Navigator DFE r6.0 and later has a transport layer for the purpose of starting and stopping a paper path or a paper feeder or some other device.  Navigator DFE uses the "transport layer" for starting things you may wish to start at the same time as the printhead is uncapped.  This "transport layer" recognizes when a DuraFlex printhead is uncapped and the buffers are ready to print.  It can send on/off commands. The Navigator DFE transport layer supports 4 modes.  

Note: This transport layer is available for any printer.  Currently we support paper path, vacuum, dryer, and other accessory handling for HP FI-1000, DuraFlex, and DuraBolt.  Other printers can take advantage of it as well.  If you are working on a project, please contact Xitron.

For HP FI-1000, you need to have the Xitron PCA card.  Go here for more details

For DuraBolt, contact Memjet.

For DuraFlex, read this document below.

0 = no transport.

1 = Informational only

2 = Numato-USB

3 = Modbus

Mode 0.  No transport.

Use this if you are controlling your paper feeder with manual controls or with software that is unrelated to Navigator.  This mode is ignorant of paper path considerations.

Mode 1.  Informational only.

In this mode we publish "Start Transport" and "Stop Transport" to the User Interface to give a hint to a manual press operator to start the paper feed.  This mode differs from mode 0 only in that it sends these messages to the UI.  

Mode 2.  Numato USB

Supports a 4 channel USB relay card (details on the card below) for the purpose of switching things on and off.  It was envisioned to enable printer manufacturers to turn on and off paper transport systems, such as conveyor belts or paper feeders.

We have two levels of support for this.

1.  a stand alone application which allows for manual toggling of the channels on the card.

2.  automated control from the Navigator DFE using the Navigator DFE "transport layer". 

In either case, the card has helpful LED lights to indicate when each switch is on.

Mode 3. Modbus protocol

Modbus is a common control protocol for PLC's.  If your device speaks Modbus then we may be able to drive it with this feature.  We have tested it with Lemorau/Schneider control cards.  The Modbus interface is configurable in an INI file.

Server configuration

The Server INI file can be configured to support any of the Modes.

The file is found at %appdata%/xitron/navigator

Under the [Duraflex] heading you can configure Navigator to use your preferred mode.

Media transport communication type.

Valid values are:

0 = no transport.

1 = Informational only.

2 = Numato-USB.

3 = Modbus


If using modbus specify the type of support for the PLC.  Type 1 is for paper path only.  Type 2 brings in more control but it is currently not finished and unsupported.  Use Type 1.  An example of a tested working PLC speaking Modbus with this system: Lemorau/Schneider.

1 = paper path start/stop commands.

2 = <Future Expansion>


For Modbus the IP address for the media transport

(PLC Modbus server address for Lemorau board.)


Port to be used by the Modbus transport comms.

This should generally be 502.  


in the case of multiple modbus compatible devices on the network you may need to tell us 

which "slave ID" your desired device is using.


How long to wait for signal indicating machine is ready for us to start the transport.

Applicable to Modbus only.


NumatoUSBRelays identifies which relay(s) to control.

The relay identifiers are bits. Use Bit 1 to turn on Relay 1. Add bits together to get more than one relay enabled.

; Turn on and off Relay 1:  NumatoUSBRelays = 1

; Turn on and off Relay 2:  NumatoUSBRelays = 2

; Turn on and off Relay 3:  NumatoUSBRelays = 4

; Turn on and off Relay 4:  NumatoUSBRelays = 8

; Turn on and off Relay 1&2:  NumatoUSBRelays = 3

; Turn on and off Relay 1&3:  NumatoUSBRelays = 5

; Turn on and off Relay 1&4:  NumatoUSBRelays = 9

; Turn on and off Relay 1,2,&3:  NumatoUSBRelays = 7 

; Turn on and off Relay 1,2,3,&4:  NumatoUSBRelays = 15


Numato-USB comm port.  This will be the serial comm port the USB is associated with.

