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RevolutionPi IO-Modules FAQ

Owned by Dirk Conzelmann
Last updated: 24.Jul 2024
7 min read

Can I…/What can I do…?

I want to run a RevPi RO module, but I can't configure it in PiCtory, what am I doing wrong?

  • The RevPi RO module is only supported as of RevPi OS Bullseye. Please update your system as follows:

https://kunbus-gmbh.atlassian.net/wiki/spaces/KS/pages/836468748

I would like to use a counter at the input of a DIO module. Is it possible that the module counts down?

Check if you have forgotten to activate debouncing. You can do this in PiCtory with the setting "InputDebounce".

Would it be possible to write in Input registers (Holding registers) of Virtual Modbus TCP server?

Yes, take a look at the tutorial How to Use RevPi Core as Modbus TCP Master.
The Function Code "READ_HOLDING_REGISTERS" is implemented (Read a whole 16-bit input/output register).

https://revolutionpi.de/forum/viewtopic.php?f=6&t=2651#p9744

What is mean by this cryptic error description of the DIO Module - Bit 7: Error prompt of the input IC?

This status originates from the 8 Bit Diagnostic Truth Table on p. 20 in the MAX14900E data sheet.

Thus, the error can be triggered by "overload", "open load" or "under voltage".

What is the advantage over a Modular Gateway and a Revolution Pi Connect module? Both devices have Ethernet interfaces – so why should I buy separate hardware?

https://revolutionpi.de/forum/viewtopic.php?f=6&t=2747#p9978

Which part to buy to communicate with MODBUS RTU over SERIAL.

It is recommended using the Modbus RTU Gateway and configuring it as RS232 or RS485 (or RS422). This is much easier to configure than the Serial Gateway.

If you have a Revolution Pi Connect +/SE/S/4, you can use the front interface as RS485.

Revolution Pi Connect RS485.png (82.96 KiB) Viewed 295 times

If you have a Revolution Pi Core 3/3+/SE/S/4, you can use one of the front USB ports and configure it as a virtual Modbus RTU Master/Slave (RS232/RS485).

Additional Information:
Modular Gateway
Gateway module for serial network
Gateway module for Modbus RTU
Revolution Pi Gateway Tutorial

My Pi Bridge freezes with the classical error in kernel logs: "too many communication errors → set inputs to default". What can I do?

Update the firmware of the modules.

https://revolutionpi.com/tutorials/images/firmware-update/

The output of the DIO module behaves strangely, what can I do?

Please perform a firmware update of the DIO Module. There were changes in firmware version 1.5. Which affects the timeout behavior.

https://revolutionpi.com/tutorials/images/firmware-update/

What can I do, when DIO module with PNP Sensor not giving Data?

If your power supply on X4 is really 24V and after setting 02 to 1 (piTest -w O1,1) and getting 11V, The first interpretation would be that you are using the wrong ground. The X2 supply on top of the RevPi is the one that supplies the inputs and outputs. So make sure you use the ground for this supply and not the ground at the bottom for the X4 supply, which is exclusively for the CPU supply. Another reason would be that your RevPi DIO is defective.

I have an AIO module and I want to make an RDT measurement with a PT-1000 resistor. The problem is, but the readings do not change. What can I do?

Please follow the link below : RTD-Messung erkennt PT-1000 nicht - Revolution Pi Forum

Turning on outputs of DO module via Node-Red does not work. When we set the pins to 1 (via shell and via Node-RED) we get no signal on the pins. What can be done?

Please update PiCtory Version 2.0.6 and for more details look at this link: DO Module - Ausgänge schalten nicht - Revolution Pi Forum

I am using Node-RED. Strangely, accessing values from the process image does not always work. What can I do?

On the RevPi Connect, you can use the Watchdog Timer to restart your device and application.

https://revolutionpi.de/forum/viewtopic.php?f=3&t=3073

What is the difference between the RevPi AIO module and RevPi MIO module?

In the link below, you will find the Data Sheets of the AIO and MIO modules. So all the info that you are looking for, will be there: https://revolutionpi.com/tutorials/down ... enblaetter

I want to put an EtherCAT network into operation together with a DIO module and I have problems, what can I do?

https://revolutionpi.de/forum/viewtopic.php?f=6&t=1413&p=5523#p5523

Revolution Pi Gateway Tutorial

After connecting the DIO module to a RevPi module, the power LED flashes red. What to do there?

I have a Revolution Pi DIO module, as soon as I remove the 24V supply (X2) on the inputs, all inputs are switched to ON (1), what can I do?

If the power supply on x2 is removed, all Inputs are set to 1.


This can be viewed in the “status” WORD.

The status bits are explained in the following introduction.

Bit 7: Error prompt of the input IC

https://revolutionpi.de/tutorials/ubersicht-revpi-i-o-module/konfiguration-dio-di-do/

piTest -1 -r Status,b

Unfortunately, you can't change this behavior.

How to …?

How is the I/O data exchanged between Revolution Pi and IO modules?

In Little Endian format.

https://revolutionpi.com/tutorials/video-tutorials/?noredirect=en_US#VT12

How to wire the Revolution Pi AIO, MIO, DIO, DI, DO modules?

