Rainbow Electronics DS31256 - Manual (Page 152)

DS31256
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Figure 11-4. Local Bus Access Flowchart
PCI Host Initiates a
Local Bus Access
Is Arbitration Enabled
for the Local Bus?
Is the Local Bus
Granted?
Is the External Local Bus
Ready (
LRDY) Being Used?
Normal Access
Occurs
Local Bus Access
Progresses
Local Bus Access
Progresses
Timer Expired?
LRDY Active?
Start 9 Clock Timer
Set the LBE Status Bit
No
Yes
Yes
No
No
No
Yes
Yes
No
Yes
PCI Target Retry
Issued
Are there 16 Clocks
Remaining?
No
Yes
Request
the Bus