Table 279
+=====-========-========-========-========-========-========-========-========+
| Bit| 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
|Byte | | | | | | | | |
|=====+=======================================================================|
| 0 | (MSB) |
|-----+--- ---|
| 1 | Data buffer status length |
|-----+--- ---|
| 2 | (LSB) |
|-----+-----------------------------------------------------------------------|
| 3 | Reserved | Block |
|=====+=======================================================================|
| | Data buffer status descriptor(s) |
|=====+=======================================================================|
| 0 | Window identifier |
|-----+-----------------------------------------------------------------------|
| 1 | Reserved |
|-----+-----------------------------------------------------------------------|
| 2 | (MSB) |
|-----+--- ---|
| 3 | Available data buffer |
|-----+--- ---|
| 4 | (LSB) |
|-----+-----------------------------------------------------------------------|
| 5 | (MSB) |
|-----+--- ---|
| 6 | Filled data buffer |
|-----+--- ---|
| 7 | (LSB) |
+=============================================================================+