Opentherm Gateway RS232 pin setting

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raymonvdm
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Opentherm Gateway RS232 pin setting

Post by raymonvdm »

Today i recieved the pic and would like to continue with the project. But i need to know which pins to connect to which pins on the SUB-D connector

On the schematic i found the following pins

Pin 3 = T1 out = RX on SUB-D = Pin 2
Pin 5 = R1 in = TX on SUB-D = Pin 3
Pin 9 = GND = GND on SUB-D = Pin 5

Is this correct ?
Running HS3PRO on PC with Z-Wave / OpenTherm / Plugwise / RFXcom / MQTT / XAP400 / Logitech Media Server and Squeezelite on PI`s
hvxl
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Re: Opentherm Gateway

Post by hvxl »

I chose the pin layout in such a way that the cable is easy to make. That means one row of pins goes to the top row of the DB9 connector and the other row of pins goes to the bottom row of the DB9 connector.

Graphically represented (ribbon cable on the left, DB9 on the right):

1 --------------- 1
2 --------------------- 6
3 --------------- 2
4 --------------------- 7
5 --------------- 3
6 --------------------- 8
7 --------------- 4
8 --------------------- 9
9 --------------- 5
10 -----

Of course many of these pins are not connected to anything, so they don't really need to be wired.
Schelte
raymonvdm
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Re: Opentherm Gateway

Post by raymonvdm »

For now i just used an PinHeader to comport unit which was common in the time of the 486 PC

Image

I also use 15 feet of utp (thanks Ziggo :D ) and two of these connector

Image

And at last

Image

I`m seem to be able to communicated with the gateway and using the HomeSeer plugin and the OTmonitor i can see data. However i cannot see the room temperature so it seems like my boiler or thermostat is doing something strange
Running HS3PRO on PC with Z-Wave / OpenTherm / Plugwise / RFXcom / MQTT / XAP400 / Logitech Media Server and Squeezelite on PI`s
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