You can look in Windows Device Manager under "Ports" to find this out.


Example configuration setting for a Lemorau PLC using Modbus








Example configuration setting for a Numato USB relay card





Example configuration setting for no paper path awareness in Navigator at all



Example configuration setting for no physical paper path control but with the awareness of when a press operator should start and stop the feeder; providing User Interface feedback at the right time.



Getting the Numato USB system running for the first time

RelayController.exe needs to be installed on a computer that already has Navigator installed on it. 

The path location of your installation for RelayController is not important.  You can put it where you want as long as it can find Navigator.  Upon the occasion of the first run of the application it will ask you to show it the path to Navigator Server.  It will be something like c:/navigator/navigator usually.

If the software asks you for a port number for your card; enter it.  

 If you don't know it, check Windows Device Manager.  In this case, the correct entry is "3".

Subsequent uses of the application will pop this dialog box up at start up time.  If there is already an number entry you can just dismiss the dialog by hitting <enter> or clicking OK.


Upon running the application for the first time it may ask for the path to your Navigator installation.

This is usually c:/Navigator/Navigator.  You may have chosen a different path.

After these initial dialog boxes are dismissed, "RelayController.exe" will show the window below.  The toggles represent each of the 4 channels on the card.  Toggling them on and off will open and close the relays.  LED lights on the card will show this happening.


Perhaps you wish to change the name of the application's main window to more closely reflect your actual purpose.  It could reduce confusion during a development phase.  Click the gear button on the main window.  It brings up configuration options.

Now I get this:

What if you aren't planning on using 4 channels?  Clicking the configuration button (a gear) brings up this window below.  You can see my serial port ID is 3 (which we found from looking in Windows Device Manager and noticing that it was at the port COM3).  You can also choose to limit your channels to a smaller number.

I'll switch to 1 channel.

Now the main application window looks like this:

When the application window looks like the above (with the first relay switched on) the card looks like this:

When the application window looks like this (channels A and C switched on),

The card looks like this:

You may wish to change the logo to your own company.  You may wish it to be a picture of the mechanism you are switching on and off.   Whatever you prefer, it just needs to be a PNG file.  Change it by following along below.

Then you will get this:

This manual control application and the cards are available now (May 2021).   DuraFlex and other printers can be used with the manual application now.  Automated use is planned for DuraFlex only at this time.   Other printers will be supported for automated use in the DFE upon customer request.

Update (February 2022)  DuraFlex DFE r6.0 and later support automatic start and stop of a paper path via either Modbus or the USB relay card.

Appendix A.  Relay card details.

  • 4 onboard Solid State Relays with individual LEDs for status.
  • 3A Maximum Switching Current.
  • 4 TTL (3.3V)Compatible GPIOs.
  • 4 Analog Input Channels (Multiplexed with GPIOs) with 10-Bit Resolution.
  • USB interface with CDC support. 
  • Can be powered from USB or external power supply.
  • Requires a USB to USB mini cable

Appendix B.  Troubleshooting.

If you do not get correct results from the application:

-   Check that your port is correct.  If you have the port set to the wrong number (or not set at all), the application will not properly initialize.  If you cannot get the app to boot, you have a problem with the connection to the card.  

-  Check that the device shows up in Device Manager.  If not, check your cable connection.

-  Check that the board has power.  There is a small red light directly on the board, near the USB port.  When the board is getting power, this light is on.


Appendix C.  Safety.

Do not turn on heaters or dryers with this.  

Such devices require safety trips so that you cannot accidentally leave them on.  This tool is for turning things on and off that don't have the potential for disaster.  If you have a separate safety trip (e.g. something that detects temperature or movement which also must be satisfied or the connection breaks and the device turns off), then you could consider using this tool as a simple on/off.  But it would only be a part of your solution.  Using only a simple on/off tool such as this to control a dryer or heater would be a bad idea and is not supported by Xitron.  It could function as part of a system that must be satisfied by multiple conditions.