Hitachi 7K250 Specifications - Page 31

Drive ready time - deskstar 80 gb

Page 31 highlights

4.4.2.4 Cylinder switch time (cylinder skew) Cylinder switch time is defined as the amount of time required by the fixed disk to access the next sequential block after reading the last sector in the current cylinder. The measuring method is given in Section 4.4.5, "Throughput" on page 19. 4.4.2.5 Single track seek time (without command overhead, including settling) Table 8: Single track seek time Function Typical (ms) Read 0.8 Write 1.3 Read (Quiet Seek mode) 0.8 Write (Quiet Seek mode) 1.3 Max (ms) 1.5 2.0 1.5 2.0 Single track seek is measured as the average of one (1) single track seek from every track in both directions (inward and outward). 4.4.2.6 Average latency Table 9: Latency Time Rotational speed (RPM) 7200 RPM Time for one revolution (ms) 8.3 Average latency (ms) 4.17 4.4.3 Drive ready time Table 10: Drive ready time Power on to ready 80 GB models 160 GB models 250 GB models Typical (sec) 6 8 10 Maximum (sec) 31 31 31 Ready Power on The condition in which the drive is able to perform a media access command (for example- read, write) immediately. This includes the time required for the internal self diagnostics. Note: Max Power On to ready time is the maximum time period that Device 0 waits for Device 1 to assert PDIAG. Deskstar 7K250 Hard Disk Drive Specification 17

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Deskstar 7K250 Hard Disk Drive Specification
17
4.4.2.4
Cylinder switch time (cylinder skew)
Cylinder switch time is defined as the amount of time required by the fixed disk to access the next sequential block
after reading the last sector in the current cylinder.
The measuring method is given in Section 4.4.5, “Throughput” on page 19.
4.4.2.5
Single track seek time (without command overhead, including settling)
Single track seek is measured as the average of one (1) single track seek from every track in both directions
(inward and outward).
4.4.2.6
Average latency
4.4.3
Drive ready time
Ready
The condition in which the drive is able to perform a media access command (for exam-
ple- read, write) immediately.
Power on
This includes the time required for the internal self diagnostics.
Note:
Max Power On to ready time is the maximum time period that Device 0 waits for Device 1 to assert PDIAG.
Table 8: Single track seek time
Function
Typical (ms)
Max (ms)
Read
0.8
1.5
Write
1.3
2.0
Read (Quiet Seek mode)
0.8
1.5
Write (Quiet Seek mode)
1.3
2.0
Table 9: Latency Time
Rotational speed
(RPM)
Time for one
revolution (ms)
Average latency
(ms)
7200 RPM
8.3
4.17
Table 10: Drive ready time
Power on to ready
Typical (sec)
Maximum (sec)
80 GB models
6
31
160 GB models
8
31
250 GB models
10
31