Seagate Medalist 1640, Руководство по эксплуатации продукта

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Appendix. Timing diagrams
The ST31640A and ST32140A are designed to comply with and can
exceed the ATA-2 timing standards. Performance in excess of the ATA-2
standard depends on the capability of the host-system environment. See
your Seagate representative for additional details.
Without IORDY, the drive operates at programmed I/O timing specifica-
tions, as shown below.
Time Description Min Max
T0 Cycle time 120 nsec ----
T1
Drive address (CS1FX--, CS3FX--,
DA0, DA1 and DA2) valid and
DIOR--/DIOW-- setup
25 nsec ----
T2 DIOW-- or DIOR-- pulse width 70 nsec ----
T3 DIOW-- data setup 20 nsec ----
T4 DIOW-- data hold 10 nsec ----
T5 DIOR-- data setup 20 nsec ----
T6 DIOR-- data hold 5 nsec ----
T7
Address valid until I/OCS16-- is
asserted
---- ----
T8 Address invalid to I/OCS16-- tristate ---- ----
T9 DIOR-- false to address valid hold 10 nsec ----
Figure 8. Programmed I/O timing without IORDY
Medalist 1640 and 2140 Product Manual, January 1996 35