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Access File Manager

Press the PGM MGT key, then select 'TNC:\' to access the control's internal directory structure. Navigate to the 'system' folder where oscilloscope configuration files are stored.

Before deleting files, check the file date stamps - recently modified files may indicate when the corruption occurred.

Backup and Delete Oscilloscope Files

Look for files with extensions .OSC or .TRACE in the TNC:\system\ directory. Copy these files to external storage if needed, then delete them from the system directory. Also check TNC:\service\ for oscilloscope-related temporary files.

Do not delete files you are unsure about. Focus only on oscilloscope configuration files - incorrect deletion may require software reinstallation.

Restart Control and Reinitialize Oscilloscope

Perform a cold boot by powering off the control completely, waiting 30 seconds, then powering back on. After startup, access the oscilloscope function via MOD > Oscilloscope to force creation of new default configuration files.

The first time you open the oscilloscope after file deletion, it may take longer to load as it rebuilds default settings.

Reconfigure Trace Channels

Set up a simple trace configuration with only 2-3 basic channels (e.g., axis position values) to verify communication is restored before adding complex trigger conditions or multiple channels.

Verify Software Version Consistency

Press MOD key, select 'Information about control system', and document the NC software version, PLC software version, and oscilloscope module version. All components should have matching version numbers or be within compatible revision ranges.

Write down the complete version string including build numbers - minor version mismatches often cause communication errors.

Check Software Installation Log

In the MOD function, access 'System Information' > 'Installation Log' to review recent software installations. Look for interrupted installations or error messages during the last update procedure.

Perform Complete Software Reinstallation

If version mismatch is detected, obtain the complete NC software package from Heidenhain for your control model. Use the MOD > Software Update function to perform a full reinstallation ensuring all modules are updated simultaneously.

Backup all user programs, tool tables, and parameter settings before software reinstallation. Machine parameters will need verification after update.

Initialize System After Update

After software installation completes, perform a full system initialization by going to MOD > System Settings > Initialize System. This rebuilds internal communication tables and registers all software modules.

After initialization, test the oscilloscope with a minimal configuration before restoring complex trace setups.

Check PLC Cycle Time

Access MOD > PLC Programming > PLC Monitor and observe the actual PLC cycle time. Normal values should be under 10ms. If cycle time exceeds 15-20ms, the oscilloscope communication may be interrupted.

Note the peak cycle time, not just average - intermittent spikes above 30ms can cause this alarm even if average is acceptable.

Review Recent PLC Modifications

If custom PLC programs were recently added or modified, temporarily disable non-essential PLC sections. Go to PLC Programming mode and comment out custom subroutines to isolate whether PLC load is causing the communication error.

Reduce Oscilloscope Data Load

Configure the oscilloscope with longer sampling intervals (increased time base) and fewer active channels. Start with 4 channels maximum at 1ms sampling rate to reduce system load.

High-speed oscilloscope traces with many channels can overwhelm the internal communication bus - sometimes the issue is configuration rather than malfunction.

Check for Background Tasks

In MOD > System Information > Process Monitor, verify no unexpected background tasks are consuming CPU resources. Look for stuck data logging, file transfer operations, or network processes that may compete with oscilloscope communication.