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Rainbow Electronics W90P710CDG User Manual

Page 73

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W90P710CD/W90P710CDG

Publication Release Date: September 19, 2006

- 73 -

Revision B2

Continued.

BITS

DESCRIPTION

[3:2] BTSIZE

Boot ROM/FLASH data bus width
This ROM/Flash bank is designed for a boot ROM. BASADDR bits
determine its start address. The external data bus width is determined by
the data bus signals D [13:12] power-on setting.

BTSIZE [3:2]

Bus Width

D [13:12]

Bus Width

0 0 8-bit Pull-down Pull-down

8-bit

0 1 16-bit Pull-down Pull-up 16-bit
1 0 32-bit Pull-up

Pull-down

32-bit

1 1

RESERVED

Pull-up

Pull-up

RESERVED

[1:0] PGMODE

Page mode configuration

PGMODE [1:0]

Mode

0 0 Normal

ROM

0

1

4 word page

1

0

8 word page

1

1

16 word page


Fig6.3.2 ROM/FLASH Read Operation Timing