Good afternoon all,
I live in The Netherlands and have a small VelBus at home. Currently 4 glaspanels and 4 shutter modules. More modules will be added soon. Just before we started the complete renovation of our house, we discovered the VelBus edge lit glass panels at the BatiBouw fair. Both fell in love with the switches and once the renovation started, I installed approx 100 m of cabling for the purpose of domotics.
The VelBus is connected to OpenHab, which in turn also uses Zigbee (Ikea lamps, aqara motion detectors), Wifi (Sonoff modules) and 433 MHz KlikAanKlikUit. Kind of a mixed system but it works great.
The plan for the upcomming years is to converted more to VelBus, as it is very realiable and does not need a Raspberry to work. The RPI does do the automation, but in case of failure / crash, the boss (yes, my wife) wants to be able to control the lights. So that if where the KlikAanKlikUit has a +1. It can be controlled with a dedicated remote at all times. VelBus has the same advantage, but it kind of expensive (in fact very expensive, so 1 module at a time). That is why there is a slow convertion planned.
As I do like to learn how things work, I now set my self some goals of understanding the Velbus. As it is CAN based and the protocol is more or less published, step 1 is to be able to understand what is happing. I played with the VelBusLink software.
Also installed the python VelBus module and even was able to fake a module using python. More on that later
BTW: I use the VelServ on my RPI.
I grabbed an arduino & MCP2515 chip, and got that working very fast. but have difficulties finding the optimal settings for the MPC2515.
When I trigger the output of module “3”, my Adruino logs following:
(already calculated the CAN ID back to velbus ID (/2 & 0xff)
ADDR, LENGTH, DATA_0…DATA_N
03 02 01 12
03 07 DA 01 FE 00 00 01 AB
In the first row, everyting OKE
In the sencond row, the data is shifted 1 bit (not byte) when I compare with VelBusLink output (and datasheet).
So after the “7” (number of bytes), everything is shifted 1 bit.
Should be according VelBusLink:
03 07 ED 00 FF 00 00 00 D5
The 16k6 baudrate is not standard, and I had to guess the CNF1, CNF2, CNF3 values using an online calculator. But there are many variations of these 3 values that give the same baudrate but have different means for other settings.
Does anyone have a reliable set of configuration values for the MCP2515 (at 8 MHZ)???