SeaLevel C4-104 Series User manual

1
© Sealevel Systems, Inc. 3520, 3521, 3522 Manual | SL9054 12/2022
C4-104
User Manual | 3520, 3521, 3522

2
© Sealevel Systems, Inc. 3520, 3521, 3522 Manual | SL9054 12/2022
Contents
CONTENTS...........................................................................................................................................................2
INTRODUCTION ................................................................................................................................................... 3
BEFORE YOU GET STARTED ...............................................................................................................................4
CARD SETUP ........................................................................................................................................................5
SOFTWARE INSTALLATION ................................................................................................................................9
PHYSICAL INSTALLATION................................................................................................................................11
TECHNICAL DESCRIPTION ...............................................................................................................................12
SPECIFICATIONS ...............................................................................................................................................14
APPENDIX A – TROUBLESHOOTING................................................................................................................15
APPENDIX B – HOW TO GET ASSISTANCE .....................................................................................................16
APPENDIX C – ELECTRICAL INTERFACE ........................................................................................................17
APPENDIX D – PC/104......................................................................................................................................19
APPENDIX E – SILK SCREEN ............................................................................................................................20
APPENDIX F – COMPLIANCE NOTICES...........................................................................................................21
WARRANTY ........................................................................................................................................................22

3
© Sealevel Systems, Inc. 3520, 3521, 3522 Manual | SL9054 12/2022
Introduction
Overview
The Sealevel Systems C4-104 series provides four selectable RS-232 or RS-422/485 serial I/O ports for
your PC/104 application.
Factory Default Settings
The C4-104 factory default settings are as follows:
Base Address
IRQ
Port 1
280
5
Port 2
288
5
Port 3
290
5
Port 4
298
5
For your reference, record installed C4-104 settings below:
Base Address
IRQ
Port 1
Port 2
Port 3
Port 4

4
© Sealevel Systems, Inc. 3520, 3521, 3522 Manual | SL9054 12/2022
Before You Get Started
What’s Included
The C4-104 is shipped with the following items. If any of these items are missing or damaged, contact the
supplier.
• (1) C4-104 Serial Interface Adapter
• (4) DB-9 Cable Assemblies
• (1) Nylon Hardware Kit
Advisory Conventions
Warning
The highest level of importance used to stress a condition where damage could result to the
product, or the user could suffer serious injury.
Important
The middle level of importance used to highlight information that might not seem obvious or a
situation that could cause the product to fail.
Note
The lowest level of importance used to provide background information, additional tips, or other
non-critical facts that will not affect the use of the product.

5
© Sealevel Systems, Inc. 3520, 3521, 3522 Manual | SL9054 12/2022
Card Setup
The C4-104 contains several jumper straps for each port that must be set for proper operation.
Address Selection
The C4-104 occupies four port addresses with each port occupying 8 consecutive I/O locations. A DIP
switch (SW1) is used to set the port address options for the C4-104. 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 you do not see an address option that suits your needs, please
contact Sealevel Systems Technical Support about a custom PAL option.
Port1
J1
Port2
J2
Port3
J3
Port4
J4
SW1
1
SW1
2
SW1
3
SW1
4
3F8
2F8
3E8
2E8
On
On
On
On
2F8
3E8
2E8
2E0
On
On
On
Off
3E8
2E8
280
288
On
On
Off
On
280
288
290
298
On
On
Off
Off
2A0
2A8
2B0
2B8
On
Off
On
On
500
508
510
518
On
Off
On
Off
580
588
590
598
On
Off
Off
On
Figure 1 - Address Selection Table
DOS Note
Typically COM1: through COM4: addresses are 3F8, 2F8, 3E8 & 2E8 Hex (this is the first
addressing option in the above table). If a COM1: is already present use the second addressing
option, this will provide the typical addresses for COM2: through COM4: and a fourth port address
at 2E0 Hex.
Port #
Connector Location
1
J2
2
J3
3
J4
4
J5
Figure 2 - Port to Connector Table

6
© Sealevel Systems, Inc. 3520, 3521, 3522 Manual | SL9054 12/2022
IRQ Selection
Headers E1-E4 select the Interrupt Request (IRQ) for each serial port. E1 selects the IRQ selection for Port
1, E2 for Port 2, E3 for Port 3, and E4 for Port 4. If COM1: is selected, this jumper must be on the IRQ4
setting. If COM2: is selected, this jumper must be on IRQ3. Consult your particular software for IRQ
selection. If no interrupt is desired, remove the jumper.
E1 E2 E3 E4
2/9
3
4 5
7
10 11
12
15
R
Figure 3 – Headers E1, E2, E3, & E4 – IRQ Selection
Position “R” is provided so that you can install a jumper that connects a 1K ohm pull-down resistor to the
output of a high-impedance tri-state driver that carries the IRQ signal. Because the IRQ line is driven low
only by the pull-down resistor you can have two or more boards which share the same IRQ signal. Position
“R” installed is the default setting and should be left on unless multiple ports or cards are sharing a single
IRQ. If multiple ports or cards are sharing a single IRQ then only one pull-down resistor is needed in the
circuit.
RS-485 Mode (RTS Enable)
E7 & E8 select whether the RS-485 driver is enabled by the UART signal Request To Send (RTS) or always
enabled. With the jumper installed, RTS enables the RS-485 driver. Removing the jumper enables the driver
regardless of RTS. The jumper should be installed for a 2/4 wire RS-485 application where the C4-104 is
acting as a polled node on a multi-drop network. Remove the jumper if you are using a point to point RS-
422 application such as Programmable Logic Controllers (PLC's), etc. Half-duplex two-wire operation is
also possible by connecting TX+ to RX+ and TX- to RX- in your cable hood.
To enable the driver with RTS install jumpers at E7-1 for Port 1, E7-3 for Port 2, E8-1 for Port 3, and E8-3 for
Port 4. Failure to correctly set this jumper can cause transmitter contention problems preventing operation
by any nodes on the network.

