SeaLevel LATCH-16 User manual

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© Sealevel Systems, Inc. 3097 Manual | SL9124 12/2022
LATCH-16
PART #3097
USER MANUAL
LATCH-16
User Manual | 3097

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© Sealevel Systems, Inc. 3097 Manual | SL9124 12/2022
Contents
CONTENTS...........................................................................................................................................................2
INTRODUCTION ................................................................................................................................................... 3
BEFORE YOU GET STARTED ...............................................................................................................................4
INSTALLATION ....................................................................................................................................................5
CARD SETUP ........................................................................................................................................................5
PORT ENABLE / DISABLE....................................................................................................................................6
TECHNICAL DESCRIPTION ................................................................................................................................. 6
SOFTWARE INSTALLATION................................................................................................................................8
SPECIFICATIONS ...............................................................................................................................................10
APPENDIX A – TROUBLESHOOTING................................................................................................................11
APPENDIX B – HOW TO GET ASSISTANCE .....................................................................................................12
APPENDIX C – COMPLIANCE NOTICES ..........................................................................................................13
WARRANTY ........................................................................................................................................................14

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© Sealevel Systems, Inc. 3097 Manual | SL9124 12/2022
Introduction
Latching relays retain their state until they are changed by the user. Power conditions do not affect the
latching relays; therefore, the PC can be powered up or down without altering the state of the latch. Latching
Relays have two coils as compared to normal relays , with one coil. The two coils are labeled "set” and
“reset”. When either “set” or “reset” coil is energized, the relay switches to that state and remains there until
the opposite coil is pulsed. This allows “non-volatility” in the relay circuit. The Sealevel LATCH-16 provides
two 8-bit latching relay output ports. This allows the user to set the LATCH-16 to a desired state, which is
unaffected by power loss or interruption. The 16 relays remain in the desired state regardless of the power
up / down condition of the PC. Software examples are included to help minimize development time.

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© Sealevel Systems, Inc. 3097 Manual | SL9124 12/2022
Before You Get Started
What’s Included
The LATCH-16 (3097) is shipped with the following items. If any of these items are missing or damaged,
please contact Sealevel for replacement.
•LATCH-16 (3097) Adapter
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.

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© Sealevel Systems, Inc. 3097 Manual | SL9124 12/2022
Installation
Be sure to set the Address and Jumper Options before installation.
The LATCH-16 can be installed in any of the PC expansion slots, except J8 on the original IBM "XT" and
Portable. Remove the PC case, remove the blank metal slot cover, and insert the board. Replace the
screw, replace the case, and the installation is complete.
Card Setup
Address Selection
The LATCH-16 relay output board occupies a total of four consecutive I/O locations. A dip switch is used
to set the base address for these locations. Be careful when selecting the base address as some selections
conflict with existing PC ports. The following table shows several examples that usually do not cause a
conflict.
The address line A9 is always “1”.
Address
Binary
Switch Setting
Hex
A9
A8 A0
1
2
3
4
5
6
7
300-303
1
1000000XX
Off
Cn
On
On
On
On
On
304-307
1
1000001XX
Off
Cn
On
On
On
On
Off
310-313
1
1000100XX
Off
On
On
On
Off
On
On
314-317
1
1000101XX
Off
On
On
On
Off
On
Off
320-323
1
1001000XX
Off
On
On
On
Off
On
On
3A0-3A3
1
1101000XX
Off
Off
On
Off
On
On
On
Figure 1 - Address Selection Table

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© Sealevel Systems, Inc. 3097 Manual | SL9124 12/2022
The following table shows the correlation between the dip switch setting and the address bits used to
determine the base address. Assume 300 Hex to 303 Hex is the desired base address. 300 Hex=11 0000
0X in Binary.
Switch Position
Address Line
Binary
Switch Setting
N/A
A9
1
Always a 1
1
A8
1
OFF
2
A7
0
ON
3
A6
0
ON
4
A5
0
ON
5
A4
0
ON
6
A3
0
ON
7
A2
0
ON
Figure 2 - Addressing Example
Setting the switch “On” or “Closed” corresponds to a “0” in the address, while leaving it “Off” or “Open”
corresponds to a “1”.
Port Enable / Disable
The LATCH-16 can be enabled or disabled with switch position 8 on the dipswitch. The port is enabled with
the switch "On" or "Closed" and disabled when "Off" or "Open".
Technical Description
The LATCH-16 provides two eight bit latched relay output ports. Latched Relays maintain their set or reset
condition until set or reset again, regardless of power conditions. This allows the user to set the LATCH-16
relays in a required state and power down the computer. When a change is required, the user can simply
set or reset the relay(s) again.
The terms “set” and “reset” are used to define the state of the relay. Set means that the relay “S” coil
has been energized, and the relay contacts are closed. Reset means that the relay “R” coil has been
energized, and the contacts are open.
The Latch-16 is easily programmed as simple Port I/0. To set a relay, the corresponding bit in Base+0 (or
Base+2) must be written as a “0”. To reset a relay, the corresponding bit in Base+1 (or Base+3) must be
written as a “0”. Writing to any of these registers causes a 6 mS. (Millisecond) pulse generator to energize
the relay coil. This particular hardware approach was chosen to keep the controlling software from having
to use timing routines and perform tedious I/O operations.

