FUJITSU MB91460 SERIES FR60 User Manual

Page 538

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Chapter 31 External Bus

2.External Bus Interface Registers

[Bits 15-12] W15-12 (First Wait Cycle)

These bits set the number of auto-wait cycles to be inserted into the first access cycle of each cycle. Except
for the burst access cycles, only this wait setting is used.

Table 2-5

"Settings for the Number of Auto-Wait Cycles (During First Access)" lists the settings for the number

of auto-wait cycles during first access.

[Bits 11-8] W11-08 (Inpage Access Wait Cycle)

These bits set the number of auto-wait cycles to be inserted into the inpage access cycle during burst access.
They are valid only for burst cycles.

Table 2-6

"Settings for the Number of Auto-Wait Cycles (During Burst Access)" lists the settings for the

number of auto-wait cycles during burst access.

If the same value is set for the first access wait cycle and inpage access wait cycle, the access time for the
address in each access cycle is not the same. This is because the inpage access cycle contains an address
output delay.

Table 2-5 Settings for the Number of Auto-Wait Cycles (During First Access)

W15

W14

W13

W12

First access wait cycle

0

0

0

0

Auto-wait cycle 0

0

0

0

1

Auto-wait cycle 1

...

...

1

1

1

1

Auto-wait cycle 15

Table 2-6 Settings for the Number of Auto-Wait Cycles (During Burst Access)

W11

W10

W09

W08

Inpage access wait cycle

0

0

0

0

Auto-wait cycle 0

0

0

0

1

Auto-wait cycle 1

...

...

1

1

1

1

Auto-wait cycle 15

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