HP C2246 Technical Reference Manual page 15

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Operating Specifications
Table 1-2. HP C2244/45/46/47 Operating Specifications
Note: The HP C2244/45/46/46 disk drives must be operated within the Disk Drive Environmental
Requirements specified in Table 1-4 in order for them to function properly.
Interface ............................................................. Industry Standard SCSI-2
Controller:
Overhead time ...........................................................
<
500 microseconds
Buffer size ............................................................. ; ........... 256 kbytes
Buffer type ...................................................................... Dual-ported
Sector size .. . .. .. . . .. .. . .. . .. . . . . . . . ............................. 180 - 7 44 Data Field Bytes
Interleave ................................................................................. 1:1
Seek Times (includes settling time)
Track to Track Seek .......................................................... 2.5 milliseconds
Head Switch Time ............................................................
<
1 millisecond
Average Random Seek
Reads .................................................................... 10.2 milliseconds
Writes .................................................................... 11.2 milliseconds
Maximum Seek ............................................................... 22 milliseconds
Notes:
Seek time is defined
as
the time from when the actuator begins to move until the head has
settled over the target track. It does not include any controller overhead time or any initiator
overhead time. The values above are derived from a representative sample of disk drives
measured under normal temperature and voltage conditions.
Track to track seek time is the mean value of all seek times measured when performing all
possible single track seeks.
Average random seek time is the time to do all possible seeks divided by the number of seeks
possible.
Maximum seek time is the time it takes to seek 2051 physical cylinders.
Spin-up Time
From Power-On to Ready for Access
Typical: . . . . . . . . . . . . . . . . . . . . . . . . . .............................................. 14 seconds
From Power-On to SCSI Bus Selection
Typical: ....................................... , ................................. 3 seconds
Maximum: ....................................................................... 5 seconds
Disk Rotating Speed ........................................................... 5400 rpm ±0.5%
Rotational Latency (Average time) ..................................... 5.56 milliseconds ±0.5%
futernal Data Transfer Rates (Controller/Disk) .
Burst Rates (for single sector transfers):
Inner Zone to Outer Zone ................. 3.1 to 5.3 Mbytes (24.8 to 42.4 Mbits) per second
Sustained Rates: (for continuous transfers; excludes controller overhead)
Inner Zone to Outer Zone ................. 2.1 to 3.7 Mbytes (17.1 to 29.5 Mbits) per second
Product Specifications
1-5