FAQ

Weather forecast communication
How are weather forecasts communicated to Seaware onboard software?
What email server protocols are supported in the online mode?

GPS connection
What should we think about when connecting a GPS?
How to find cabling and/or connectors in order to connect a GPS to a PC?
How do we manufacture a GPS-PC cable ourselves?
What to do when there are no free RS-232 ports (COM ports) available on the PC?
What to do when the GPS only outputs data using RS-422 (instead of the PC standard, RS-232)?
There is a GPS connected to the PC but another application is using the GPS data. Is this possible to resolve?
What to do when the connected GPS is sending at a different baud rate from 4800 bps?

How are weather forecasts communicated to Seaware onboard software?
All our onboard products use email-based communication. This means that requests from the ship for weather forecasts, as well as the forecast data returned, are sent as email attachments.

What email server protocols are supported in the online mode?
The email client that is embedded in all our onboard products support SMTP (outgoing) and POP3 (incoming) protocols. Alternatively, MAPI can be used, whick uses a locally installed email client such as Outlook or Windows Mail to acquire weather forecasts.

What should we think about when connecting a GPS?
GPS applications available on the market today (digital charts applications, chart plotters etc). Unfortunately the technology involved in GPS communication is old-fashioned and in some perspectives cumbersome. This is primarily due to two reasons:

1) The digital output from a GPS still relies on serial communication between one sender and one listener (usually referred to as RS-232 serial communication), i.e. there is no built-in support for networking a GPS.

2) The information sent by a GPS still relies on the NMEA protocol which has not been updated since decades, i.e. GPS manufacturers have become forced to deliver products using standards of their own, thus one may well encounter problems when connecting a GPS to any PC application, why this topic is all about understanding and assisting in overcoming such problems. These guidelines are presented as frequently-asked-questions below.Further, it is important to know that Seaware Routing and Seaware EnRoute do not require a GPS connection. Indeed it adds features, but is still optional.

How to find cabling and/or connectors in order to connect a GPS to a PC?
The general answer is that every GPS manufacturer normally offers prefabricated cables of their own to use. Onboard large vessels, however, such prefabricated cables may not be appropriate to use due to obstacles in the way of laying the cable, or the simple fact the prefabricated cable is too short. In such case it may be required to manufacture a custom cable (see next question).

How do we manufacture a GPS-PC cable ourselves?
The following picture shows an overview of the task. The material required is:

9-pin female D-sub connector (international standard).
Shielded signal cable of at least 2 wires.<//li>
A connector to the GPS which has been designated by the specific GPS manufacturer or dealer.

The cable wiring scheme is:

*As both the logical and physical interface to the GPS is dependant of the specific GPS used, neither the signal name nor the pin assignment may be defined within this scope.

What to do when there are no free RS-232 ports (COM ports) available on the PC?
This must be solved by inserting a PCI expansion board into the PC. There are USB-serial port adapters on the market claiming to do the job, but due to several trouble reports from users, Seaware does not recommend those. They cannot harm the PC or the software, but one should be observant of computer misbehavior upon trying this solution (such as extremely slow execution of programs using the USB adapter).

What to do when the GPS only outputs data using RS-422 (instead of the PC standard, RS-232)?
This must be solved by using a signal converter or a PCI expansion board that handles the conversion from RS-422 to RS-232. All - to Seaware known - GPS receivers on the market do have at least one RS-232 output, but naturally it may be occupied by some other listening device. In such case it is possible to purchase a RS-232 splitter in order to split the signal from the GPS to several listening devices. It is important to understand that such splitters include an amplifier to maintain the signal strength to all listening devices, i.e. it is not recommended to simply split the wires without an amplifier.

There is a GPS connected to the PC but another application is using the GPS data. Is this possible to resolve?
This is a limitation in MS Windows in that only one application at a time is allowed to access a serial port. There are vendors of supplementary software to get around this, such as Serial Port Splitter.

What to do when the connected GPS is sending at a different baud rate from 4800 bps?
As mentioned in the introduction, the NMEA standard is old-fashioned and still designates a transmission rate (baud rate) of 4800 [bits per second]. Most modern GPS receivers offer a lot more information (per second) to be sent than possible at that rate, why some manufacturers have decided to deviate from the NMEA standard.
If the connected GPS requires a baud rate different from 4800, this is currently not possible to change within the Seaware application as a user, but contact our support to resolve the problem.

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