Category Archives: Development

State of #VSCP May 2017

Well, it’s time for a new status update for the VSCP project.

I am still working with the tables interface on the VSCP daemon.  This has taken far more time then I ever expected it to take.  But I want to have it in place and will eventually. One of the reasons for it to take such a long time to implement is that I clean up code and document parts of the system at the same time.  Another reason is that I have some surgery for a bad shoulder last week and that also has slowed things down. Anyway. things move forward, be patient.

The helper lib

I discovered a bad thing I did not think of last week when I worked with the VSCP helper library.  A year ago or so I changed the communication motor from my own work to Mongoose mostly to quickly get SSL working. This was of course a big mistake. I want this code and the resulting library to be free to put in any project, also in commercial project where the source needs to be protected. Mongoose is released under GPL v2 so by using it in this case users of the helper library and helper/interface classes has to share their code.  This is no problem under the development stage of a project. But it is a problem for released works.  I will prioritize this change. Mongoose will be removed from this part.  The problem is not the same for the VSCP daemon and other tools in the package which can live with GPL’d code. Here Mongoose will still be used.

VSCP Classes

An easy way to build clients for the VSCP daemon is to use the some classes available in the VSCP &Friends package.  A sample project and some examples for this is now available here.  As always the other way to make clients for communication with the daemon is to use the VSCP helper library.  A C# library is on the way for this and hopefully we will see more bindings also in the near future.

OK – That was all for now.

Cheers & Have fun!
/Ake

ps My mascot, the frog, was destroyed when the roof fell in here last night, I hope that is not a bad omen…  😉 ds

Important change to the vscpEvent/vscpEventEx structures and timestamp #VSCP

New fields in vscp event structures (vscp.h)

From version 1.12.20.0 a date/time block of the following form

        // Time block - Always UTC time
        uint16_t year; 
        uint8_t month;    // 1-12
        uint8_t day;      // 1-31
        uint8_t hour;     // 0-23
        uint8_t minute;   // 0-59
        uint8_t second;   // 0-59

has been added to the vscpEvent/vscpEventEx structures

This will affect all interfaces that read and write VSCP events. So for the TCP/IP interface which previously used

send head,class,type,obid,time-stamp,GUID,data1,data2,data3....

will now have the form

send head,class,type,obid,datetime,time-stamp,GUID,data1,data2,data3....

where datetime is the UTC date/time in ISO standard form YYYY-MM-DDTHH:MM:SS

It is possible to let the interface set this time to the current UTC time by leaving the item blank.

So

send 0,20,3,0,,,-,0,1,35

will set the current UTC time (and timestamp) in the interface when the event is received.

But on the other hand

send 0,20,3,0,"2001-11_02T17:00:01",,-,0,1,35

will use a specific date and time. Note that timestamp is set by the interface in this case.

The change affect a lot of code. Expect some instability. The helper lib has been changed appropriately so if using it your code should be safe.

timestamp

It’s a bit of  confusion before if timestamp has been set in microseconds or milliseconds.  Now this is definitely fixed at microseconds.  An unsigned long is enough to keep track of about 71 minutes before it roll over. This was considered a bit low before the date/time structure was introduced but is more than enough now.

When timestamp previously was sent with a value of zero it was set to UTC microseconds of the interface. This is not the case anymore.  Leave the field blank instead if you want the interface to set the timestamp.

Resend to the VSCP mailing list

I have previously resent blog entries here to the mailing list when I though they could be of interest for the mailing list audience.  This will be the last one resent this way. If you are interested in blog posts about VSCP subscribe to this blog. An RSS reader is another option.