Error 03 in response to every OT message in gateway mode

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emmeesse68
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Error 03 in response to every OT message in gateway mode

Post by emmeesse68 »

Hello forum,

something strange is happening to my OTGW, that's sitting between my Ferroli BlueHelix Pro 32c boiler and my Honeywell EvoHome "thermostat".

Everything used to work fine for a few weeks. Now I'm out for the weekend and as I remotely logged into my system I saw flat lines in the graph reading unusual values. Logging was an endless repetition og thermostat request and Error 03. Nothing from the boiler.

I tried issuing a GW=R command to no avail. Gateway actually reset itself but errors kept coming.

I tried switching to Monitor mode and everything seems to be working OK. Switching back to Gateway mode makes the errors come back. So now it's basically working fine in monitor mode only.

Looking at the graph after switching to Monitor mode made me notice the heating system was on, while my heating control was set to be off. Zones were shut, but boiler kebt burning for nothing, basically wasting energy.

This is causing a pretty serious reliability issue, IMHO, since any reset would switch my OTGW to Gateway mode, preventing communications between boiler and thermostat. Tonight when I get back home I think I will disconnect my OTGW to check more in-deep... meanwhile, any advice is good!

Thanks

M
hvxl
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Re: Error 03 in response to every OT message in gateway mode

Post by hvxl »

I would try if changing the reference voltage gives an improvement.
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emmeesse68
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Re: Error 03 in response to every OT message in gateway mode

Post by emmeesse68 »

It worked, thanks.

I had to reduce from 1.458V as I set it and used to work, to 1.042V. Anything higher would just trigger error 03 to any message, lower (0.833v) seems to be causing messages to take twice the time. Lowest (0.625v) breaks communications again.

Just as a reference, a few days ago I already did some experimentation with reference voltage, and I remember it was breaking comms lowering to 0.833v or lower. But it used to work without problem setting it higher (1.458V was OK).

Since then ran 24x7 until last friday... logs show an increase in error 03 occurrence after 15:40, in an hour or so it went completely nuts without changing any parameters.

I think I'll check diagnostics Tomorrow night after work. Since then I'll keep an eye on it, now it's working in gateway mode with Vref set to 1.042V. What could be happened to change VRef sensitivity this much?

Thanks

M
emmeesse68
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Re: Error 03 in response to every OT message in gateway mode

Post by emmeesse68 »

I tried increasing Vref further and, curiously enough, setting it above makes it work again! So, setting Vref = 1.667V works, and it could be increased up to 2.083V. Setting it to 2.292V or higher, would break comms.

Summarizing,

Vref = 0.625V NO COMMS
Vref = 0.833V slow communications
Vref = 1.042V OK
Vref = 1.250V or 1.458V makes Error 03 appear at every T command. No B responses.
Vref between 1.667V and 2.083V OK
Vref = 2.292 or higher NO COMMS.

While I could reasonably expect comms to be broken below a min. threshold and above a max., I can't figure out what happens in the 1.250 to 1.458V window...

Ideas? Might it be some faulty component in the comparator circuitry?

Thanks again!

M
hvxl
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Re: Error 03 in response to every OT message in gateway mode

Post by hvxl »

Very strange indeed. Even more so given that it works in monitor mode. That's using the same hardware and decoding routines. The only difference is that the comparators are configured to a different mode. Is it feasible for you to try another PIC?
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emmeesse68
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Re: Error 03 in response to every OT message in gateway mode

Post by emmeesse68 »

...I might buy a PIC locally but I don't have a PIC programmer, nor I know of a local service. Buying from the Netherlands could take a bit of time. I might try to reflash the diagnostic (do you think it may help?) and carry out some test.

By the way, is it better to flash with the gateway disconnected from thermostat/boiler, or it's not important?

Yesterday I tried to set my OTGW in monitor mode and retry all Vref levels. As soon as I tried to set it to 0.625 my gateway signaled something like "GTW has been reset!" and I lost connection. Being unable to change Vref again, I tried stopping/starting USB/serial related drivers on my linux box, and, as a last resort, I tried to reboot the box itself. None of the above worked, when I arrived home late in the night I had to unplug my OTGW to make it respond to commands again, no commands flowing from my "thermostat" to my boiler (so I had a nice and cold bed waiting for me :-( ). Does anybody know of some way to add some PC interface to the reset button, to reset remotely if such a situation happens again...?
hvxl
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Re: Error 03 in response to every OT message in gateway mode

Post by hvxl »

If you don't have an easy way to program a PIC, trying a different one falls outside the category of what I call feasible.

The diagnostics firmware uses the same comparator configuration as monitor mode. You reported that things work OK in monitor, so I don't expect we will get much useful information from the diagnostics firmware for this problem. But you never know.

You can flash the gateway with the thermostat and boiler attached. That's what I always do.

Does your USB-serial device support sending a break? That might be a possibility to reset the gateway. Of course, the gateway should be in some reasonable state for that to work. If it is completely stuck, chances are slim that it will be able to detect the break and act accordingly.
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emmeesse68
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Re: Error 03 in response to every OT message in gateway mode

Post by emmeesse68 »

hvxl wrote:The diagnostics firmware uses the same comparator configuration as monitor mode. You reported that things work OK in monitor, so I don't expect we will get much useful information from the diagnostics firmware for this problem. But you never know.
OK I might try when I find an hour to spare. I ordered some components to improve my OTGW (a few LEDs, headers for the GPIO, ... and connectors to plug/unplug LEDs, GPIO, boiler and thermostat without needing a screwdriver or even opening the box) so I'm planning to detach it from heating system (I might try optimizing R8 to improve timing symmetry, as we were discussing in a different post).
hvxl wrote: You can flash the gateway with the thermostat and boiler attached. That's what I always do.
Thanks, since I did it like you say I was afraid it could have caused a bad flash...
hvxl wrote:Does your USB-serial device support sending a break? That might be a possibility to reset the gateway. Of course, the gateway should be in some reasonable state for that to work. If it is completely stuck, chances are slim that it will be able to detect the break and act accordingly.
I was thinking of some other device, some cheap USB relay that I could plug into my computer and connect to my OTGW reset headers... Ever seen anything like that?
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Re: Error 03 in response to every OT message in gateway mode

Post by hvxl »

emmeesse68 wrote:I was thinking of some other device, some cheap USB relay that I could plug into my computer and connect to my OTGW reset headers... Ever seen anything like that?
You mean something like this? That should work.
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emmeesse68
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Re: Error 03 in response to every OT message in gateway mode

Post by emmeesse68 »

hvxl wrote:
emmeesse68 wrote:I was thinking of some other device, some cheap USB relay that I could plug into my computer and connect to my OTGW reset headers... Ever seen anything like that?
You mean something like this? That should work.
Yep something like that... but I think I may look for something with more than one relay (saw something on ebay with up to 8 channels) to get more into home automation. I found something connected via ethernet, bluetooth or even wifi that would make easy placing them away from computers and closer to controlled devices.

In the beginning I was actually thinking of something even simpler, like connecting a transistor wirh C and E between OTGW reset headers and B driven by a serial adapter like the Prolific cable that I use for the OTGW itself... A capacitor and a pull-down resistor on B would prevent the OTGW to be reset by the first "1" sent on the serial, so you'll have to send enough 1's on the serial to charge the capacitor faster than the pull-down would discharge... I already have the Prolific cable and a few old transistors, as soon as I get my test boards I could give it a try, just for fun... even if it might be even more expensive than an USB relay!
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