SeaLevel ULTRA 485 User manual

Sealevel Systems, Inc.
155 Technology Place
P.O. Box 830
Liberty, SC 29657 USA
Phone: [phone]
FAX: [phone]
www.sealevel.com
ULTRA 485
USER MANUAL
TM

Contents
INTRODUCTION ........................................................................ 1
OVERVIEW ...........................................................................................1
WHAT’S INCLUDED..............................................................................1
FACTORY DEFAULT SETTINGS..............................................................1
CARD SETUP............................................................................. 2
ADDRESS SELECTION............................................................................2
IRQ SELECTION...................................................................................3
INTERRUPT MODES ..............................................................................4
RS-485 ENABLE MODES.....................................................................5
CONNECTOR PIN ASSIGNMENTS...........................................................7
EIA-530..........................................................................................7
SIO-485..........................................................................................8
LINE TERMINATION..............................................................................9
INSTALLATION........................................................................ 10
OPERATING SYSTEM INSTALLATION ..................................................10
For Windows Users.....................................................................10
Other Operating Systems ............................................................10
TECHNICAL DESCRIPTION ..................................................... 11
FEATURES..........................................................................................11
SPECIFICATIONS..................................................................... 12
ENVIRONMENTAL SPECIFICATIONS.....................................................12
MANUFACTURING..............................................................................12
POWER CONSUMPTION......................................................................12
MEAN TIME BETWEEN FAILURES (MTBF)........................................12
PHYSICAL DIMENSIONS......................................................................12
APPENDIX A -TROUBLESHOOTING....................................... 13
APPENDIX B -HOW TO GET ASSISTANCE............................. 15
APPENDIX C -ELECTRICAL INTERFACE................................ 16
RS-530.............................................................................................16
RS-422.............................................................................................16
RS-485.............................................................................................17
APPENDIX D -ASYNCHRONOUS COMMUNICATIONS ............ 18
APPENDIX E -SILK-SCREEN.................................................. 19

APPENDIX F -COMPLIANCE NOTICES ................................... 20
FEDERAL COMMUNICATIONS COMMISSION STATEMENT...................20
EMC DIRECTIVE STATEMENT ...........................................................20
WARRANTY............................................................................ 21
Figures
Figure 1 -Header E1, IRQ Selection..............................................................3
Figure 2 -Header E2, Normal IRQ Mode ......................................................4
Figure 3 -Header E2, Shared IRQ Mode.......................................................4
Figure 4 -Header E5 RS-485 Transmit Mode................................................5
Figure 5 -Header E3 RS-485 Receive Mode.................................................6
Figure 6 -DIP-shunt E4 (EIA-530 Mode).......................................................7
Figure 7 -DIP-shunt E4 (SIO-485 Mode).......................................................8
Figure 8 -SW2, Line Termination...................................................................9
Figure 9 -Asynchronous Communications Bit Diagram...............................18
© 1999i Sealevel Systems, Incorporated. All rights reserved.

Introduction
Sealevel Systems ULTRA-485 Page 1
Introduction
Overview
The Sealevel Systems ULTRA 485 provides the PC with an additional
RS-422/485 serial port for terminals, PLC communication, laboratory
instrumentation, etc.
The unique feature of the ULTRA 485 is the ability to be RS-485 compatible
without the need for special software or drivers. This is especially useful in
Windows, Windows NT, and OS/2 environments where the lower level I/O
control is abstracted from the application program. Which means that the user
can effectively use the ULTRA 485 in an RS-485 application with existing (i.e.
standard RS-232) software drivers.
What’s Included
The ULTRA 485 is shipped with the following items. If any of these items are
missing or damaged, contact the supplier.
•ULTRA 485 Serial I/O Adapter
•Serial Utility Software
•User Manual
Factory Default Settings
The ULTRA 485 factory default settings are as follows:
Port # Base Address IRQ Electrical Specification
Port 1 280 5RS-485 ‘Auto’
To install the ULTRA 485 using factory default settings, refer to Installation on
page 10.
For your reference, record installed ULTRA 485 settings below:
Port # Base Address IRQ Electrical Specification

Card Setup
Sealevel Systems ULTRA-485 Page 2
Card Setup
The ULTRA 485 contains several jumper straps that must be set for proper
operation.
Address Selection
The ULTRA 485 occupies 8 consecutive I/O locations, and looks to the PC as a
standard serial port. A DIP-switch (SW1) is used to set the port address options
for the ULTRA 485. Be careful when selecting the port addresses as some
selections may conflict with existing ports. The following table shows the
addressing options available with the standard PAL. If different address options
are required, please contact Sealevel Systems Technical Support about a
custom PAL option.
Port1 J2 SW1-1SW1-2SW1-3SW1-4
Disabled On On On On
3F8 On On On Off
2F8 On On Off On
3E8 On On Off Off
2E8 On Off On On
3220 On Off On Off
3228 On Off Off On
4220 On Off Off Off
4228 Off On On On
238 Off On On Off
300 Off On Off On
308 Off On Off Off
280 Off Off On On
288 Off Off On Off
290 Off Off Off On
298 Off Off Off Off
Note: Each COM port in the system should have a unique address. Typically
COM1: -COM4: addresses are 3F8, 2F8, 3E8 & 2E8 Hex.

Card Setup
Sealevel Systems ULTRA-485 Page 3
IRQ Selection
Header E1 selects the interrupt request for each serial port. If COM1: is
selected, the corresponding jumper must be on the IRQ4 setting. If COM2: is
selected, the corresponding jumper must be on IRQ3.
Note: Most communications software applications default COM3: to IRQ4 and
COM4: to IRQ3. This requires the sharing of interrupts between COM1:
and COM3:, and between COM2: and COM4:. While this is the default,
it is not always the preferred setting. Check your software configuration
instructions to determine the most appropriate IRQ selection.
2 3 4 5 7 10 11 12 15
E1
Figure 1-Header E1, IRQ Selection
Any two or more ports can share a common IRQ by placing the jumpers on the
same IRQ setting at header E1 and setting the appropriate selections at E2.
Consult your particular software for IRQ selection. If no interrupt is desired,
remove the jumper.

Card Setup
Sealevel Systems ULTRA-485 Page 4
Interrupt Modes
Header E2 selects the interrupt mode for the ULTRA 485.
‘N’ indicates the (N)ormal, single interrupt per port mode. ‘S’ Indicates the
(S)hared interrupt mode, which allows more than one port to access a single
IRQ. Any two or more ports can share a common IRQ by placing the jumpers
on the same IRQ setting and setting the appropriate selections at E1. Consult
your particular software for IRQ selection. If no interrupt is desired, remove
the jumper. ‘M’ indicates the inclusion of a 1K ohm pull-down resistor
required on one port when sharing interrupts.
Figure 2-Header E2, Normal IRQ Mode
Set the jumper to ‘S’ if you are using more than one ULTRA 485 in a bus or to
completely remove the pull-down resistor for hardware compatibility. Setting
the adapter in this configuration when it is not accompanied by a pull-down
resistor will prevent the ports from triggering an interrupt.
Set the jumpers to ‘S’ for shared interrupt mode on all blocks sharing an IRQ
except one. Set that port block for ‘M’. This provides the pull-down resistor
circuit that makes sharing IRQs possible. If you are using more than one
ULTRA 485 or a compatible adapter in a bus you should only have one port set
to ‘M’. The following example shows two ULTRA 485 adapters sharing a single
IRQ.
Figure 3-Header E2, Shared IRQ Mode

Card Setup
Sealevel Systems ULTRA-485 Page 5
RS-485 Enable Modes
RS-485 is ideal for multi-drop or network environments. RS-485 requires a
tri-state driver (not dual-state) that will allow the electrical presence of the
driver to be removed from the line. The driver is in a tri-state or high
impedance condition when this occurs. Only one driver may be active at a time
and the other driver(s) must be tri-stated. The output modem control signal
Request To Send (RTS) is typically used to control the state of the driver.
Some communication software packages refer to RS-485 as RTS enable or
RTS block mode transfer.
One of the unique features of the ULTRA 485 is the ability to be RS-485
compatible without the need for special software or drivers. This ability is
especially useful in Windows, Windows NT, and OS/2 environments where the
lower level I/O control is abstracted from the application program. This ability
means that the user can effectively use the ULTRA 485 in a RS-485 application
with existing (i.e. standard RS-232) software drivers.
Header E5 is used to control the RS-485 mode functions for the transmitter
circuit. The selections are ‘RTS’ enable, ‘Auto’ enable, or ‘422’ which means
always enabled. The ‘Auto’ enable feature automatically enables/disables the
RS-485 transmitter circuit. The ‘RTS’ mode uses the ‘RTS’ modem control
signal to enable the RS-485 transmitter circuit and provides backward
compatibility with existing software products. The ‘422’ mode allows the port
to be used in a point to point RS-422 application where the tri-stating of the
transmitter circuit is not required.
AUTO Driver automatically enabled/disabled
RTS Driver enabled by UART RTS signal
422 Driver always enabled
Note: The jumper in the above example is in the ‘422’ position. This is the only
setting in which the modem control outputs (RTS, DTR) are valid.
Figure 4-Header E5 RS-485 Transmit Mode
RTS
422
AUTO
E5
TX

Card Setup
Sealevel Systems ULTRA-485 Page 6
Header E3 is used to control the RS-485 enable/disable functions for the
receiver circuit. The RS-485 ‘Echo’ is the result of connecting the receiver
inputs to the transmitter outputs. Every time a character is transmitted, it is also
received. This can be beneficial if the software can handle echoing (i.e. using
received characters to throttle the transmitter) or it can confuse the system if
the software does not. The selection at E3 should follow the selection made at
E5 if ‘No Echo’ is desired. If Echo suppression is not desired then leave the
jumper in the ‘422’ position. Also note, the modem control inputs (DSR, DCD,
CTS) are only valid when Header E3 is in the 422 mode. These header blocks
are described in the illustration and table that follow.
RTS
422
AUTO
E3
RX
AUTO Receiver automatically enabled/disabled
RTS Receiver enabled by UART RTS signal
422 Receiver always enabled
Figure 5-Header E3 RS-485 Receive Mode

Card Setup
Sealevel Systems ULTRA-485 Page 7
Connector Pin Assignments
EIA-530
DIP-shunt E4 selects the pin out for the DB-25 connector P3. With the 5
position shunt in the EIA-530 mode, the ULTRA 485 complies with the EIA-
530 pin out with the following signals supported:
EIA-530
E4
SIO-485
Figure 6-DIP-shunt E4 (EIA-530 Mode)
Signal Name Pin # Mode
GND Ground 7
RDB RX+ Receive Positive 16 Input
RDA RX-Receive Negative 3Input
CTSB CTS+ Clear To Send Positive 13 Input
CTSA CTS-Clear To Send Negative 5Input
DSRB DSR+ Data Set Ready Positive 22 Input
DSRADSR-Data Set Ready Negative 6Input
DCDB DCD+ Data Carrier Detect Positive 10 Input
DCDA DCD-Data Carrier Detect Negative 8Input
TDB TX+ Transmit Positive 14 Output
TDA TX-Transmit Negative 2Output
RTSB RTS+ Request To Send Positive 19 Output
RTSA RTS-Request To Send Negative 4Output
DTRB DTR+ Data Terminal. Ready Positive 23 Output
DTRA DTR-Data Terminal Ready Negative 20 Output

Card Setup
Sealevel Systems ULTRA-485 Page 8
SIO-485
With the 5-position shunt in the SIO-485 mode, the ULTRA 485 is compatible
with the Sealevel Systems SIO-485 (part# 3054) with the following signals
supported:
EIA-530
E4
SIO-485
Figure 7-DIP-shunt E4 (SIO-485 Mode)
/Signal Name Pin # Mode
GND Ground 7
TDB TX+ Transmit Positive 24 Output
TDA TX-Transmit Negative 25 Output
RDB RX+ Receive Positive 12 Input
RDA RX-Receive Negative 13 Input

Card Setup
Sealevel Systems ULTRA-485 Page 9
Line Termination
Typically, each end of the RS-485 bus must have line terminating resistors
(RS-422 terminates at the receive end only). A 100-ohm resistor is across each
RS-530/422/485 input in addition to a 1K ohm pull-up/pull-down combination
that biases the receiver inputs. DIP-switch SW2 provides the ability to
customize this interface to system requirements. Each switch position
corresponds to a specific portion of the interface. If multiple ULTRA 485
adapters are configured in a RS-485 network, only the boards on each end
should have switches T, P & P ON. Refer to the following table for each
position’s operation:
Name Function
TAdds or removes the 100 ohm termination.
PAdds or removes the 1K ohm pull-down resistor in the
RS-422/RS-485 receiver circuit (Receive data only).
PAdds or removes the 1K ohm pull-up resistor in the
RS-422/RS-485 receiver circuit (Receive data only).
LConnects the TX+ to RX+ for RS-485 two-wire operation.
LConnects the TX-to RX-for RS-485 two-wire operation.
Figure 8-SW2, Line Termination
1 2 3 4 5
ON
OFF
T P P L L

Installation
Sealevel Systems ULTRA-485 Page 10
Installation
Operating System Installation
For Windows Users
Start by choosing Install Software at the beginning of the CD. Choose
Asynchronous COM: Port Software, SeaCOM.
Other Operating Systems
Refer to the appropriate section of the Serial Utilities Software.System
Installation
The ULTRA 485 can be installed in any of the PC expansion slots. The ULTRA
485 contains several jumper straps for each port that must be set for proper
operation.
1. Turn off PC power. Disconnect the power cord.
2. Remove the PC case cover.
3. Locate an available slot and remove the blank metal slot cover.
4. Gently insert the ULTRA 485 into the slot. Make sure that the adapter is
seated properly.
5. Replace the screw.
6. Replace the cover.
7. Connect the power cord.
Installation is complete.

Technical Description
Sealevel Systems ULTRA-485 Page 11
Technical Description
The ULTRA 485 utilizes the 16550 UART. This chip features programmable
baud rates, data format, interrupt control and a 16-byte input and output FIFO. A
full array of advanced UARTS is also available.
The unique feature of the ULTRA 485 is the ability to be RS-485 compatible
without the need for special software or drivers. This is especially useful in
Windows, Windows NT, and OS/2 environments where the lower level I/O
control is abstracted from the application program. Which means that the user
can effectively use the ULTRA 485 in a RS-485 application with existing (i.e.
standard RS-232) software drivers.
Features
•Automatic RS-485 driver enable/disable allows card to appear to be
standard COM: port requiring no additional drivers
•‘PAL’ option allows for unique OEM address selection
•‘Shareable’ IRQs allow more than one port to share a single IRQ provided
a polling type driver is used
•IRQs 2/9-7, 10, 11, 12, 14, 15 supported
•16550 buffered UART standard
•16 Bit address decode allows for easier integration

Specifications
Sealevel Systems ULTRA-485 Page 12
Specifications
Environmental Specifications
Specification Operating Storage
Temperature Range 0º to 50º C
(32º to 122º F) -20º to 70º C (-4º to 158º F)
Humidity Range 10 to 90% R.H.
Non-Condensing 10 to 90% R.H. Non-Condensing
Manufacturing
•All Sealevel Systems Printed Circuit boards are built to U.L. 94V0 rating
and are 100% electrically tested. These printed circuit boards are solder
mask over bare copper or solder mask over tin nickel.
Power Consumption
Supply line +5 VDC
Rating 160 mA
Mean Time Between Failures (MTBF)
Greater than 150,000 hours. (Calculated)
Physical Dimensions
Board length 5.0 inches (12.70 cm)
Board Height including Goldfingers 4.2 inches (10.66 cm)
Board Height excluding Goldfingers
Board Weight 3.9 inches (9.91 cm) 0.22 Lbs.

Appendix A -Troubleshooting
Sealevel Systems ULTRA-485 Page 13
Appendix A -Troubleshooting
Serial Utility test software is supplied with the Sealevel Systems adapter and
will be used in the troubleshooting procedures. By using this software and
following these simple steps, most common problems can be eliminated
without the need to call Technical Support.
1. Identify all I/O adapters currently installed in your system. This includes
your on-board serial ports, controller cards, sound cards etc. The I/O
addresses used by these adapters, as well as the IRQ (if any) should be
identified.
2. Configure your Sealevel Systems adapter so that there is no conflict with
currently installed adapters. No two adapters can occupy the same I/O
address.
3. Make sure the Sealevel Systems adapter is using a unique IRQ. The IRQ is
typically selected via an on-board header block. Refer to the section on
Card Setup for help in choosing an I/O address and IRQ.
4. Make sure the Sealevel Systems adapter is securely installed in a
motherboard slot.
5. When running DOS, Windows 3.x or other operating systems refer to the
Serial Utilities software for that operating system and the User Manual to
verify that the Sealevel Systems adapter is configured correctly. The
supplied software contains a diagnostic program 'SSD' that runs under DOS
and will verify if an adapter is configured properly. This diagnostic
program is written with the user in mind and is easy to use. Refer to the
DIAG.txt file in the dos\diag directory for detailed instructions on using
'SSD'.
6. For Windows 95/98 and Windows NT, the diagnostic tool 'WinSSD' is
installed in the Sealevel folder on the Start Menu during the setup process.
First find the ports using the Device Manager, then use 'WinSSD' to verify
that the ports are functional.
7. Always use the Sealevel Systems diagnostic software when
troubleshooting a problem. This will help eliminate any software issues
and identify any hardware conflicts.

Appendix A -Troubleshooting
Sealevel Systems ULTRA-485 Page 14
8. The following are known I/O conflicts:
•The 278 and 378 settings may conflict with your printer I/O adapter.
•3B0 cannot be used if a Monochrome adapter is installed.
•3F8-3FF is typically reserved for COM1:
•2F8-2FF is typically reserved for COM2:
•3E8-3EF is typically reserved for COM3:
•2E8-2EF is typically reserved for COM4:

Appendix B -How To Get Assistance
Sealevel Systems ULTRA-485 Page 15
Appendix B -How To Get Assistance
Please refer to Appendix A -Troubleshooting prior to calling Technical
Support.
1. Read this manual thoroughly before attempting to install the
adapter in your system.
2. When calling for technical assistance, please have your user
manual and current adapter settings. If possible, please have the
adapter installed in a computer ready to run diagnostics.
3. Sealevel Systems maintains a Home page on the Internet. Our
home page address is www.sealevel.com. The latest software
updates, and newest manuals are available via our FTP site that can
be accessed from our home page.
4. Technical support is available Monday to Friday from 8:00 a.m. to
5:00 p.m. Eastern time. Technical support can be reached at (864)
843-4343.
RETURN AUTHORIZATION MUST BE OBTAINED FROM SEALEVEL
SYSTEMS BEFORE RETURNED MERCHANDISE WILL BE ACCEPTED.
AUTHORIZATION CAN BE OBTAINED BY CALLING SEALEVEL
SYSTEMS AND REQUESTING A RETURN MERCHANDISE
AUTHORIZATION (RMA) NUMBER.

Appendix C -Electrical Interface
Sealevel Systems ULTRA-485 Page 16
Appendix C -Electrical Interface
RS-530
RS-530 (a.k.a. EIA-530) compatibility means that RS-422 signal levels are
met, and the pin-out for the DB-25 connector is specified. The EIA (Electronic
Industry Association) created the RS-530 specification to detail the pin-out,
and define a full set of modem control signals that can be used for regulating
flow control and line status. The RS-530 specification defines two types of
interface circuits, Data Terminal Equipment (DTE) and Data Circuit-
Terminating Equipment (DCE). The Sealevel Systems adapter is a DTE
interface.
RS-422
The RS-422 specification defines the electrical characteristics of balanced
voltage digital interface circuits. RS-422 is a differential interface that defines
voltage levels and driver/receiver electrical specifications. On a differential
interface, logic levels are defined by the difference in voltage between a pair of
outputs or inputs. In contrast, a single ended interface, for example RS-232,
defines the logic levels as the difference in voltage between a single signal and
a common ground connection. Differential interfaces are typically more
immune to noise or voltage spikes that may occur on the communication lines.
Differential interfaces also have greater drive capabilities that allow for longer
cable lengths. RS-422 is rated up to 10 Megabits per second and can have
cabling 4000 feet long. RS-422 also defines driver and receiver electrical
characteristics that will allow 1 driver and up to 32 receivers on the line at
once. RS-422 signal levels range from 0 to +5 volts. RS-422 does not define a
physical connector.