| Offset | Size | Description |
|---|---|---|
| 0 (0) | 1 | Device class. |
| 1 (1) | 1 | Device status. |
| 2 (2) | 1 | Error codes: indicate errors found during CCW analysis. See CCW error codes for a description. |
| 3 (3) | 1 | Flag byte. |
| 1... .... | Last trace recordof this I/O event. | |
| .1.. .... | Reserve (conditional or unconditional). | |
| ..1. .... | Release. | |
| ...1 .... | At least one search CCW. | |
| 4 (4) | 6 | Volume serial. |
| 10 (A) | 4 | Device type. |