SeaLevel ULTRA 485.PCI User manual

Part # 7105
Sealevel Systems, Inc
155 Technology Place
P.O. Box 830
Liberty, SC 29657 USA
Phone: [phone]
FAX: [phone]
www.sealevel.com
ULTRA 485.PCI
USER MANUAL
TM

Contents
INTRODUCTION........................................................................ 1
OVERVIEW......................................................................................1
WHAT’S INCLUDED.........................................................................1
FACTORY DEFAULT SETTINGS ........................................................1
CARD SETUP ............................................................................ 2
RS-485 ENABLE MODES.................................................................2
CLOCK MODES ...............................................................................3
BAUD RATES AND DIVISORS FOR THE ‘DIV1’ MODE .......................4
ADDRESS AND IRQ SELECTION.......................................................5
LINE TERMINATION ........................................................................5
INSTALLATION......................................................................... 6
OPERATING SYSTEM INSTALLATION ...............................................6
For Windows Users.....................................................................6
Other Operating Systems.............................................................6
SYSTEM INSTALLATION...................................................................6
TECHNICAL DESCRIPTION ...................................................... 7
CONNECTOR PIN ASSIGNMENTS......................................................7
RS-422/485/530 Pin Assignments (DB-25 Male DTE)..............7
SPECIFICATIONS...................................................................... 8
ENVIRONMENTAL SPECIFICATIONS .................................................8
MANUFACTURING...........................................................................8
POWER CONSUMPTION....................................................................8
MEAN TIME BETWEEN FAILURES (MTBF).....................................8
PHYSICAL DIMENSIONS...................................................................8
APPENDIX A -TROUBLESHOOTING ........................................ 9
APPENDIX B -HOW TO GET ASSISTANCE............................ 10
APPENDIX C -ELECTRICAL INTERFACE .............................. 11
RS-422.........................................................................................11
RS-485.........................................................................................11
RS-530.........................................................................................12
APPENDIX D -ASYNCHRONOUS COMMUNICATIONS............ 13
APPENDIX E -SILK-SCREEN................................................. 14

APPENDIX F -COMPLIANCE NOTICES.................................. 15
FEDERAL COMMUNICATIONS COMMISSION STATEMENT...............15
EMC DIRECTIVE STATEMENT ......................................................15
WARRANTY............................................................................ 16
Figures
Figure 1-Switch SW2, RS-422..................................................................3
Figure 2 –Switch SW2, RS-485 ‘Auto’ Enabled, with ‘No Echo’..........3
Figure 3 -Switch SW2, RS-485 ‘Auto’ Enabled, with ‘Echo’................3
Figure 4 -Switch SW1, Line Termination ...............................................5
Figure 5 -Asynchronous Communications Bit Diagram......................13
© 2001e Sealevel Systems, Incorporated. All rights reserved.

Introduction
Sealevel Systems ULTRA 485.PCI Page 1
Introduction
Overview
The Sealevel Systems ULTRA 485.PCI is a one channel PCI Bus serial I/O
adapter. It provides one field selectable RS-422/485/530 serial port supporting
asynchronous data rates up to 460.8K bps.
Choose the RS-422 mode for long distance device connections up to 4000ft.
where noise immunity and high data integrity are essential. Select RS-485 and
capture data from multiple peripherals in a RS-485 multi-drop network. Up to 31
RS-485 devices can be connected to each port to automate your data collection.
In RS-485 mode, our special auto-enable feature allows the RS-485 ports to be
viewed by the operating system as a COM: port. This allows the standard COM:
driver to be utilized for RS-485 communications. Our on-board hardware
automatically handles the RS-485 driver enable.
What’s Included
The ULTRA 485.PCI is shipped with the following items. If any of these items
is missing or damaged, contact the supplier.
??ULTRA 485.PCI Serial I/O Adapter
??Sealevel Software
Factory Default Settings
The ULTRA 485.PCI factory default settings are as follows:
Port # Electrical Specification
Port 1 RS-530

Card Setup
Sealevel Systems ULTRA 485.PCI Page 2
Card Setup
RS-485 Enable Modes
RS-485 is ideal for multi-drop or network environments. RS-485 requires a
tri-state driver 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.PCI is the ability to be RS-485
compatible without the need for special software or drivers. This ability is
especially useful in Windows 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.PCI in an RS-485 application with
existing (i.e. standard RS-232) software drivers.
Switch SW2 is used to control the RS-485 mode functions for the driver circuit.
The selections are:
‘Auto’ enable (silk-screen ‘AT’). The ‘Auto’ enable feature automatically
enables/disables the RS-485 interface via on board circuitry.
‘RTS’ enable (silk-screen ‘RT’) The ‘RTS’ mode uses the ‘RTS’ modem control
signal to enable the RS-485 interface and provides backward compatibility with
existing software products.
‘No Echo’ (silk-screen ‘NE’) is used to control the RS-485 enable/disable
functions for the receiver circuit and determine the state of the RS-422/485
driver. 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. To select the ‘No Echo’ mode select silk-screen position ‘NE’.

