Port Doubler & I2c

Setup, Configuration and Use Beginners
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  • Platform information:
    • Hardware: _CPUArchitecture/RAM/storage_Raspi 3B
    • OS: _what OS is used and which version_openhabian 3.1.0
    • Java Runtime Environment: which java platform is used and what version
    • openHAB version:
  • Issue of the topic: please be detailed explaining your issue
  • Please post configurations (if applicable):
    • Items configuration related to the issue
    • Sitemap configuration related to the issue
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  • If logs where generated please post these here using code fences:
    Hi
    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
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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.

3

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:
https://www.amazon.de/gp/huc/view.html?ie=UTF8&newItems=C133700fa-ca52-4abf-9e9f-4ae87fc2e9dc%2C1

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

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

6

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:

:wink: