IBM 3270 error recovery analysis

When the IBM® 3270 detects an error, it sends the processor one of four sense-status messages.

• Intervention required, such as printer out of paper
• DEVICE END, which indicates the end of an operation
• DEVICE BUSY, normally caused by an operational error
• Hardware I/O error within the 3270 complex, such as a data check, control check, or equipment check

If IMS receives a sense-status message other than a DEVICE END, it issues message DFS973I.