sahin6033 - 2026-03-17

Hi,

I am trying to load a test application into a DSE M840-001-02 display, but after reboot the device still shows:

“No application loaded”

I would like to understand whether the problem is in my project, the package creation process, or firmware/runtime compatibility.

Hardware

Device: DSE M840-001-02

Firmware used: M840 MKII Firmware File v4.1.2

Software

CODESYS V3.5 SP12 (32-bit)

DSE CODESYS Package v1.5.44

DSEServiceTool

What I did

Created a new empty Standard Project

Selected target/template:

M840-02 V4.1

Used a minimal ST program only:

PROGRAM PLC_PRG
VAR
xAlive : BOOL := TRUE;
END_VAR

Confirmed:

project builds

PLC_PRG is assigned to MainTask

created Boot Application

Generated CodesysApp.pkg

Put the M840 into bootloader mode

Sent the package using DSEServiceTool

DSEServiceTool result

Transfer completes successfully and I get:

connection accepted

100% download

package ACK

<status>OK</status>
**
Example log:**

Searching for controllers....
sendPackageToController: waiting for incoming data connection...
sendPackageToController: connection accepted...
<status>Downloading</status>
<percent>20</percent>
<percent>40</percent>
<percent>90</percent>
<percent>100</percent>
sendPackageToController: sent 112cb8 bytes OK
Package ...\CodesysApp.pkg transferred to controller c0a80101 OK
sendPackageToController: package ACK
<status>OK</status>
Actual result

After reboot, the display still shows:

“No application loaded”

Additional issue I also saw earlier

At one stage I also had these fatal errors in CODESYS:

[FATAL ERROR] Unresolved reference: 'IOMGRLOCKENTER'
[FATAL ERROR] Unresolved reference: 'IOMGRLOCKLEAVE'

I checked library versions and adjusted them to:

IoDrvBase = 3.5.5.0

IoStandard = 3.5.10.0

Also, I am using CODESYS SP12, which I understand is the correct version for DSE M840.

My questions

If DSEServiceTool shows Status OK and package ACK, but the device still says “No application loaded”, does that mean:

the .pkg was transferred but not accepted as a valid application?

the package was built incorrectly?

the boot application / runtime / firmware versions are still mismatched?

What is the correct procedure to generate CodesysApp.pkg for M840-02 V4.1?

Is there any known compatibility issue between:

DSE CODESYS Package 1.5.44

M840 MKII Firmware 4.1.2

CODESYS 3.5 SP12

Has anyone successfully loaded even a minimal empty test project into M840-001-02, and if so, what exact versions/process did you use?

Any help would be appreciated.