OTGW communication to Boiler violates OT Protocol v2.2

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marsm2m
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OTGW communication to Boiler violates OT Protocol v2.2

Post 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
Attachments
OTGW425_Boiler_Response.png
OTGW425_Boiler_Response.png (163.24 KiB) Viewed 2116 times
OTGW425_to_Boiler_Tx_feedback.png
OTGW425_to_Boiler_Tx_feedback.png (137.45 KiB) Viewed 2116 times
hvxl
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Re: OTGW communication to Boiler violates OT Protocol v2.2

Post 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.
Schelte
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