An error was encountered during issuance of mode control CCWs for device number nnnn. The error prevents setting the mode control page values. When these controls are not properly set, the device cannot be brought online.
Mode control CCWs set certain attributes of the device in a manner well-defined for normal MVS™ processing.
The device is boxed.
Once the cause of the error has been determined and corrected, the device can be varied online. Varying the device online before the error is corrected may cause the error to occur again.
Collect diagnostic data such as GTF traces for I/O and any system logs that are available. Follow your installation's procedures for reporting this error.
Asynchronous Operation Manager Attention Processing Routine for Tape Devices (AOMATTNT)