Figure 4-1 Extended Message - Data Format; Table 4–3 Extended Message — Field Description - Quantum DLT 8000 Product Manual

Messages
Bit 7
Byte
0
1
2
3
to
n - 1
Field
Extended Message Length
Extended Message Code
4-4
6 5
Extended Message (01h)
Extended Message Length
Extended Message Code
Extended Message Arguments
Figure 4–1 Extended Message — Data Format
Table 4–3 Extended Message — Field Description
Description
This field specifies the length, in bytes, of the Extended
Message Code plus the Extended Message Arguments that
follow. Therefore, the total length of the message is equal to
the Extended Message Length plus 2.
A value of 0 for the Extended Message Length indicates that
256 bytes follow.
The drive supports three Extended Messages. They are:
00h MODIFY DATA POINTER
01h SYNCHRONOUS DATA TRANSFER REQUEST
03h WIDE DATA TRANSFER REQUEST
Quantum DLT 8000 Tape System
4 3 2 1 0