The following picture shows how to wire the modules to the electrical circuit.

The modules cannot be operated stand-alone. A RevPi Core (3 | 3+ | S | SE | 4), Connect (+ | S | SE | 4) is required.

You can find and Download the Datasheets, Schematic and other information in the link below:
https://revolutionpi.com/tutorials/downloads/?noredirect=en_US

And Video Tutorials:
https://revolutionpi.com/tutorials/video-tutorials/

How can I connect 2 a wire active sensor with 4-20 mA signal to a RevPi AIO module?

RevPi AIO module is suitable For passive 2, 3 (this version isn't shown) and 4 wires ; but not for active RTD sensors! . For how I can connect an analogue sensor to the RevPi AIO module, see here: https://revolutionpi.de/forum/viewtopic.php?t=3407

How much RevPi IO Modules can I connect to a RevPi

Module

Left side

Right Side

Module

Left side

Right Side

  • RevPi Core

  • RevPi Core 3

  • RevPi Core 3+

  • RevPi Core S

  • RevPi Connect

  • RevPi Connect+

  • RevPi Connect S

  • Typically, 1 Con Module

  • Ii.e. RevPi Con CAN

  • Amount depends on the used pins of the Con Bridge

  • RevPi Core SE

  • 5 IO Modules

  • No RevPi Gateway Support

  • 5 IO Modules

  • No RevPi Gateway Support

  • RevPi Connect SE

  • 5 IO Modules

  • No RevPi Gateway Support

  • Typically, 1 Con Module

  • Ii.e. RevPi Con CAN

  • Amount depends on the used pins of the Con Bridge

RevPi Connect 4

  • 5 IO Modules

  • 5 IO Modules

How can I use the high-side or push-pull mode of the Revolution Pi DIO?

Yes, you can find the application notes about the high-side and push-pull modes in the following links

Commissioning RevPi DIO | DI | DO

Is there …?

Is there a detail configuration for the scaling of the AIO input/output values?

https://revolutionpi.com/forum/viewtopic.php?t=4042

Is there a code for how can I control the module or the ports of the AIO with Python?

Yes, here is an example for BitMirror:

https://revolutionpi.de/forum/viewtopic.php?f=6&t=2535&p=9196&hilit=bitmirror#p9196

Revolution Pi Python Introduction

Would it be possible to configure an AIO to output voltage depending on boolean message?

Check out our forum: https://revolutionpi.de/forum/viewtopic.php?t=3487

Is there an example of how I can connect an analog sensor to the RevPi AIO module?

Yes, we have an example in our forum. You can find this post at the link below.
https://revolutionpi.de/forum/viewtopic.php?t=3407

Is it possible to make a simulation of DIO?

Yes, see here: https://revolutionpi.de/forum/viewtopic.php?f=41&t=2080

Is there a possibility to establish a LIN bus communication with your Revolution Pi or are there extension modules that can do this?

We do not offer a LIN extension module or generally a solution for using the LIN bus.

Is there a module-wide limit in the DIO that reduces the specified maximum output current of a particular port under certain conditions?

All 14 output ports can supply 500mA simultaneously, in High-Side mode.
If the module gets too warm, all ports are switched off. This prevents the device from being damaged.

Is it possible with the AIO module to display temperature as negative C° values?

Since the 4 analog inputs share hardware on the AIO module, is there any statement on common mode voltage for the 4 inputs?

Yes, it is 45 Volts.

https://revolutionpi.de/forum/viewtopic.php?f=3&t=1641

Others Questions…?

What I want to know is on the Digital input what is classed as a 0 (Off) and what is classed as a 1 (On)

Take a look at the Link below:

https://revolutionpi.de/forum/viewtopic.php?t=960

I am using an AIO module and was wondering if I need to connect all the ground pins.

Yes, for more details: connecting GND pins for AIO module, how few can I get away with? - Revolution Pi Forum

Using a DO or DIO module, would it be possible to activate Hi-Side Switch and Push-Pull selectively for individual channels?

I want to use the RevPi MIO Module, but I can't find it in PiCtory, can this be?

We read that the RevPi can have up to 5 i/o modules, but in PiCtory we can configure 8 modules.

We support 5 extension modules for each side of the RevPi with a PiBridge connector.

You can configure more than 5 modules in PiCtory, but officially this is not supported!

Does the position of the modules influence the cycle time in a RevPi Core 3 device?

  • No, the position of the modules on the RevPi Core is independent of the cycle time.

  • All devices are polled one after the other.

In case of a voltage loss at the X2 connection of the Revolution Pi DIO, signal 1 is output at all inputs (I1 -I14). Is this behavior normal?

Depending on the observation, a reason can be found for a "0" or "1" in this specific case. The fact that the input supply voltage is missing can be recognized via the status bits 1 + 2, 4 + 5. A description can be found here:
https://revolutionpi.de/tutorials/ubersicht-revpi-i-o-module/konfiguration-dio-di-do/

If there is no input voltage at terminal X2, the status bits are all set.