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© Sealevel Systems, Inc. 3097 Manual | SL9124 12/2022
While setting or resetting individual bits requires only one I/O write, writing a byte of data to the port
requires writing both the set and reset register. This is because only the “0” bits in the byte cause a set
or reset operation. Therefore, to write a byte (55 Hex) to Port A, first write a 55H to Base+0 and write the
complement (AA Hex) to Base+1.
Again, writing to these registers causes a 6 millisecond (mS) pulse to be applied to the relay coil. You must
avoid successive writes as this 6 mS pulse is necessary to energize the relay. By reading the registers at
Base+1 and Base+3 you can determine if a write is in process and wait until it is finished before initiating
another cycle. The status of the relays may be read back from Base+0 (K9-16) and Base+2 (K1-K8). Please
note that when reading the status of the relays, a set bit (1) corresponds to an Open relay and a clear bit
(0) corresponds to a Closed relay.
Read Operations
Base+0 An I/O read to Base+0 will return the status of the relays K9-K16. Reading a zero (0) indicates that
the relay is closed. (Port A see Figure 3 for actual Relay / Port-bit locations)
Base+1 An I/O read to Base+1 will return a 0 in bit position D0 if a write to Base+0 is in progress (Set A).
An I/O read to Base+1 will return a 0 in bit position D1 if a write to Base+1 is in progress (Reset A).
Base+2 An I/O read to Base+2 will return the status of the relays K1-K8 . Reading a zero (0) indicates that
the relay is closed. (Port B see Figure 3 for actual Relay / Port-bit locations)
Base+3 An I/O read to Base+3 will return a 0 in bit position D0 if a write to Base+2 is in progress (Set B).
An I/O read to Base+3 will return a 0 in bit position D1 if a write to Base+3 is in progress (Reset B).
Output Functions: Input Functions:
Base+0
Set relays on Port A (Relays K9-K16) Read status of relays K9-K16.
Base+1
Reset relays on Port A (Relays K9-K16) Read status of pulse generator (Port A).
Base+2
Set relays on Port B (Relays K1-K8) Read status of relays K1-K8.
Base+3
Reset relays on Port B (Relays K1-K8) Read status of pulse generator (Port B).

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© Sealevel Systems, Inc. 3097 Manual | SL9124 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 legacy driver download and installation instructions.
1. Begin by locating, selecting, and installing the correct software – SeaIO Classic Digital I/O Drivers.
Select ‘Download Now’ for the SeaIO Classic for Windows. In the Downloads section: select “SeaIO
Classic for Windows.” The setup file will automatically detect the operating environment and install
the proper components. Next (depending on your browser) select the ‘Run this program from its
current location’ or ‘Open’ option. Follow the information presented on the screens that follow.
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 available to remove SeaIO files and
registry/INI file entries from the system.
2. If installing in NT, skip to step 11. ‘Windows NT Card Installation.’
3. Go to the “Add New Hardware Wizard” in the Control Panel.
4. When the Wizard asks if you want Windows to search for the new hardware, choose “No, I want to
select the hardware from a list.”
5. Scroll through the list of categorized hardware and select ‘SeaIO Devices.’ If this is the first SeaIO
device you may need to select ‘Other Devices’ and ‘Sealevel Systems, Inc.’ instead of ‘SeaIO
Devices.’
6. Click “Next.”
7. Select the card model and press “Next.”
8. The Wizard will guide you through a few more informational prompts; continue to click “Next” until
it is completed.
9. Your card’s resource assignments may be adjusted through the Device Manager (if, for instance,
you need to change the I/O port address Windows assigned when you installed the card).
10. Windows software installation is complete
11. Windows NT Card Installation: After accomplishing steps 1 – 6, bring up the Control Panel and
double-click on the SeaIO Devices icon. To install a new card, click “Add Port.” Repeat this
procedure for as many SeaIO cards as you wish to install.

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© Sealevel Systems, Inc. 3097 Manual | SL9124 12/2022
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].
Port A
D0
K13
2,20
D1
K14
3,21
D2
K15
4,22
D3
K16
5,23
D4
K9
6,24
D5
K10
7,25
D6
K11
8,26
D7
K12
9,27
Port B
D0
K5
10,28
D1
K6
11,29
D2
K7
12,30
D3
K8
13,31
D4
K1
14,32
D5
K2
15,33
D6
K3
16,34
D7
K4
17,35
Power and Ground
Locations
Ground
18,36,37
+ 5 Volts
19
+ 12 Volts
1
Figure 3 Bit, Relay and Connector Pin Positions

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© Sealevel Systems, Inc. 3097 Manual | SL9124 12/2022
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
Performance
MTBF > 150,000 Hours
MTTR < .25 Hours
Turnaround For Repair 5 Working Days
Manufacturing
• IPC 610-A Class-III Standards adhered to with a 0.1 visual A.Q.L. and 100% Functional Testing.
• Boards are built to UL 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 210 mA