ZIMO MXULFA Decoder Update Module Tips & Tricks
Last Updated 250316 - Page Under Construction
Note: The MXULFA is shipped with 1x terminal block, 1x SUSI Cable, and 1x USB2.0 thumb drive only. Power supply is not included.
Decoder Update Device MXULF
English Version
MXULF Tutorials 5-part explanatory video on YouTube
- First steps MXULF: Installation and configuration tutorial part 1
- MXULF: Decoder sound load over track tutorial part 2
- MXULF: Decoder sound load over SUSI tutorial part 3
- MXULF: Decoder-software update with a PC part 4
- MXULF and its functions with a USB part 5
German Version
MXULF tutorials 5-part explanatory video on YouTube
Note: This video still refers to an MX decoder. When updating an MS decoder, connect the MX/MS tap only with a SUSI or track cable .
Additional help from ZIMO expert Mr. Paul Chetter, a.k.a. pauliebanger.
ZIMO MXULF First Release Version
Decoder Update Device MXULF
MXULF - The device
The ZIMO MXULF ( MX U pdate L aden F ahren) is more than just a simple decoder update device. Like a small digital system, it can perform the following tasks:
- Loading new software versions (software updates) from a USB stick into all types of ZIMO decoders (sound, non-sound, function, and accessory decoders); the vehicle is located on the "update track" with the decoder.
- Synchronous update for ZIMO accessory decoders of the MX820, MX821 generation installed in the layout
- Loading sound projects from USB stick into ZIMO sound decoder, vehicle on the "update track"
- Fast sound loading (approx. 2 - 3 min instead of 20 - 30 min) via the decoder's SUSI interface
- Parallel sound loading of multiple decoders via SUSI interfaces
- Driving operation & functions-switching for one address at a time via the controls of the MXULF (scroll wheel, 4 buttons, LEDs) to test the vehicle being processed
- Programming and reading the CVs of the connected decoder or vehicle
- Entering and checking the loading code (CV #260, ...) for coded sound projects
All of the above tasks can also be controlled from the computer; in this case, no USB stick is used; instead, all data (software update files, sound projects) are transferred via the USB interface (client). Programs such as ZSP (ZIMO), ZCS (Manhart), PfuSch (Sperrer), and others are used on the computer.
The previously offered version of the MXULF without a display is largely identical in terms of hardware, except for the missing screen, and, with the latest update, can still be operated today—especially when controlled via a computer. The later, current model with a display was therefore known for a long time as the MXULF A.
Today, the device is generally referred to as MXULF again, as it has always been on the casing, in the software, and in use by most users.
The MXULF can be used as a low-cost workshop system, and in many aspects it is even applicable to third-party decoders (of course not regarding software updates and sound loading).
MXULF control and display elements: 4 buttons, 1 scroll wheel, and 8 bi-color LEDs.
External connections: screw terminals for power supply, track (update track), "SUSI" connector, USB (client, to computer), USB (host)
The MXULF and the connected vehicle are powered by any voltage source (DC 12-20 V, AC 10-16 V). Therefore, a power supply is not included as standard, but is available as an accessory if required.
MXULF in decoder update and sound loading mode
Software update and sound loading with MXULF (for MX decoders and MS and MN decoders from SW version 4.08, full description see MXULF operating instructions )
IMPORTANT: Update MXULF beforehand by self-updating:
- Download the new MXULF software from ..UpdateMXULF as a .zip file, unpack the .zip file , save the two actual update files MXULF.ulf and MXULF.bin (names might be slightly different) in the root directory of a USB stick (ZIMO stick or other stick - most work ...).
- Preparing the MXULF:
- Disconnect all connections, reconnect “Power” (to the supplied power supply or track output of a digital command station) âžœ LED “Power” – green .
- Insert the USB stick prepared above ➜ LED 3 flashes red-green-yellow (if the correct files, i.e. .ulf and .bin, were found on the USB stick).
- Start self-update with button 3 (long, approx. 3 sec).
- Wait for the message “SELF-UPDATE OK” - “CRC OK” may appear instead!
- Unplug the USB stick and disconnect from “Power”.
- Reconnect “Power” âžœ MXULF ready for use.
Possible update and loading processes
There are different ways of updating or loading sounds for MX, MS and MN decoders:
- A USB stick or a computer can serve as the data source for the MXULF
- Loading from the MXULF into the decoder can then be done via rail or SUSI pins
- The "rail" method also applies to decoders that are plugged into a test board (MSTAP, MXTAP), which is connected to the MXULF via the "rail" connection
ATTENTION : Updating and loading sounds from the computer via rail is (as of 10/2023) ONLY possible with MX decoders!
Software update for decoders via USB stick over the rail (decoder installed in locomotive or test board)
- Download the new decoder SW collection file - .zsu file (if for MS decoder from ..MS-MN-Decoder-SW-Update ) and save it in the root directory of a USB stick ; preferably (easier) only this one .zsu file on the stick *)
- Connect “Power” (power supply or ...) to the MXULF âžœ “Power” LED green.
