Commands128
Short Form Block ID
Returned data fields:
7 6 5 4 3 2 1 0
0 BOP EOP LOCU (1) BYCU (1) Rsvd (0) LOLU (0) PERR Rsvd (0)
1 Partition Number (0)
2
Reserved (0)
3
4 (MSB)
First Block Location
7 (LSB)
8 (MSB)
Last Block Location
(same as First Block Location)
11 (LSB)
12 Reserved (0)
13 (MSB)
Number of blocks in buffer (0)
15 (LSB)
16 (MSB)
Number of bytes in buffer (0)
19 (LSB)
BOP 0 The current logical position is not at BOM (beginning of media).
1 The current logical position is at BOM.
EOP 1 The current logical position is within the EW-EOM region.
LOCU 1 The number of blocks in the buffer is unknown.
BYCU 1 The number of bytes in the buffer is unknown.
LOLU 0 The Partition Number, First Block Location and Last Block Location fields are
valid.
PERR 0No position error
1 There has been a position error caused by the overflow of some position field
data.
Partition Number This will always be zero.
First Block
Location
The number of blocks and filemarks from BOM to the current position. Counting starts
at zero, so BOM is block location 0.
Last Block
Location
Always set to the value of the First Block Location.
