Table 2.8 Wide Mode Setting Request From The Init To The Hdd - Fujitsu MBA3073 SERIES Technical Manual

ended in error, the transfer width between it and the INIT, and the synchronous mode will
change to the default transfer mode.
Note:
When the INIT requests for a change of data bus width, the HDD responds to the
request. At this time, the current synchronous transfer mode is reset to the default
asynchronous transfer mode. If the INIT wishes to start data transfer in the
synchronous transfer mode, the INIT and the HDD shall exchange the
SYNCHRONOUS DATA TRANSFER REQUEST message after the exchange of
WIDE DATA TRANSFER REQUEST message.
c. Wide mode setting from the INIT to the HDD
Table 2.8 lists the responses by the HDD when the INIT first sends the WIDE DATA
TRANSFER REQUEST message for request of data bus width setup. Also, this table lists the data
bus width to be set between the INIT and HDD, depending on the HDD response to the message.
Table 2.8
Message from INIT
X'00'
W
D
X'01'
T
R
X'02' or larger
d. Wide mode setting from the HDD to the INIT
If the WIDE DATA TRANSFER REQUEST message is enabled to send by the CHANGE
DEFINITION command, and if the default 8-bit data bus width mode has been selected
between the HDD and the INIT, the HDD executes one of the following operations when it
receives the command from the INIT:
(a) With ATTENTION condition
If the HDD cannot receive the WIDE DATA TRANSFER REQUEST message form the
INIT after the COMMAND phase has completed, the HDD tries to set the data bus width
by sending the WIDE DATA TRANSFER REQUEST message to the INIT.
Table 2.9 lists the contents of WIDE DATA TRANSFER REQUEST message to be sent
by the HDD, and the data bus width to be set between the HDD and INIT when the
message is responded by the INIT.
If the INIT does not respond to the WIDE DATA TRANSFER REQUEST message, the
HDD considers that the wide mode data transfer is impossible and sets the 8-bit data bus
width between the HDD and the INIT.
However, on the LVD machine in the 8-bit fixed mode (13 and 14 of CN2 are shorted),
the HDD does not send the WIDE DATA TRANSFER REQUEST message.
C141-C015
Wide mode setting request from the INIT to the HDD
Response message from HDD
Transfer Width Exponent = '00'
Transfer Width Exponent = '00'
Transfer Width Exponent = '01'
Transfer Width Exponent = '01'
Transfer width to be set
8-bit width
8-bit width
16-bit width
16-bit width
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