Boot Project Load Failed (Retain Data Mismatch)

What does E3-45 mean?

The CPU failed to load the boot project because the retain data detected does not match the project's requirements. This mismatch can occur after firmware updates or project changes, causing the CPU to reject the current configuration and potentially halting operation. Data consistency is crucial.

• Project downloaded without clearing or initializing retain data after significant logic or variable changes.
• CPU firmware update altered the structure or size of retain data blocks, leading to a mismatch with existing data.
• Downloading an older project version onto a CPU that was previously running a newer project with a different retain data format.
• Manual modification of retain variable declarations in the project without a subsequent full memory re-initialization.
• Restore of a CPU backup image that is incompatible with the CPU's current firmware or hardware variant's retain data format.

Click steps to track your progress.

1. 1

   1. Connect to the CPU with programming software. Perform a full project download, explicitly selecting the option to 'Initialize Retain Data' or 'Clear Retain Memory'.

2. 2

   2. Verify that the project version being loaded is compatible with the CPU's current firmware version.

3. 3

   3. If a CPU firmware update was recently performed, ensure the associated project was recompiled or updated for compatibility with the new firmware.

4. 4

   4. Review project parameters related to retain data memory allocation or structure (e.g., Parameter P5-12 Retain Block Size).

5. 5

   5. Before downloading, back up the current project to disk; then attempt a full CPU memory reset (excluding firmware) and reload the project.