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Table 3.18 decode of mad[3:1] pins, Decode of mad[3:1] pins – Avago Technologies LSI53C896 User Manual

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MAD Bus Programming

3-23

Version 3.3

Copyright © 1998–2003 by LSI Logic Corporation. All rights reserved.

MAD[3:1] – These pins set the size of the external expansion ROM
device attached. Encoding for these pins is listed in

Table 3.18

(“0” indicates a pull-down resistor is attached; “1” indicates a pull-up
resistor attached).

MAD[0], slow ROM – When pulled up, it enables two extra cycles of
data access time to allow use of slower memory devices.

Note:

All MAD pins have internal pull-down resistors.

Table 3.18

Decode of MAD[3:1] Pins

MAD[3:1]

Available Memory Space

000

16 Kbytes

001

32 Kbytes

010

64 Kbytes

011

128 Kbytes

100

256 Kbytes

101

512 Kbytes

110

1024 Kbytes

111

no external memory present