No answer from OTGW USB interface

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breem
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No answer from OTGW USB interface

Post by breem »

Hi all,

I just connected a new assembled OTGW to my boiler, a thermostat and a raspberry running raspbian. As far I can see the OTGW functions as it is supposed to, except I cannot read/write data from / to it. I turned the thermostat so the boiler should turn on. That worked. But in otmonitor I can't see anything at all...

In /var/log/messages I see the following upon connecting the OTGW to the raspberry:
Dec 24 22:07:33 rasp02 kernel: [19339.883297] usb 1-1.2.1: new full-speed USB device number 7 using dwc_otg
Dec 24 22:07:33 rasp02 kernel: [19339.985488] usb 1-1.2.1: New USB device found, idVendor=067b, idProduct=2303
Dec 24 22:07:33 rasp02 kernel: [19339.985553] usb 1-1.2.1: New USB device strings: Mfr=1, Product=2, SerialNumber=0
Dec 24 22:07:33 rasp02 kernel: [19339.985572] usb 1-1.2.1: Product: USB-Serial Controller
Dec 24 22:07:33 rasp02 kernel: [19339.985586] usb 1-1.2.1: Manufacturer: Prolific Technology Inc.
Dec 24 22:07:33 rasp02 kernel: [19339.996800] pl2303 1-1.2.1:1.0: pl2303 converter detected
Dec 24 22:07:33 rasp02 kernel: [19340.001302] usb 1-1.2.1: pl2303 converter now attached to ttyUSB0

So it seems to do something...

How do I start troubleshooting this issue?

Thanks in advance!
hvxl
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Re: No answer from OTGW USB interface

Post by hvxl »

The first step is to make sure otmonitor is connected to your serial device. Go to Options -> Connection and select Serial port and a serial device of /dev/ttyUSB0. Then click Connect. Now in the bottom right-hand corner of the main screen of otmonitor you should have a green icon showing two connected plugs.

If you got that and you don't see any data in the log tab, perform a hard reset of the gateway. Pull the plug if you didn't attach a reset button. Now something should happen. If it doesn't, your USB device is probably not attached correctly to the gateway. Check that the 2 jumpers that you need instead of IC2 are in the correct location and that the USB cable is connected to the correct pins of the RS232 header.
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breem
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Re: No answer from OTGW USB interface

Post by breem »

Hi,

I checked the jumpers and the USB cable pinout. This seems to be as layed out on the instructions. When I perform a reset (otmonitor running and the green plugs visible) I see the following in the log tab:

21:41:08.540399 p

Nothing else appears in the log. At the same time this appears in the log a "Diagnostics" screen pops up allowing me to choose a test to perform.

Any hints?
hvxl
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Re: No answer from OTGW USB interface

Post by hvxl »

And choosing a test works? Then communication is fine. Your gateway is loaded with the diagnostics firmware (I understand that's how they are normally delivered). To switch to normal operation, download the gateway firmware and load it into the gateway.
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breem
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Re: No answer from OTGW USB interface

Post by breem »

I chose a test "Voltage leves" which gave a response. So I think the USB interface is working. After that I uploaded the newest firmware and tried to contact the gateway with a small bash script from another post:

Code: Select all

stty -F /dev/ttyUSB0 9600 -icrnl -echo clocal
exec 3<> /dev/ttyUSB0
echo -e 'MM=10\r' >&3
read -t 1 response <&3
echo "$response"
exec 3>&-
I got a response from this script:
MM: 10

I expect this is the expected response... I am running otmonitor while this script is running. In otmonitor I can't see anything. Is this expected? Or am I missing something.

My setup (maybe it has to do with any of the components):
Boiler: Remeha Avanta CW4
Thermostat: Honeywell Chronotherm IV (on/off)
Gateway connected to a raspberry running raspbian.
hvxl
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Re: No answer from OTGW USB interface

Post by hvxl »

Don't access a serial device with two programs at the same time. It's a gamble which one gets the response. It's even possible that one gets a few characters and the other gets the rest.

What do you mean with: "In otmonitor I can't see anything"? You didn't see anything related to your MM test, or nothing at all? You managed to load the latest firmware, so communications must be working pretty well. Then you should also see opentherm messages, unless you gave a PS=1 command.

You may also send serial commands with otmonitor via Options -> Miscellaneous. That's probably easier than the bash script. You should then see the results in the log tab. And yes, MM: 10 is the expected response for a MM=10 command.
Schelte
breem
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Re: No answer from OTGW USB interface

Post by breem »

Thanks for your quick response again!

This morning I woke up and it was pretty cold in our home... The thermostat was showing the "heating" icon, but the boiler wasn't burning. So the gateway was somehow preventing the boiler from heating the house. To heat the house I took the gateway out and linked the wires of the thermostat directly to the boiler. Because I used the same wires as I was using to connect to the gateway (I connected them together inside the gateway) I ruled out bad wires or something like that.

I did give a PS=1 command with my bash script somewhere, no response to that as well, not in otmonitor nor as response to the bash script. So if that message causes me to miss the responses in otmonitor, it can explain a lot. The MM=10 command should turn the boiler on is it not?

I'll try connecting the boiler and thermostat to the gateway again and this time only use otmonitor to send/receive data. I'll post the results after the test.
hvxl
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Re: No answer from OTGW USB interface

Post by hvxl »

No, MM=10 doesn't turn the boiler on. It only limits the power to 10% when the thermostat turns it on. That was probably not sufficient to get the house up to the correct temperature before you woke up this morning. Some boilers can't even handle such a low setting and won't do anything at all.
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breem
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Re: No answer from OTGW USB interface

Post by breem »

Hi,

Good News! I reconnected the boiler and the thermostat again and I see data now in otmonitor. I don't know if I have changed something. Only possible change can be that I reconnected the wires from the boiler and or thermostat to the gateway the other way around.

Anyway, thanks for your help! Now its on to getting the boiler to start when I want from my own homeautomation project.
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