How to read/write Route information to/from a GPS unit?

Question

Hi I am building a new application (Forms) to display GPS information etc on a laptop. I have been able to parse teh NMEA stntances and grab the information I need BUT now I need to download/upload the route information to/from the GPS unit. I have been unsuccessful so far in finding any code examples etc to help me. Can anyone steem me to something? Using VS2008 C# .NET 3.5 Visio. Thanks Phill

Phillip Seaman · Answer

Hi Sam Thanks for you insightful response. As I noted above I am in the process or completing a new Marine product to assist boaters in maintaining a log of there trips. I am currently testing against a Garmin GPS (several models) using a Serial port cable with adaptor and drivers. I am reading the NMEA (National Marine Electronics Association) standard sentances with no real problem. I found out late last night that one of the sentances send the Route/Trip information it was very burried so I think I just have to do a bit more reading and then code for the new sentance. If anyone is interested let me know and I'll put together some sort of post here... For now I have beta versions available for FREE download on the Downloads page of http://www.SeamanMarineSoftware.com Thanks SquireDude

Sam Hobbs · Answer

Gotta read the documentation of the GPS. You will nearly certainly not find samples anywhere if the vendor of the hardware does not provide any. You won't be able to communicate with the device without device drivers. Now I might be wrong but no one can help you without knowing at least what the device is. What type of interface is it? USB Bluetoth or something else?

Sam Hobbs · Answer

I don't know if the problem that theLizard encountered is because Microsoft has dropped 64-bit support of some database providers but it might be. If that is the problem then one solution is to set configuration of your project so that it is 32-bit (x86) only. I think that Microsoft has given in to pressure and is now offering 64-bit support of the databases they had intended to not support but I don't know the details and for a project such as yours that is under development I think it is good enough to just support 32-bit.

theLizard · Answer

I am not 100% sure but the error occurs at this point private void MDI_Main_Activated_1(object sender EventArgs e) { this.GetMDIVesselNameID(); this.ucVessel1.ChangeVessel = true; } public DataTable QueryDataGet(string pSQLText) { ErrorLogClass class2; DataTable table2; try { OleDbDataAdapter adapter = new OleDbDataAdapter(pSQLText this.CreateConnection()); OleDbCommandBuilder builder = new OleDbCommandBuilder(adapter); DataTable dataTable = new DataTable(); adapter.Fill(dataTable); class2 = new ErrorLogClass(); class2.LogCode = 0; class2.LogModule = Query Data Get; class2.LogMessage = Success Records returned. (  + dataTable.Rows.Count.ToString() + ); class2.LogMessageToFile(); table2 = dataTable; } catch (OleDbException exception) { class2 = new ErrorLogClass(); class2.LogCode = 8; class2.LogModule = Query Data Get; class2.LogMessage = An error occured. ( + exception + ); class2.LogMessageToFile(); table2 = new DataTable(); } finally { this.dbConn.Close(); } return table2; } PS. This is why I mentioned  or will you be wanting to keep your source code safe from reverse engineering  Also as a general rule it is not wise to show error details of the database exception this gives insight to hackers wanting to penetrate security via vulnerabilities. It is best just to catch an Exception and log where the exception occurred. Note: I do not expect that database security is an issue here but what I have said above is a general rule of good database design. Regards.

theLizard · Answer

Hi Phil I downloaded the beta of YachtMaster from your site and installed it I have some come constructive criticism well one actually if OLEDB is not registered on the computer you get an error which cannot be closed down without using Task Manager not really good for people who do not know a lot about computers. I have attached an image of the error. You should first check that the requirements for the application have been established during the setup process if something is missing that is needed you should either provide it as an installation option or point to where the required software can be downloaded from. Can I make a suggestion since I got this error message because I do not have OLEDB registered would you consider using ODBC instead of OLEDB since ODBC is part of all windows installations.. Regards...

theLizard · Answer

Hi Phil I am interested in what you are doing I assume you have found this sentance for what you are after. $GPRTE21c0W3IWIDRIVWY32CEDR32-2932BKLD32-I9532-US1BW-32BW-198*69 Also will your product be open source or will you be wanting to keep your source code safe from reverse engineering. I am also pretty sure that NMEA is an international standard.

Sam Hobbs · Answer

I don't know what a NMEA sentence structure is but I assume you are correct that it is standard. There is much more that needs to be done to communicate with Garmin using USB. I don't know what the advantage of USB compared to older serial communications are but I assume there are advantages. If serial works for you then it is easier to use in terms of programming. I had no problems find the driver unless there is a separate driver for use of serial communications over USB for Garmin devices. I did once find something in the Microsoft site about GPS but I did not understand what it is for or does or whatever. I don't remember where it is.

Phillip Seaman · Answer

Sam I am using a Garmin for now but I believe that they all use the same NMEA sentance structure to communicate with other instruments. I guess I'll find out as I go along! I would love it to be a standard! The USB connection is rather trickey as it needs the spacific drivers (32bit or 64bit) which are hard to locate but once installed the usual Serial (Com) port object works fine. Thanks SquireDude

Sam Hobbs · Answer

I tried interfacing with a Garmin using the USB. The documentation was lousy; it was a few years ago so maybe it has been improved. The sample program did not show much. It is unlikely you can find help anywhere else. When you do ask for help be sure to say that it is for a Garmin because anyone that can help will ask so you should save their time spent asking for clarification.