Seagate ST35040A, Product Manual

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Appendix. Timing diagrams
Without IORDY, the drives operate at programmed I/O timing specifica-
tions, as shown below.
Time Description Min Max
T0 Cycle time 200 nsec —
T1
Drives address (CS1FX–, CS3FX–,
DA0, DA1 and DA2) valid and
DIOR– and DIOW setup
30 nsec —
T2 DIOW– or DIOR– pulse width 80 nsec —
T3 DIOW– data setup 30 nsec —
T4 DIOW– data hold 15 nsec —
T5 DIOR– data setup 20 nsec
T6 DIOR– data hold 5 nsec —
T7 DIOW– or DIOR– to address valid hold — 40 nsec
T8 DIOW– false to write data hold — 30 nsec
T9 DIOR– false to read data hold 10 nsec
Address valid
DIOR
−
and DIOW
−
Write data valid
Read data valid
IOCS16
−
T7
T1
T2
T3
T5 T6
T4
T0
T9 T8
Figure 8. Programmed I/O timing without IORDY
Medalist Pro 6450/5040 Product Manual, February 1997 37