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Here's another old comment I thought was incorporated but did not make it into ata7v3r4. The maximum T,UI (section 14.4.10, table 11, page 61) should be 670.23, not 670.12 ps. History: In SATA 1.0 and SATA 1.0a, Table 11 "General electrical specifications" (6.6.2 page 76) defines T,UI as 666.43 ps minimum and 670.12 ps maximum. When I calculate 666.666 ps +350/-5350 ppm, I get a minimum of 666.43 ps (agrees with SATA) and a maximum of 670.233 ps (slightly differs from SATA). SATA 1.0 defined the frequency skew as +350/-2650 ppm, noting it included +350/-150 ppm for the crystal and -0.25% [= -2500 ppm] fixed skew for SSC but excluded +/-0.25% [= +2500/-2500 ppm] AC modulation from SSC. That adds up to +2850/-5150. SATA 1.0a defines the frequency skew as +/- 350 for DC skew and +0/-5000 for AC skew (adding up to +350/-5350). The minimum T,UI is not based on +2850, it's based on +350: 666.666 * (1 - .00285) = 664.76666 666.666 * (1 - .000350) = 666.4333 so the SATA 1.0a change makes the minimum agree. The maximum of 670.12 ps is based on -5150 rather than -5350: 666.666 * 1.005150 = 670.10 (SATA 1.0 maximum, with 2 fs rounding discrepency) 666.666 * 1.005350 = 670.23 (SATA 1.0a maximum) For SATA 1.0a, it should be based on -5350ppm and be 670.23 ps. -- Rob Elliott, [EMAIL PROTECTED] Hewlett-Packard Industry Standard Server Storage Advanced Technology https://ecardfile.com/id/RobElliott
