Protocol decoder:easymatic
| File:Easymatic.jpg | |
| Name | EASYMATIC |
|---|---|
| Description | Asynchronous, serial bus, differential |
| Status | planned |
| License | GPLv2+ |
| Source code | decoders/uart |
| Input | logic |
| Output | Easymatic protocol |
| Probes | — |
| Optional probes | Thermostat, Boiler |
| Options | invert_thermostat, invert_boiler |
The easymatic protocol decoder can decode the thermostat Easymatic bus protocol used by De Dietrich.
Hardware
Differential link
The easymatic is linked to the boiler with two wires. This link can feed power to the easymatic. Easymatic can have two R4 accu in order to save data if the power cut. Boiler power is a 24V modulated with communication power.
[To be confirmed] The hardware is similar to OpenTherm Specifications : - differential link - about 24V - tension modulation for boiler - intensity modulation for thermostat (easymatic) ?
In order to link with a logic analyzer Saleae Logic an interface must be done.
Protocol
Uart baased
Whereas OpenTherm use Manchester code, the easymatic seems to be based on Universal Asynchronous Receiver Transmitter (UART). It's a : - 1200 bauds communication. - 8 bits of data - no parity - one stop bit
The bit order of the 8 data bits is LSB-first.
Idle state
[TO be define]
details
[To be discovered and detailed]
Frames are repeated twice
To be define : how an order is send