t2
PCOBF
t1
AUXOBF1
nWRT
t3
IBF
nRD
FIGURE 6 - INTERNAL 8042 CPU TIMING
NAME
DESCRIPTION
t1 nWRT deasserted to AUXOBF1 asserted (Notes 1,2)
t2 nWRT deasserted to PCOBF asserted (Notes 1,3)
t3 nRD deasserted to IBF deasserted (Note 1)
MIN TYP MAX UNITS
40
ns
40
ns
40
ns
Note 1: IBF, nWRT and nRD are internal signals.
Note 2: PCOBF is used for the Keyboard IRQ.
Note 3: AUXOBF1 is used for the Mouse IRQ.
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