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Command Specifications
(3) Mode = 0, 0, 1, 0: Data only, with address specification
In this mode, data transfer from the INIT includes buffer data only without the 4-
byte header being added.
The top address of the data buffer where the data transferred from the INIT are to
be stored can be specified in the "Buffer address" field.
The "Transfer byte length" field in the CDB specifies the total number of bytes of
data transferred by the INIT. The IDD stores data transferred from the INIT in the
data buffer beginning at the byte position specified in the "Buffer address" field
in the CDB.
Furthermore, a value less than the ["IDD's buffer size" – value specified in the
"Buffer address" field] 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.
(4) Mode = 0, 1, 0, 0: Microcode download, without saving
In this mode, the controller's microcode or control information is transferred to
the IDD's control memory area. "0" must be specified in the "Buffer ID" field
and the "Buffer address" field.
The "Transfer byte length" field specifies the total number of transfer bytes of
data transferred from the INIT.
When downloading of microcode is completed, the IDD generates a UNIT
ATTENTION condition for all the INITs. At this time, the IDD performs
microprogram reboot and generates sense data.
The IDD operates according to this microcode until its power is switched off. If
the power is switched on again, the IDD's operation returns to the existing
microcode saved previously on the disk.
(5) Mode = 0, 1, 0, 1 : Microcode download, with saving
In this mode, the controller's microcode or control information is transferred to
the IDD's control memory area and written to the disk. "0" must be specified in
the "Buffer ID" field and the "Buffer address" field.
The "Transfer byte length" field specifies the total number of transfer bytes of
data transferred from the INIT.
When all the data have been received, the IDD writes the new microcode to the
disk's system area and operates in accordance with the old microcode until new
microcode is downloaded.
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C141-C012
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