Hitachi 7K400 Specifications - Page 148
Streaming Access Latency - DMA and PIO
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Table 95: Identify device information (Part 6 of 7) Word 93 Content XXXXH Description Hardware reset result. Bit assignments 15-14 (=01) Word 93 is valid 13 CBLID- status 1=above Vih 0=below Vil 12- 8 Device 1 hardware reset result Device 0 clear these bits to 0 12 Reserved 11 PDIAG- assertion 1 = asset 0 = not assert 10-9 How to determine the device number: 00= Reserved 01= a jumper was used 10= the CSEL signal was used 11= some other method used or method unknown 8 Shall be set to one if Device 1 7- 0 Device 0 hardware reset result 7 Reserved 6 Respond for Device 1 1= respond 0= not respond 5 DASP- detection 1= detect 0= not detect 4 PDIAG- detection 1= pass 0= fail 3 Device 0 diagnostic 1= pass 0= fail 2-1 How to determine the device number 00=Reserved 01=Jumper 10=CSEL signal 11=Other method 0 Shall be set to one if Device 0 94 XXXXH Current Advanced Acoustic Management value 15- 8 Vendor's Recommended Acoustic Management level 7- 0 Current Acoustic Management level 95 xxxxH Stream Minimum Request Size Number of sectors that provides optimum performance in streaming environment. This number shall be a power of two, with a minimum of eight sectors (4096 bytes). The starting LBA value for each stream- ing command should be evenly divisible by this request size. 96 xxxxH Streaming Transfer Time - DMA The worst-case sustainable transfer time per sector for the device is calculated as follows: Streaming Transfer Time = (word 96) * (words(99:98) / 65536) If the Streaming Feature set is not supported by the device, the content of word 96 shall be zero. 97 xxxxH Streaming Access Latency - DMA and PIO The worst-case access latency of the device for a streaming command is calculated as follows: Access Latency = (word 97) * (words(99:98) / 256) If the Streaming Feature set is not supported by the device, the content of word 97 shall be zero. Deskstar 7K400 Hard Disk Drive Specification 134
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