Port Doubler & I2c

  • Platform information:
    • Hardware: _CPUArchitecture/RAM/storage_Raspi 3B
    • OS: _what OS is used and which version_openhabian 3.1.0
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    I want to use a Port Doubler for my Raspi to control my Rollershutters. For this i need more GPIO’s. I also need the I2C Bus to connect the A/D Converters for Temperature and other Parameters. Now i want to buy this Port Doublers: JOY-IT RB-Port-Doubler online kaufen | Pollin.de
    Can i use the I2C Bus when this Bord is connected?
    A/D Converter: JOY-IT RPI Analog/Digitalwandler | Pollin.de

Hi Martin,

your questions are not exactly OH questions, a RasPi or electronics forum might be better suited :wink:

To answer your port doubler question: Do you need more physical contacts? Then yes, you may use this device. BUT if you intend to increase the locical I/O ports the RasPi offers, you will need another solution. There is an explicit warning about that on page 4 in one of the documents linked on the distributors site.

As for your converter question: properly connected it should give you 4 analogue ports. But I did not find information about the scan rate (number of measurements per time period). I expect it should be fast enough for temperature measurements. As I do not know what your “other parameters” entail, you may want to check that or ask a search engine for examples and experience other users made using it.

OK excuse me, i’ll look at other forums for hardwareproblems. But thank you for reading the datasheet of the port doubler. I didn’t see that it’s really only a port doubler. At the moment i’m looking for the right hardware to realize my rollershutter management, and maby more.
The ADC is a Texas Instruments ADS1115, 16Bit, 860 SPS. I found the datasheet in the web.
Now i have to search a port multiplexer. I need 24 I/O pins/ floor and raspi. All the wires of rollershutter and sensors are ending in 2 distribution-racks.
Please tell me if you know a any GPIO Extender for my problem.
I think i found some :slight_smile:

The link seems to point to your personal basket, not a single product: I’m asked for login credentials.

Oh, sorry. I hope now it works. 5pcs MCP23017 Serial Interface I2C Bidirectional 16-Bit I/O

From what you told us and the description it should do the job. But I want to point out that I have no experience with it. Hence: