card andanewerhalf-size card. Thenewer
cardsupportstheuse of this bit to enable interrupts. TheolderAC37doesnot support the use of this bit; however,
werecommend that the bit still beset to ensure compatibility with allversions.
NOTE: Ifyou are using Windows NT, you mustuse the newer AC37,and its U5 must be labeled 9087.Earlier
versionswill not work with NT.
Bits 0–2: Not Used
Bit 3: Secondary Interrupt Enable
This bit is cleared upon power-up reset and must be set for the secondary interrupt to
be enabled.
Bits 4–7: Not Used
2-7
REGISTER DEFINITION
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