7
© Sealevel Systems, Inc. 3520, 3521, 3522 Manual | SL9054 12/2022
By connecting the TX+ to the RX+ and TX- to RX- you will experience a condition termed RS-485 “Echo”. This
means that when you transmit a data character it will be “Echoed” back through the receiver circuit, presenting
itself as a received data character. This can be useful in RS-485 communications by providing a benchmark for
the end of transmission (i.e., when the amount of received data available equals the transmit data count). The
RS-485 “Echo” can be disabled at E7 and E8. To disable the echo install a jumper at E7-2 for Port 1, E7-4 for
Port 2, E8-2 for Port 3, and E8-4 for Port 4.
The following example shows the drivers in the RS-485 mode and the echo enabled.
1 2 3 4
E7-1
Port 1 RS-485 Enable
E7-2
Port 1 RS-485 Echo Disable
E7-3
Port 2 RS-485 Enable
E7-4
Port 2 RS-485 Echo Disable
E8-1
Port 3 RS-485 Enable
E8-2
Port 3 RS-485 Echo Disable
E8-3
Port 4 RS-485 Enable
E8-4
Port 4 RS-485 Echo Disable
Figure 4 - Headers E7 and E8 - RS-485 Enable and Echo Selection
Interface Selection
Due to the versatility of the C4-104, a wide range of interface configuration options is available to the end
user. Please use this section as a guide in configuring your board to provide the interface you require.
RS-232
1. Remove the 75174 drivers at U1 & U5.
2. Install MAX204 drivers at U2 & U6.
3. Remove all jumpers at E5 and E6.
RS-422/485
1. Install the 75174 drivers at U1 & U5.
2. Remove MAX204 drivers at U2 & U6.
3. Install all jumpers at E5 and E6.

8
© Sealevel Systems, Inc. 3520, 3521, 3522 Manual | SL9054 12/2022
Combined RS-232 & RS-422/485
Please use the following table as a guide in configuring the C4-104 in this manner.
Configuration Drivers Headers E5 and E6
Ports 1 & 2 RS-232
Ports 3 & 4 RS-422
U2 & U5 Installed
U1 & U6 Removed
E6 jumpers Removed
E5 jumpers Installed
Ports 1 & 2 RS-422
Ports 3 & 4 RS-232
U1 & U6 Installed
U2 & U5 Removed
E6 jumpers Installed
E5 jumpers Removed

9
© Sealevel Systems, Inc. 3520, 3521, 3522 Manual | SL9054 12/2022
Software Installation
Windows Installation
Do not install the Adapter in the machine until the software has been fully installed.
Only users running Windows 7 or newer should utilize these instructions for accessing and
installing the appropriate driver via Sealevel’s website. If you are utilizing an operating system
prior to Windows 7, please contact Sealevel by calling 864.843.4343 or emailing
[email protected] to receive access to the proper driver download and installation
instructions.
1. Begin by locating, selecting, and installing the SeaCOM Asynchronous Serial Software
Suite.
2. Select “Download Now” for SeaCOM for Windows.
3. The setup files will automatically detect the operating environment and install the proper
components. Follow the information presented on the screens that follow.
4. A screen may appear with text similar to: “The publisher cannot be determined due to the
problems below: Authenticode signature not found.” Please click the ‘Yes’ button and
proceed with the installation. This declaration simply means that the operating system is
not aware of the driver being loaded. It will not cause any harm to your system.
5. During setup, the user may specify installation directories and other preferred
configurations. This program also adds entries to the system registry that are necessary
for specifying the operating parameters for each driver. An uninstall option is also included
to remove all registry/INI file entries from the system.
6. The software is now installed, and you can proceed with the hardware installation.
Linux
Refer to the Linux.serial.readme file found in the Sealevel Systems Linux SeaCOM software. This file
contains valuable information on installing your adapter in the various Linux releases. Also in this sub-
directory is the Linux SerialHOWTO. This series of files explains typical Linux serial implementations, as
well as informing the user to Linux syntax and preferred practices.

10
© Sealevel Systems, Inc. 3520, 3521, 3522 Manual | SL9054 12/2022
QNX
Refer to the QNX6\Install.readme file in Sealevel System’s SeaCOM software. This file contains valuable
information on installing your adapter in the QNX6 Neutrino OS, as well as the files required to ensure a
flawless implementation. Also provided are implementation instructions for QNX4. These are found in in
a file called - QNX4\QNX_COM.txt.
For additional software support, please call Sealevel Systems’ Technical Support, [phone]. Our
technical support is free and available from 8:00 AM - 5:00 PM Eastern Time, Monday through Friday. For
email support contact: [e-mail].