4.4 Maintenance, Diagnostic Commands

Table 4.61 WRITE BUFFER command: buffer data (mode = 000, 001)

Header

Data

 

Bit

7

6

5

 

4

3

 

2

1

0

Byte

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0

 

0

0

0

0

0

 

0

0

0

 

 

 

 

 

 

 

 

 

 

 

1

 

0

0

0

0

0

 

0

0

0

 

 

 

 

 

 

 

 

 

 

 

2

 

0

0

0

0

0

 

0

0

0

 

 

 

 

 

 

 

 

 

 

 

3

 

0

0

0

0

0

 

0

0

0

 

 

 

 

 

 

 

 

 

4

 

 

 

 

Buffer Data (Byte 0)

 

 

 

 

 

 

 

 

 

 

 

 

5

 

 

 

 

Buffer Data (Byte 1)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

~

~

 

~

~

~

 

~

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

n

 

Buffer Data (Byte n–4)

 

 

 

 

 

 

 

 

(2) Mode = 0, 0, 0, 1: Header + data, with address specification

The format of data transferred from the INIT in this mode must be the same as in the case of Mode = 0, 0, 0, 0, and the 4-byte header (with zero specified in all its contents) must be added to them.

In this mode, the top address of the data buffer where the data transferred from the INIT are stored can be specified in the "Buffer address" field in the CDB.

The "Transfer byte length" field in the CDB specifies the total number of bytes of data transferred by the INIT. The transfer byte count specification includes the 4 bytes of the header. The HDD stores data transferred from the INIT, in a length in which the number of bytes in the header has been deleted from the data ("Transfer byte length" – 4 bytes) in the data buffer beginning at the byte position specified in the "Buffer address" field in the CDB.

Furthermore, a value less than the ["HDD's buffer size" – value specified in the "Buffer address" field – 4 bytes] must be specified in the "Transfer byte length" field in the CDB. When a value larger than that is specified, data transfer is not executed with the INIT. Also, when zero is specified in the "Transfer byte length" field, this command is terminated without data transfer being executed.

C141-C013

265

Page 269
Image 269
Fujitsu MBA3073RC Write Buffer command buffer data mode = 000, Mode = 0, 0, 0, 1 Header + data, with address specification