- Connect the rail (or connect the TAP to the "rail") , put the vehicle on the track (only vehicle on the track) ➜ LED "rail" yellow.
- Insert the prepared USB stick âžœ LED “1” yellow (if decoder SW collection file found), name of the decoder SW collection file on the display.
- Start decoder update with button 1 ➜ progress indicator on the display.
- Waiting for message “100%”
- Remove the vehicle from the track (or disconnect the decoder from the TAP) and, if further loading or update processes are to be initiated:
- Confirm with button 1 , then
- - if the sound project is on the same USB stick, i.e. âžœ LED “2” yellow , start loading the sound with button 2 (as below), or
- - put a new vehicle on the track (or connect the decoder to the TAP) for an update with the identical SW version.
Sound loading via USB stick via the track (decoder on test board or built into locomotive)
- Download the desired sound project - .zpp file from the ZIMO Sound Database and save it in the root directory of a USB stick * )
- Connect “Power” (power supply or ...) to the MXULF âžœ “Power” LED green.
- Connect the track , put the vehicle on the track, or plug the decoder into the MSTAP or connect the decoder cable âžœ LED “Rail” yellow .
- Insert the prepared USB stick âžœ LED “2” yellow (if sound project/zpp found), name of the sound project on the display.
- Start sound loading with button 2 ➜ progress indicator on the display.
- Waiting for the message “SOUND 100%”
- De-rail the vehicle or disconnect the decoder from the TAP , and, if further loading or update processes are to be initiated:
- Confirm with key R , then ready for operation again
*) If there are multiple .zsu and/or .zpp files on the stick, the first two files will be displayed, and others can be made visible by scrolling. The file marked with an arrow is then ready to be loaded into the decoder (press the T or R key).
Sound loading via USB stick via the SUSI pins (decoder outside the locomotive)
NOTE: SUSI loading is the faster alternative (approx. 10x), but only possible if the decoder is NOT installed. This requires the connectors (PluX, MTC, Next18, etc.) on an MXTAP or MSTAP test and connection board . With wired decoders (including NEM-651 or -652), sound loading via the SUSI pins is also possible, but the SUSI connectors (solder pads are provided) must be made accessible by soldering wires (this will void the warranty!).
- Save the desired sound project to a USB stick * )
- Connect the decoder to a suitable interface (PluX, MTC, Next18,...) - for safety reasons, with the connection board switched off (on/off switch on the board).
- Connect “Power” to the MXULF âžœ “Power” LED green.
- Connect the connection board (MXTAP or MSTAP) to the MXULF using a SUSI cable (connectors "SUSI").
- Press the R button (long, approx. 3 seconds) ➜ Opens the MXULF menu on the display.
- Use the scroll wheel to select “ SUSI SOUND Load ”.
- Press R key (short) ➜ Start sound loading, progress indicator on the display
- Waiting for message “SUSI 100%”
- Confirm with key R , then ready for operation again
*) If there are multiple .zsu and/or .zpp files on the stick, the first two files will be displayed, and others can be made visible by scrolling. The file marked with an arrow is then ready to be loaded into the decoder (press the T or R key)
Using the MXULF from the computer:
The USB interface (client, left) of the MXULF can be used for two different tasks:
- Decoder software update and sound loading with the ZSP software.The update process and sound loading and the functionality of the ZSP can be found in the current ZSP manual ;
software updates are available under ZSP-ZIMO-Sound-Programmer.CAUTION: Update and sound loading from the computer via rail is NOT possible (as of 10/2023) with MS and MN decoders. - Configuring (CV programming and reading), as well as driving - from the computervia the so-called "binary protocol" and with the ZCS software. Information and a download link can be found under ZCS - ZIMO-CV-Setting .
NOTE: Original Source Last update: March 28, 2024 (used with permission) https://www.zimo.at/web2010/products/MXULF-Decoder-Updater.htm
Software Updates for MS Sound Decoders & MN Non-Sound Decoders
Decoder SW update
ZIMO decoders are continually being improved. New features are added, functionality is improved, and bugs are eliminated. Therefore, it is advisable to equip MS and MN decoders with the latest software (SW). MN non-sound decoders operate with the same software as their underlying MS sound decoders. The SW version of a decoder can be read using CV #7 (main version number, value 3 or 4) and CV #65 (subversion number).An MS or MN decoder update proceeds as follows:
- Update of the MXULF: Info under Decoder Update Device MXULF
- Always use an up-to-date MXULF software for the best results.
- Download the software update file (see below): then unzip the zip file and load it onto a USB stick (formatted with FAT32).This "collection file"contains the latest software versions for all ZIMO MS and MN decoders.
- Loading the update software via MXULF: Connect the USB stick containing the update file and the decoder to the MXULF/A. The update starts by pressing the "T1" button (LED 1 lights up) and ends when "100%" is visible on the display (next to the decoder and software versions). The USB stick can now be removed.
- USB stick: the sound project is saved as a .zpp file on the USB stick (in the root), and loaded via the MXULF menu item “SUSI Sound Load”.
