Expansion port connector extended pinout?

Dear all,

I need to understand the pin functions of the 14-pihead-connector of the IND.I/O module.
Because of I need a free pin for digital I/O which I can control via Arduino sketch in the usually way ("pinMode(pin, OUTPUT);... "digitalRead(pin);").
This is important to do so (and not over the regulary 24V-Inputs).
So, I designed a table to replace the "?" against the functionality.

Expansion port ( IND.I/O ):                                           Ethernet expansion module:                                                        Arduino-sketch:
connector pin #     pin name     special pin function     needed for     Pin necessary?    W5500     SD-Card     FRAM     pin # (in sketch)
1                            D14             MISO                          SPI                 YES                     YES          YES           YES         ?
2                            -                  +V5                              -                     YES                     YES          YES           YES         -
3                            D15             SCLK                          SPI                 YES                     YES          YES           YES         ?
4                            D16             MOSI                          SPI                 YES                     YES          YES           YES         ?
5                            D10/A10      ?                                 ?                     ?                          ?               ?                ?              ?
6                            -                  GND (ISO2)                -                      YES                     YES          YES           YES         -
7                            D4/A6          ?                                 ?                     ?                          ?               ?                ?              ?
8                            D5               PWM                          ?                      ?                          ?               ?                ?              ?
9                            D7               ?                                 ?                      ?                          ?               ?                ?              ?
10                          D6/A7         ?                                  ?                     ?                          ?               ?                ?              ?
11                          D0               RX                               Serial?           ?                          ?               ?                ?              ?
12                          D1               TX                               Serial?            ?                          ?               ?                ?              ?
13                          D2               SDA                            I²C                   ?                         ?               ?                ?               ?
14                          D3               SCL                            I²C                   ?                          ?              ?                 ?              ?

Please helped me to understand it because of the documentation about that is not clear for me.

Also, I believe there are more people interested about this!

Thanx a lot.
Best regards,

Jack M.
Jack M.
| 2 1 1
Asked on 5/20/16, 2:33 PM

Hello Jack,

depending on your hardware setup and your sketch, all these pins can be used as digital I/O or analog input where specified and these are just pin coming straight from the MCU.

So you can take any of these, unless you are using it for another function, like ethernet or SD.

Please note that RX and TX in both arduino platform are not connected to the USB connection. These pins respond to Serial1 and not to Serial, so if you do not need an additional Serial and you don't use RS485 interface, which I guess is controlled by these pins, you can use them.

D2 and D3 are also available if you don't have any I2C peripheral.

Ethernet will need a CS signal and SD another one. You can easily find what these are in the example sketches.

The 24V I/O has the same numbering but is provided by external hardware through the Indio library, so digital pin 1 of Indio is different from digital pin 1 of the MCU.

I don't know if I centered your question, maybe you can be more specific with a practical code example.

Stefano Giuseppe Bonvini
Stefano Giuseppe Bonvini
| 2 0 2
Answered on 5/20/16, 8:41 PM

Thank you for answering Stefano,

This approve my assumption.
So, in my application (1286-Topboard, IND.I/O, Ethernet-Expansion module), I will need all the features of the ethernet module (Network, SD-Card, FRAM).
Also, I need the I²C-Bus (from expansion port) to controll a lot of I²C-I/O-modules!
Those I²C modules have a common open-collector-output called "INT" (parallel connected) to flag a change event.

In one of the ethernet example codes, i saw that 3 pins will declared as an output and setted to high.
May, these are the chip select pins for W5500, SD-Card and FRAM (pin-#: D4, D6, D10).

Furter questions:
1.) Which of those 3 chip-sellect pins are for which part of the module?
2.) Means the "high"-status an activation?
3.) By useing all the functionality (above described), the following pins are bussy:
D14/MISO, D15/SCLK, D16/MOSI, D10/CS-Pin, D4/CS-pin, D6/CS-pin, D3/SCL, D2/SDA ?!
This effects that the free (for another things) pins are:
D5/PWM, D7, D1/TX, D0/RX.
Is this correct or is the ethernet expansion module useing one of them also for another things?

Thank you so much.

Best regards,

Jack M.
Jack M.
| 2 1 1
Answered on 5/22/16, 6:21 AM

1) check ethernet schematics https://static.industruino.com/downloads/schematics/IndustruinoEthernet.pdf 2) usually LOW 3) it should be correct. You can use one of them for your INT pin, check which one has an interrupt capability on 1286 MCU. Probably all of them!

Stefano Giuseppe Bonvini
on 5/22/16, 8:57 AM

Thank you again! It works fine. ;)

Jack M.
on 5/27/16, 6:45 AM

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Asked: 5/20/16, 2:33 PM
Seen: 3371 times
Last updated: 5/22/16, 6:21 AM