| VERIFY | 13h |
VERIFY verifies one or more blocks beginning with the next block on the tape. The verification is media verification only. It reads data from the tape as it would for a read but then immediately discards it. No data is transferred between the host and drive.
The command is identical to the READ command in most respects. The
•No data phases occur during verification.
•The Verify command has no SILI bit. When an illegal length record is encountered, Verify behaves like READ with the SILI bit clear.
NOTE: Verify will not complete until all data has been read. It does support the ANSI “byte compare” or “Immed” options (see the ANSI SCSI specification).
Illegal Field | Fixed Bit | Reservation | Deferred Error |
Unit Attention | Media Access | Diagnostic Status |
|
Command descriptor block:
|
| 7 | 6 | 5 | 4 |
| 3 | 2 | 1 | 0 |
|
|
|
|
|
|
|
|
|
| |
| 0 |
|
|
| Operation | Code (13h) |
|
|
| |
|
|
|
|
|
|
|
|
|
| |
| 1 |
|
| Reserved (0) |
|
| Immed(0) | BCmp(0) | Fixed | |
|
|
|
|
|
|
|
|
|
|
|
| 2 | (MSB) |
|
|
|
|
|
|
|
|
| 3 |
|
|
| Verification Length |
|
|
| ||
|
|
|
|
|
|
| ||||
|
|
|
|
|
|
|
|
|
|
|
| 4 |
|
|
|
|
|
|
|
| (LSB) |
|
|
|
|
|
|
|
|
|
| |
| 5 |
|
|
|
| Control |
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
CDB fields:
Immed | 0 | The Immediate Reporting option is not supported, so this bit must be 0. |
|
|
|
BCmp | 0 | The Byte compare option is not supported, so this bit must be 0. |
|
|
|
Fixed | 0 | The Verification Length field specifies the length of the data to be verified in bytes. |
| 1 | The Verification field specifies the length of the data to be verified in blocks. The size |
|
| of each block (in bytes) is specified by the current block length specified in the Mode |
|
| Parameter block descriptor. |
|
|
|
Verification | 0 | No data is verified. This is not considered an error and the current logical position |
Length |
| will be unchanged. |
| >0 | The amount of data to be verified, in bytes or blocks as specified by the Fixed field. |
|
|
|
Commands
VERIFY 13h 177