Victor-Mo
commented
3 years ago Hi @grunz-ux ,
Very interesting project ! Because of issues #10 and #13 I have been doing some reverse engineering of the Moduline 300 thermostat. The moduline 300 has a discreet interface, the older modulines use a custom chip. I always assumed the iRT bus was very similar to the EMS bus. A current / voltage bus. But last week I came to the conclusion the iRT is a current loop only bus. (I feel a bit stupid not think of this earlier because also the Nefit service tool has a series connection...)
From what I could measure the bus is idle at 11 mA (serial mark state (1)). When the boiler wants to transmit the loop current is increased to 23 mA (serial space state (0)), if the thermostat wants to transmit the loop current is reduced to 3mA (serial space state (0)). Because the moduline 300 (and others) try to maintain +/- 5.5 Volt across their inputs it becomes very difficult to detect the signals as voltages.
I have been experimenting with an opto-coupler (ltv817) in line (series connection) with a moduline 300. That also seems to give very good results. But it needs some more tweaking because the current through the optocoupler is a bit high, causing the output to saturate.
I should remove the python scripts, they are for the EMS bus.
If I run the data you collect with the Pi through my test program it correctly decodes it, so the interface works !:
(00:00:06.857) irt_rawTelegram: 33: 01 01 FE 73 73 52 52 25 25 43 43 78 78 01 01 FF FF AD AD 01 01 46 46 25 25 19 19 73 73 52 52 25 25 43 43 78 78 07 07 FF FF A1 A1 07 07 4D 4D 00 00 9D 9D
(00:00:06.857) : 01:46 07:4D 73:52 78:07
(00:00:06.857) irt_rawTelegram: 2B: 01 01 FE A4 A4 52 52 25 25 94 94 1F E0 A6 A6 01 01 FF FF 73 73 16 E9 A8 A8 46 46 25 25 B0 B0 40 BF A3 A3 52 52 25 25 93 93 53 AC
(00:00:06.857) : 01:46 07:4D 73:52 78:07 | A3:53 A4:1F A6:16 A8:40 -H
(00:00:06.857) irt_rawTelegram: 35: 01 01 FE 82 82 52 52 25 25 B2 B2 84 7B 83 83 01 01 FF FF 56 56 02 FD 93 93 46 46 25 25 8B 8B 00 FF 90 90 52 52 25 25 A0 A0 A7 58 C9 C9 07 07 FF FF 10 10 01 FE
(00:00:06.857) : 01:46 07:4D 73:52 78:07 | 82:84 83:02 90:A7 93:00 A3:53 A4:1F A6:16 A8:40 C9:01 -H
(00:00:06.858) irt_rawTelegram: 31: 01 01 FE 97 97 52 52 25 25 A7 A7 03 FC 84 84 01 01 FF FF 51 51 55 AA 8A 8A 46 46 25 25 92 92 FE 01 73 73 52 52 25 25 43 43 78 78 06 06 00 00 74 74
(00:00:06.858) : 01:46 07:4D 73:52 78:06 | 82:84 83:02 84:55 8A:FE 90:A7 93:00 97:03 A3:53 A4:1F A6:16 A8:40 C9:01 -H
(00:00:06.858) irt_rawTelegram: 2F: 01 01 FE 81 81 52 52 25 25 B1 B1 46 B9 DE DE 01 01 FF FF 0B 0B F7 08 73 73 52 52 25 25 43 43 78 78 05 05 04 04 62 62 05 05 04 04 00 00 0D 0D
(00:00:06.858) : 01:46 05:04 07:4D 73:52 78:05 | 81:46 82:84 83:02 84:55 8A:FE 90:A7 93:00 97:03 A3:53 A4:1F A6:16 A8:40 C9:01 DE:F7 -H
(00:00:06.858) irt_rawTelegram: 33: 01 01 FE 73 73 52 52 25 25 43 43 78 78 01 01 FF FF AD AD 01 01 46 46 25 25 19 19 73 73 52 52 25 25 43 43 78 78 07 07 FF FF A1 A1 07 07 4D 4D 00 00 9D 9D
(00:00:06.858) : 01:46 05:04 07:4D 73:52 78:07 | 81:46 82:84 83:02 84:55 8A:FE 90:A7 93:00 97:03 A3:53 A4:1F A6:16 A8:40 C9:01 DE:F7 -H
(00:00:06.858) irt_rawTelegram: 2B: 01 01 FE A4 A4 52 52 25 25 94 94 1F E0 A6 A6 01 01 FF FF 73 73 16 E9 A8 A8 46 46 25 25 B0 B0 40 BF A3 A3 52 52 25 25 93 93 53 AC
(00:00:06.858) irt_rawTelegram: 36: 01 01 FE 82 82 52 52 25 25 B2 B2 84 7B 83 83 01 01 FF FF 56 56 02 FD 93 93 46 46 25 25 8B 8B 00 FF 90 90 52 52 25 25 A0 A0 A7 58 C9 C9 07 07 FF FF 10 10 01 FE 02
EMS-ESP system stats:
System logging set to Jabber
LED is off, Listen mode is off
Boiler is enabled, Thermostat is enabled, Solar Module is disabled, Mixing Module is disabled, Shower Timer is disabled, Shower Alert is disabled
EMS Bus stats:
Bus is connected, protocol: Buderus
Rx: # successful read requests=40, # CRC errors=0
Tx: Last poll=0.500 seconds ago, # successful write requests=0
Boiler stats:
Hot tap water: off
Central heating: active
Warm Water activated: on
Warm Water selected temperature: 0 C
Warm Water current temperature: 64.0 C
Warm Water 3-way valve: off
Selected flow temperature: 0 C
Current flow temperature: 37.0 C
Return temperature: 30.0 C
Gas: on
Boiler pump: on
Fan: on
Ignition: off
System service code: -H (83)
Heating temperature setting on the boiler: 70 C
Outside temperature: 0.0 CI think the reason it does not work in combination with the esp8266 is that I use the serial interface in inverted mode, But if you change line 13 in irtuart.h from:
#define IRTUART_CONFIG_PASSIF (0x1C | (1 << UCRXI) ) // 8N1 (8 bits, no stop bits, 1 parity), invert Rxd
to:
#define IRTUART_CONFIG_PASSIF 0x1C) // 8N1 (8 bits, no stop bits, 1 parity)
and then recompile, it should work.
grunz-ux
erhapp
mletenay
bbqkees
Hi,
Nice work on figuring out the iRT protocol! I want to monitor my EcomLine Classic HRC30 UBA4000 (1997 o_0) with Moduline 300 thermostat so I made a circuit that listens to the bus using a series-resistor instead of parallel with the thermostat, should be more robust. See here;
Results are good, this is what I get on the scope;
So I've connected it to a pi and used minicom to read out the following messages;
I didn't look into the telegrams in detail but in general they match your description. I tried to get your python converter running but no luck so far. I built your code and uploaded to a NodeMcu Lolin esp8266 v3, set tx mode to 4 but it doesn't interpret the telegrams correctly. Can you tell why?