- ZSP via USB cable: In the ZSP menu, check the "Decoder / Project programming via SUSI on/off" option and then click the "Decoder / Project (Sound and CVs)" option. SUSI sound loading is also possible via ZPP Config.
- For details, see the MXULF and ZSP manuals.
Starting with MS Decoder software version 4.14, it's possible to load sound projects via the "rail" connection. This can currently only be done from a USB stick (not from the ZSP via a USB cable).After inserting the USB stick into the MXULF, LED 2 lights up. Pressing button 2 loads the sound project into the MS decoder. A SUSI connection between the MXULF and the MXTAPV should be avoided in this case.THE MOST IMPORTANT STEPS & INFORMATION
1.MXULF UPDATE More infoA decoder software update (and loading a sound project) usually requires the latest version of the MXULF software , which needs to be updated regularly due to the rapidly growing number of MS and MN decoder types.Therefore, please always make sure to update your MXULF with the latest software before (!) performing decoder updates.Note: The previously offered version of the MXULF without a display is largely identical in terms of hardware, except for the missing screen, and, with the latest update, can still be operated today—especially when controlled via a computer. The later developed, current model with a display was therefore known for a long time as the MXULF A. Today, the device is generally referred to as MXULF again, as it has always been on the case, in the software, and in use by most users.
- first UPDATE BOOTLOADER
- Download the BL update file (right) and unzip the zip file.
You'll then find individual .zsu files for your decoder in the zsu folder. - Affected are the decoder types/families MS440C, MS450, MS480, MS490, MS580, MS590, MS990
- Update your decoder with this bootloader update on a USB stick using the MXULF on the track cable as follows:
Press the "R" key for approximately 3 seconds to enter the MXULF menu and scroll to the "MS SW Power Cycle" entry. If there are multiple update files on the USB stick, select the appropriate file for the connected decoder using the scroll wheel. Pressing the "R" key starts the Power Cycle update. It is completed when "...100%" appears on the MXULF display.
- Download the BL update file (right) and unzip the zip file.
- then update to the latest decoder software
- Now update the decoder to the latest software version, which you can download below.
- MN non-sound decoders
can only be updated starting with software version 4.229 . When attempting to load previous software versions for MS sound decoders, MN non-sound decoders are ignored by the MXULF. - MS450:
If an MS450 with software version between 4.14 and 4.92 is no longer responsive after the update , it can be made operational again by installing the MS450-specific software version using a "Power Cycle Update" (see next note) in the MXULF. You can find this in the archive section on the far right in the line for the corresponding software version (e.g., "MS450_4_92.zip" for version 4.92). - MS450
If an MS450 has a software version older than 4.08 (or the update method described above doesn't work; max. up to version 4.107), the update must be performed using the decoder-specific software "MS450_4_xx.zsu" (only for MS450, see archive below) and using the "Power Cycle Update": Press the "R" key for approximately 3 seconds to enter the MXULF menu, then scroll to the "MS SW PowCycle" entry. Pressing the "R" key starts the Power Cycle Update and completes it when "...100%" appears on the MXULF display.
MS Decoder Application Notes

- Software update from USB stick (SW collection file) via tracks.
- Sound project loading from USB stick via track.… also via SUSI.
- Sound project loading directly from Computer (ZSP) via SUSI.
- The index pin of the MTC plug on the MXTAP is cut off, but the "stub" can pierce the solder lacquer on the MS440, contact a conductor track (on MX decoders MX644 none at this point) and destroy a diode (do not press it firmly for safety)
- The function outputs starting from FO3 now occupy different pins due to adaptation to the valid NMRA standard; therefore display LEDs or designations do not match
- The pin assignment of the MS large scale decoder is similar, but not completely identical to MX. Thus, an MSTAPK2 is offered though, but it only contains the connectors for the "small" MS decoders, not for large scale decoders; for latter an MSTAPG is also available.
"SW version not permissible" Error
SBS4DCC Customer Inquiry
My installer (Alex at DCCTrain) has downloaded the following (free) 16 bit sound file into the decoder: "BR 50 / Br 03.10 / BR 78 / BR 211".
However, my installer is not able to update the firmware in the decoder. When attempting to update the firmware in the decoder, the MXULF is displaying the following error message "SW version not permissible".
The following (very short) video (of my installer attempting to install the firmware update on my MS990) demonstrates the problem.
https://youtu.be/ejwQel1gmDA?si=uEnN3QqJXuCfpA2o
SBS4DCC Response
Read through all of the notes on this page. The second note has a download file and instructions for a bootloader update.
https://www.zimo.at/web2010/support/MS-MN-Decoder-SW-Update.htm
I have done this many times now. Just follow the directions and you should have no problems. Maybe once or twice I had to install the update twice before I could get the new firmware to load.
High Speed Loading via SUSI
Software Updates for MS Sound Decoders & MN Non-Sound Decoders
Software Updates for MS Sound Decoders & MN Non-Sound Decoders