Category Archives: Development

State of #VSCP “things”

Time for a status report again.

My hope was to have a LTS release ready before the summer but I never reached that point.  But things are what they are. There are mainly two reasons for the delay. First I don’t want to rush some big changes in the core structure that force me to do incompatible updates later with code needed for update paths. This mostly relate to the database. Next I want to move as much of the code as possible to MIT licensed which means I have to remove and rewrite some stuff.   Hopefully something will be available soon after the summer.

The multicast channel support is now fully implemented.  This means one can set up groups on the VSCP multichannel group that act as subnets using a specific port.  AES128/AES192/AES256 encryption is available. The multicast announce is also fully in place now. Python and c/c++ samples available.

A  new UDP interface has been implemented. Also here are AES128/AES192 and AES256 encryption available. Python and c/c++ samples available.

Support classes for encryption and frame packaging has been added to the vscphelper lib to make it easier to handle this new functionality.

pyvscp is a pip installable Python module that add VSCP functionality to Python. The main interfaces is in place but more will come and also more documentation. It’s very easy to interface the VSCP server and VSCP with this module. I personally love it.

The libvscphelper library is now packaged as a deb as the first component that will be available on this form. It is needed to be installed to use most of the functionality of pyvscp.  VSCP Works and the vscp server till also be packed in their own deb’s for easy installation.

node.js bindings installable with npm is next and I know there is c# bindings brewing also. Probably have to dig into Java soon also if someone does not volunteer for that job.

A lot of other this to have hap-end of course.

Now I will go on a four-week leave. I am not used to that long vacations and right now I don’t actually know how to survive such a long time without coding. But I have promised my wife to try to to be honest I probably need it. I will check mail occasionally though but wil probably not answer mails on a daily basis.

So all friends out there. Have fun!

#VSCP New Multicast and UDP interfaces

From version 1.12.26 the muticast channel interface is available. Also a new UDP interface is available.

With the multicast channel interface one can set up groups of Level II nodes that share a common channel for events. Much like a bus like CAN. Frames can be encrypted using AES128, AES192 or AES256.

With the new UDP interface one can set up a receiving interface and several sending interfaces which send UDP datagrams to remote nodes. Frames can be encrypted using AES128, AES192 or AES256.

The settings for the multicast channel interface is here

The settings for the UDP interface is here

The encryption key are under the <security> tag.

Some sample code can be found in the source tree under test/multicast and tests/udp. Not more documentation at the moment I am afraid but I work on that.

Well there are probably some bugs left…


Effect of #VSCP package change

For those of you running head code of the VSCP & Friends package

Remember to build the full VSCP & Friends package after checking it out from git and then compile all files and do a “make install” as root. If you don’t do this drivers and the VSCP server (the daemon) may use different package formats which will   corrupt memory and probably make the VSCP server and the rest of the code unstable.


IMPORTANT! #VSCP configuration change

From version Magnesium the configuration file format has changed. A lot of things have moved out from the <general> section up to the top-level.  Refer to the distribution vscpd.conf for full info.

Configuration file reading order has changed as well. Now things work as the following

  1. Read the <general> tag information from the XML configuration.
  2. Read configuration from the database.
  3. Read the full XML configuration.

This change makes it easier to have a safe setting in the XML configuration file that can’t be overwritten by changes in the database. The importance of this will be more clear when settings can be changed in the administrative web interface.


/Ake Hedman

ps There is a lot of bumblebees here on the VSCP hill right now, more than ever before. Must be a sign… 😉 ds

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!

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 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.


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.


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.

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