Sony AIT-SDX460, Руководство по техническим характеристикам продукции

Страница: 51 / 192

Identify Packet Device 6. ATA Command Specification
SONY AIT-1 Turbo drive SDX-460V series Ver.1.0 6-9
When the command is issued, the Sony ATAPI Tape Drive sets the BSY bit to one, prepares to transfer the 256
words of device identification data to the host, sets the DRQ bit to one, clears the BSY bit to zero, and generates
an interrupt. The host may then transfer the data by reading the Data register. Table 6-3: Identify Packet Device
information defines the arrangement and meanings of the parameter words in the buffer. All reserved bits or words
are zero.
Some parameters are defined as a group of bits. A word that is defined as a set of bits is transmitted with indicated
bits on the respective data bus bit (e.g., bit 15 appears on DD15).
Some parameters are defined as a 16-bit value. A word that is defined as a 16-bit value places the most significant
bit of the value on bit DD15 and the least significant bit on bit DD0.
Some parameters are defined as 32-bit values (e.g., words 57 and 58). Such fields are transferred using two word
transfers. The Sony ATAPI Tape Drive transfers the least significant bits first, bits 15 through 0 of the value, on
bits DD (15-0) respectively. After the least significant bits have been transferred, the most significant bits, bits 31
through 16 of the value, are transferred on DD (15-0) respectively.
Some parameters are defined as a string of ASCII characters. For the string “Copyright”, the character “C” is the
first byte, the character “o” is the 2nd byte, etc. When such fields are transferred, the order of transmission is:
the 1st character (“C”) is on bits DD (15-8) of the first word,
the 2nd character (“o”) is on bits DD (7-0) of the first word,
the 3rd character (“p”) is on bits DD (15-8) of the second word,
the 4th character (“y”) is on bits DD (7-0) of the second word, etc.
Table 6-3: Identify Packet Device information
Word F/V Description
0 General configuration bit-significant information:
10=ATAPI device F 15-14
R 13 reserved
F 12-8 01=Sequential Access Device
F 7 1=removable media device
F 6-5 10=Device shall set DRQ to one within 50µs of receiving PACKET command.
R 4-3 reserved
V 2 Incomplete Response
00=12 byte command packet F 1-0
1000 0001 1000 0000 = 81C0h
1 R Reserved
2 V 0000h
3-9 R Reserved
10-19 F Serial number (20 ASCII characters)
“xxxxxxxxxxxxxxxxxxxx”
20-22 R Reserved
0000h x 3
23-26 F Firmware revision (8 ASCII characters)
“xxxxxxxx”
27-46 F Model number (40 ASCII characters)
“SONY SDX-460V”