Firmware version 4.0 has been released.

[mike7]

You make it sound complicated. You are aware that instructions are available in the readme.txt file included in the gateway sources and at http://otgw.tclcode.com/otmonsrc.html?

patch is working, thanks
will try to update firmware ... a bit later

[mike7]

That's correct. I initially only implemented the SR command for message IDs the gateway didn't handle specially. Since it is using the values from MsgID 48 and 49, the SR function doesn't work for these message IDs. You may be able to add this functionality by replacing the 2nd and 3rd "return" of the MessageID48 and MessageID49 subroutines by "goto WordResponse" (untested).

Tested(still testing), it's working, thank you

[nextdomo]

Hi Schelte,

I have the latest beta (4.0b5) running for a while now and I am about to update to 4.0.1. A very interesting update is the support for the On/Off thermostats.

I've read the following information in the stand-alone section of the website:

As indicated, the gateway by default will instruct the boiler not to do any heating when the thermostat terminals are left open. However, when the terminals are tied together, the gateway sends its internal maximum central heating setpoint value to the boiler and sets the CHenable bit in MsgID 0. This allows the use of a simple on/off thermostat in combination with the gateway and an opentherm boiler.

As I understand this correctly, the On/Off thermostat is connected to the OTGW thermostat terminals and wil cause the 'open' and 'tied together' states of these terminals when he wants the boiler to be heated (or not)?

Also how does the gateway handle the thermostat setpoint (TT=temperature or TC=temperature)? Does he ignore this as he can't communicate with the Thermostat?

On the other side, might it also be interesting to control a on/off boiler in combination with an OpenTherm thermostat? Is it possible to capture the thermostat commands if he wants to control the boiler and convert them to On/Off messages? I can see the value for this because you can still use the temperature setpoint commands (TT/TC) with an On/Off boiler. And you can still use the temperature control algorithm of the thermostat. I do can imagine this would also be an addition to the hardware.

[hvxl]

As I understand this correctly, the On/Off thermostat is connected to the OTGW thermostat terminals and wil cause the 'open' and 'tied together' states of these terminals when he wants the boiler to be heated (or not)?

Correct

Also how does the gateway handle the thermostat setpoint (TT=temperature or TC=temperature)? Does he ignore this as he can't communicate with the Thermostat?

When an on/off thermostat is connected to the gateway, the commands that affect the interaction with the thermostat have no effect. In addition to the commands you mentioned, that also includes SC, SR, CR, KI and UI.

On the other side, might it also be interesting to control a on/off boiler in combination with an OpenTherm thermostat? Is it possible to capture the thermostat commands if he wants to control the boiler and convert them to On/Off messages? I can see the value for this because you can still use the temperature setpoint commands (TT/TC) with an On/Off boiler. And you can still use the temperature control algorithm of the thermostat. I do can imagine this would also be an addition to the hardware.

You could probably attach a relay to one of the LED/GPIO pins and control an on/off boiler with that. But the firmware would have to be adapted to generate responses to the thermostat. I have personally no interest in developing such an enhancement for the gateway.

[hvxl]

Firmware 4.1 is now available on the web site. It has the changes I suggested earlier in this topic for the SR command to work for MsgID 48 and 49. It also has a new serial command to force a thermostat model in case auto-detection gets it wrong.

You will also need the new OTmonitor version to be able to transfer your old settings to the new firmware (and it has a new button to list the transferred settings after the download).

[mike7]

Schelte,

thank you for your work & support. I have several issues and feature requests

I want to mention, "SR, UI pairs for ids 48 and 49" should be send after couple of minutes on gateway start/restart, otherwise they don't have effect. (it was tested on patched version, not on 4.1).

Thermostat connected/ disconnected mqtt messages from otmonitor have retain flag set. On start/restart gateway doesn't send "connected" message, so if you turn off gateway & restore connection, you will stay with "disconnected" in the queue (the error messages is different story, I will manually clear error after checking and correction) . I found the only way to check thermostat connection, it is checking for lack of T messages, is it possible to add command to firmware or otmonitor to check?

Could you please suggest scheme or firmware change for setting gateway to "stand-alone mode" with still powering thermostat? The idea is to set thermostat to comfort mode, but control a boiler on eco mode with another algorithm, I don't need accurate control in such case. For several reasons I can't change my thermostat right now, it will be the solution for me.

Is it possible to add to firmware support for msg id 11 with read/write support?

[random]

Firmware 4.1 won't run properly for me. After the update through otmonitor I was unable to get a proper output from the UART. I've reverted back to 4.0.1 which is working fine.

