I searched forum and found someone inquiring on HOW to send commands to a VELLMAN MML16R.
The post was locked by support stating it is not a project/kit.
If we can’t talk about it here where can we get support?
Vellman sells it.
I used a port sniffer and created variables to match then wrote a bash script with many, many variables to send predefined statements to it.
Better if Vellman provided source code for Vellman provided application that came with sign from Vellman. I’m trying to figure out the CRC that is sent to sign. Can’t seem to match it.
So this forum is a dead end cause we can’t talk about the Vellman MML16R which is a project to me but not to this form moderator.


As Velleman won’t give support on this because no kit, then you are free to post your question on other electronics fora. Keep in mind that Velleman also sells things from other companies, like this MML16. So Velleman does not have all the documents or information you need and this way, they can’t help you further. For not Velleman projects, you should use the support link you’ll find on the product page of the product. They will give you the information they have but they can’t do much more.
For you it may be a project but the Velleman engineers get payed by the hour … and you know the hourly cost of an employee in Belgium is very high! :wink: They really don’t have the time and Velleman does not have the money to put all their engineers on projects of the customers. Hope you can understand this.
Good luck!


Understood, thus I have to reverse engineer it.


Yes, if Velleman can’t send you more information because they have no more information, you’ll need to do something like reverse engineering, if possible because in these consumer devices, a lot of cheap microcontrollers are used that contain all the functionality in 1 IC.


Hi there “niety”,

Me too, I’m involved in a project having to send messages to a MML19R board from an arduino.

You know you can use software like the fine “Eltima Serial port monitor” or an X modem cable and a terminal for reading the commands. But you may also have noticed that the messages sent from their software, they have a sort of CRC hex number embedded (right at the end of your text -two bytes long) where I have to guess what algorthm they use :).

Have you digged further in it? :slight_smile:

As soon as I discover something I can let you know. Or maybe you already did it.

Good luck,




You can post your question in the following link.


Hi, I figured out the hex number needed thanks to this PDF : that hex "denotes the Xor Result of the data content(Data Package). "

So in Java I did this :
public static void main(String[] args) {
String myCommand = “<L1> Text here”;
byte res = 0;
for(int i=0; i<myCommand.length(); i++){
res ^= myCommand.charAt(i);
//String checksum = hex(res);
String hex = Integer.toHexString(res).toUpperCase();
String actualCommand = “<ID00>” + myCommand + hex + “<E>”;