Card Setup
Sealevel Systems ULTRA 485.PCI Page 3
Clock Modes
The ULTRA 485.PCI employs a unique clocking option that allows the end user
to select from divide by 4 and divide by 1 clocking modes. SW2 positions 1 and
2 select the Divide by 1 (silk-screen D1) and Divide by 4 (silk-screen D4)
modes.
To select the Baud rates commonly associated with COM: ports (i.e. 2400,
4800, 9600, 19.2, … 115.2K Bps ) set switch SW2 in the divide by 4 mode (silk-
screen D4).
To select the maximum data rate up to 460.8K bps set switch SW2 in the divide
by 1 (silk-screen D1) position. Please refer to the following page for these
additional data rates.
Caution: Do not set both switches on or invalid clocking will occur.
RS-485 Mode and Clock Mode Examples (Switch SW2)
Figure 1-Switch SW2, RS-422, Divide by 4
Figure 2 –Switch SW2, RS-485 ‘Auto’ Enabled, with ‘No Echo’ Divide by 4
Figure 3 -Switch SW2, RS-485 ‘Auto’ Enabled, with ‘Echo’ Divide by 4
1 2 3 4
ON
OFF 5
D
1D 4A TR TN E
1 2 3 4
ON
OFF 5
D
1D 4A TR TN E
1 2 3 4
ON
OFF 5
D
1D 4A TR TN E

Card Setup
Sealevel Systems ULTRA 485.PCI Page 4
Baud Rates and Divisors for the ‘Div1’ mode
The following table shows some common data rates and the rates you should
choose to match them if using the adapter in the ‘Div1’ mode.
For this Data Rate Choose this Data Rate
1200 bps 300 bps
2400 bps 600 bps
4800 bps 1200 bps
9600 bps 2400 bps
19.2K bps 4800 bps
57.6 K bps 14.4K bps
115.2 K bps 28.8K bps
230.4K bps 57.6 K bps
460.8K bps 115.2 K bps
If your communications package allows the use of Baud rate divisors, choose the
appropriate divisor from the following table:
For this Data Rate Choose this Divisor
1200 bps 384
2400 bps 192
4800 bps 96
9600 bps 48
19.2K bps 24
38.4K bps 12
57.6K bps 8
115.2K bps 4
230.4K bps 2
460.8K bps 1

Card Setup
Sealevel Systems ULTRA 485.PCI Page 5
Address and IRQ selection
The ULTRA 485.PCI is automatically assigned resources by your motherboard
BIOS. Only the I/O address may be modified by the user.
Adding or removing other hardware may change the assignment of I/O addresses
and IRQs.
Line Termination
Typically, each end of the RS-485 bus must have line-terminating resistors
(RS-422 terminates at the receive end only). A 120-ohm resistor is across each
RS-422/485 input in addition to a 1K-ohm pull-up/pull-down combination that
biases the receiver inputs. Switch SW1 allows customization of this interface to
specific requirements. Each switch position corresponds to a specific portion of
the interface. If multiple ULTRA 485.PCI adapters are configured in an 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 120 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 4 -Switch SW1, Line Termination
1 2 3 4
ON
OFF 5
P P T L L

Installation
Sealevel Systems ULTRA 485.PCI Page 6
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
System Installation
The ULTRA 485.PCI can be installed in any of the PCI expansion slots and
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 PCI slot and remove the blank metal slot cover.
4. Gently insert the ULTRA 485.PCI 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.PCI Page 7
Technical Description
The Sealevel Systems ULTRA 485.PCI provides an additional asynchronous
serial port, field selectable as RS-422/485/530 for industrial automation and
control applications.
The ULTRA 485.PCI utilizes the EXAR 16C850 UART. This chip features
programmable baud rates, data format, interrupt control and an industry leading
128 byte FIFOs.
Connector Pin Assignments
RS-422/485/530 Pin Assignments (DB-25 Male DTE)
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
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
Note: These assignments meet the EIA/TIA/ANSI-530 DTE.