Page 1 of 1

OTGW communication to Boiler violates OT Protocol v2.2

PostPosted: Sun Nov 03, 2019 6:45 pm
by marsm2m
Hello,

HW from Nodo Shop.
PIC16F88P with FW gateway_v4.2.5.hex
OTGW in Gateway mode
Boiler: TERMET WINDSOR 25
Thermostat: Honeywell CT11011

Issue:
As presented on the attached waveform (OTGW425_to_Boiler_Tx_feedback.png), pulses are not as specified in the "Opentherm Protocol v2.2", chapter "3.4.2 Bit Rate and Timing".
Second waveform (OTGW425_Boiler_Response.png) presents response from Boiler.
Although it works, is it possible to be fixed in the OTGW firmware? Very short pulses produces EMI incompatibilities and shall be avoided.
If nobody tried to fix it then I could try but have only sources for 4.2.4. Where sources for 4.2.5 can be found?

Thank You in advance

Re: OTGW communication to Boiler violates OT Protocol v2.2

PostPosted: Sun Nov 03, 2019 10:46 pm
by hvxl
It is unclear to me where you observed those spikes. But if you can improve the OTGW, I'm all for it. The 4.2.5 sources can be found on the OTGW download page.