With firmware 4.1, my OTGW was talking some garbage. Just once it learned to talk properly again (see screenshot). But most of the time it kept outputting garbage. I am connected through USB.

OTGW_after_update.png (56.56 KiB) Viewed 11724 times

Has anyone else successfully updated to 4.1? What might have gone wrong for me here?

[hvxl]

thank you for your work & support. I have several issues and feature requests

Please report issues and feature request when you encounter them. Don't sit on them until just after I release a new version. Obviously the new version won't have features and fixes for bugs I don't know about.

I want to mention, "SR, UI pairs for ids 48 and 49" should be send after couple of minutes on gateway start/restart, otherwise they don't have effect. (it was tested on patched version, not on 4.1).

Unlikely. The code will do exactly the same thing if you give the commands immediately after a restart or several minutes later. The gateway will always request ID's 48 and 49 once for its own administration. But apart from that, the SR and UI commands do what they are supposed to do, irrespective of when they have been issued.

Thermostat connected/ disconnected mqtt messages from otmonitor have retain flag set. On start/restart gateway doesn't send "connected" message, so if you turn off gateway & restore connection, you will stay with "disconnected" in the queue (the error messages is different story, I will manually clear error after checking and correction) . I found the only way to check thermostat connection, it is checking for lack of T messages, is it possible to add command to firmware or otmonitor to check?

I will fix that in a future version of otmonitor.

Could you please suggest scheme or firmware change for setting gateway to "stand-alone mode" with still powering thermostat? The idea is to set thermostat to comfort mode, but control a boiler on eco mode with another algorithm, I don't need accurate control in such case. For several reasons I can't change my thermostat right now, it will be the solution for me.

You can control the domestic hot water enable option (comfort/eco mode) with the HW command independent of the presence of a thermostat.

Is it possible to add to firmware support for msg id 11 with read/write support?

There is already read support for TSP's. Write support would require a substantial amount of code. Given the limited code space still available in the PIC, I have no plans to add something big with what I consider low usefulness. If you want it, you are going to have to add it yourself.

[mike7]

Could you please suggest scheme or firmware change for setting gateway to "stand-alone mode" with still powering thermostat? The idea is to set thermostat to comfort mode, but control a boiler on eco mode with another algorithm, I don't need accurate control in such case. For several reasons I can't change my thermostat right now, it will be the solution for me.

You can control the domestic hot water enable option (comfort/eco mode) with the HW command independent of the presence of a thermostat.

I'm using hot water control, very useful feature, thank you.
I want to control central heating, my thermostat doesn't support room setpoint override. Sorry for confusion.

[hvxl]

You can do that too, with or without a thermostat connected. The only difference is that with a thermostat connected, the thermostat controls the sequence of messages being sent to the boiler. Without a thermostat the gateway makes up its own sequence.

[mike7]

I want to mention, "SR, UI pairs for ids 48 and 49" should be send after couple of minutes on gateway start/restart, otherwise they don't have effect. (it was tested on patched version, not on 4.1).

Unlikely. The code will do exactly the same thing if you give the commands immediately after a restart or several minutes later. The gateway will always request ID's 48 and 49 once for its own administration. But apart from that, the SR and UI commands do what they are supposed to do, irrespective of when they have been issued.

Will recheck with latest firmware, unfortunately I can do only 2-3 weeks later. I attached the log with the issue for msg 48 gateway didn't request for "its own administration", for msg 49 after first response I've got known id. I don't have a log, but I was in situation when both msg 48 & 49 were known ids.
I'm OK with my workaround, I reported just for information.

[hvxl]

Hang on, I think I know what might be happening. When the gateway requests ID's 48 and 49 "for its own administration", it gets a reply from the boiler and then marks the ID's as known again. Sorry for not realizing that earlier. I will have to think about how to prevent that.

[mike7]

You can do that too, with or without a thermostat connected. The only difference is that with a thermostat connected, the thermostat controls the sequence of messages being sent to the boiler. Without a thermostat the gateway makes up its own sequence.

I like your sequence better , in my scenario thermostat will always send maximum setpoint with a lot of useless messages.
May be it will be possible with transistor switch controlled by gpio, but I don't have enough knowledge ....

[dirkmans]

I've got a Ferolli boiler with an Isense thermostat.
The boiler doesn't support smart power, so I have to use batteries in the thermostat for the backlight.
Can someone tell me if I connect the OTGW, can I use the smartpower function on the thermostat?

[hvxl]

Confirmed. With the OTGW in between you don't need batteries in the iSense anymore for the backlight to work.