B) Stop Frame Timing with Host using 17 IRQSER sampling period
IRQ14
FRAME
R
IRQ15
FRAME
R
IOCHCK#
FRAME
STOP FRAME
NEXT CYCLE
START3
I 2
S
T
S
T
S
R
T
H
R
T
PCICLK
IRQSER
Driver
STOP1
None
IRQ15
None
Host Controller
H=Host Control, R=Recovery, I=Idle, T=Turn-Around, S=Sample
1)
2)
3)
Stop pulse is 2 clocks wide for Quiet mode, 3 clocks wide for Continuous mode.
There may be none, one or more Idle states during the Stop Frame.
The next IRQSER cycle’s Start Frame pulse may or may not start immediately
after the turn-around clock of the Stop Frame.
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