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Figure 11-4. local bus access flowchart, Figure 11-4 – Rainbow Electronics DS31256 User Manual

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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