using ds18b20 for return water temp

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Re: using ds18b20 for return water temp

Post by hvxl »

Well done. I can imagine you had some anxious moments doing that. 15 minutes is a very long time for flashing the firmware.

Loading new firmware should be possible without the need to manually reset the PIC. However, if you disconnected the gateway from the boiler before doing the procedure, OTmonitor will indicate that you need to manually reset the OTGW. The reason for that is that it doesn't know which firmware is running, so it doesn't know if it can reset the OTGW via a command. OTmonitor only recognizes that the regular firmware is running when it detects the first response from the boiler. It then sends the PR=A command to get the exact version. If the OTGW is disconnected from the boiler, you can manually run the PR=A command to make OTmonitor aware of the firmware version. With any recent firmware, it will then know it can command the OTGW to restart.

Without that knowledge, you performed exactly the correct procedure: Only reset the PIC, not the whole OTGW. Establishing the WiFi connections takes too much time and the window for starting programming mode will have passed before the connection is restored.

But next time you can just leave the thermostat and boiler connected to the OTGW. During programming it switches its internal circuitry to monitor mode, so the thermostat and boiler can continue to communicate.
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Re: using ds18b20 for return water temp

Post by WimN »

With the patched version of the OTGW firmware it looks like the modulation level is not reported correctly.
Is it possible to upload the v4.2.7 source onto your website so I can use the most recent version?

Thanks!
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Re: using ds18b20 for return water temp

Post by WimN »

You have a new version released: 4.2.8.1. Is it possible to have the source of that version available for download so I can patch it to be used with the temperature sensor for the return water temperature?
Thanks!
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Re: using ds18b20 for return water temp

Post by hvxl »

Firmware version 4.3 is on its way. I plan to publish the sources again for that version.

Firmware 4.2.5 was released over 5 years ago and all that time people seemed to be quite happy with it. Only recently a few small new features have been added on request of individual people. By my calculation, that means that at most 3 people have a real interest in a firmware newer than 4.2.5. It's too much work to make a source package for a possible audience of 3, none of whom have actually asked for the sources.
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Re: using ds18b20 for return water temp

Post by WimN »

Ok, thanks. Looking forward to version 4.3. When released, is it possible to post a message in this forum?
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Re: using ds18b20 for return water temp

Post by hvxl »

Firmware version 5.0 has a command to select whether an external temperature sensor represents the outside temperature or the return water temperature.
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Re: using ds18b20 for return water temp

Post by WimN »

Hello Schelte,
Thanks, this is great!
On my Pi I've installed the new otmonitor software which now reports version 5.0, so that's ok. Using the new otmonitor I've upgraded the firmware on the OTGW which worked perfectly, it only tooks a minute or so and worked at the first attempt. The PR=A command reports version 5.0.
I'm using the OTGW in monitor mode.
With the I/O pins command I set for Vcc and Temp sensor. When I use the PR=G command it reports '2 7' which should be ok. Then I used the 'TS=R' command to select the return water temperature.
The 'PR=D' command reports 'D=R' which should be ok.
But the problem is that the outside temperature is reported as '9.00' which is not correct and the Return water temperature is reported is '???', so what's is wrong???
And all the LED's are off. When I connect the power to the OTGW you see a short flash and that's it.
Tried flashing the firmware again, same result.
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Re: using ds18b20 for return water temp

Post by WimN »

For test I've flashed the patched 4.2.5 version and after a few attempts that worked. After a power cycle all LED's are ok and the return water temperature also works.
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Re: using ds18b20 for return water temp

Post by hvxl »

As you indicated: You are using the OTGW in monitor mode. That means that the OTGW directly passes messages on between the thermostat and the boiler, without any modifications. So, both the outside temperature and the return water temperature you see must be what the boiler reports. If you want the OTGW to fill in the return water temperature, you have to allow it to modify messages. In other words, you need to set it to gateway mode.

I'll check the LEDs in monitor mode.
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Re: using ds18b20 for return water temp

Post by WimN »

Not absolutely sure but also checked gateway mode and did not work either. Another strange thing was that when I used the 'PR=' commands it did not always respond. In the log you could see the command but no reply.
Please mention this in the release notes that you should use 'gateway' mode when you want to use the return water temperature.
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Re: using ds18b20 for return water temp

Post by hvxl »

Your report is too vague for me to act on. Please check to make sure that things are fine in gateway mode. Also specify more clearly what you mean by "did not work". What did not work? The LEDs? The return water temperature? In the latter case, provide a log.

I am not going to mention in the release notes that you need to use gateway mode if you want the OTGW to modify messages. That is basic functionality explained on the web site. It doesn't make sense to repeat everything that is explained on the web site in the release notes. Gateway mode is the default. If users decide to change that to monitor mode, I expect them to understand the consequences. If not, they should not mess with the setting.

I checked firmware version 4.2.5. The LEDs behave the same in monitor mode in that version. So, I didn't break it in version 5.0. It was broken all along, apparently without anyone noticing. :shock:
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Re: using ds18b20 for return water temp

Post by Bororo »

As for LED's I can confirm that my setting (below) is working since long time ago without any change (now on 5.0 firmware). (I don't have DS18B20 connected):

LED A: Flame status
LED B: Transmitting an Opentherm message
LED C: Setpoint override
LED D: Boiler requires maintenance
LED E: Central heating status
LED F: Domestic hot water status
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Re: using ds18b20 for return water temp

Post by WimN »

Yes, that's the setting.

After flashing the 4.2.5 version the LED's did not work. after a powercycle they started working. Maybe some inits for the outputs not working?
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Re: using ds18b20 for return water temp

Post by Bororo »

Bororo wrote:As for LED's I can confirm that my setting (below) is working since long time ago without any change (now on 5.0 firmware). (I don't have DS18B20 connected):
...
Actually I should recall this statement. It looks like LEDs are somehow broken.
I'm using Cyril's fork of OTGW (viewtopic.php?f=75&t=11816) with GPIO settings GPIO A=VCC, GPIO B=Tenp Sensor (but sensor is not present) and LED A = Flame status, B=Transmitting OT message, C = Setpoint override, D = Boiler requires maintenance.
Since I don't know when only LED B is working (blinking periodically).

I also have "classic" OTGW with all 6 LED's connected according to info from here http://otgw.tclcode.com/peripherals.html and which I'm using as a backup and unfortunately it's the same - only OT transmitting is blinking.
Both devices are on 5.0.1 firmware with OTmonitor 5.0
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Re: using ds18b20 for return water temp

Post by hvxl »

Sigh. This such a big mess.
  • First of all, the original report was about LEDs in monitor mode. If your LED B is blinking, you must be using gateway mode.
  • Did you actually look at the other LEDs when any of the configured situations was present? I also have LED A configured for Flame state and it definitely lights up when the flame bit in the status message (ID0:LB3) is set. The boiler requiring maintenance hardly ever happens. So it's not strange that that LED is off.
  • If you don't have a temperature sensor connected, don't set GPIO B to Temp Sensor. What do you even expect that to do?
  • Why have you loaded firmware 5.0.1? That was a debug version for another user.
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