6 system design alternatives, Figure 329. exiting halt – Intel 80C188XL User Manual

Page 114

Advertising
background image

3-33

BUS INTERFACE UNIT

Figure 3-29. Exiting HALT

3.6

SYSTEM DESIGN ALTERNATIVES

Most system designs require no signals other than those already provided by the BIU. However,
heavily loaded bus conditions, slow memory or peripheral device performance and off-board de-
vice interfaces may not be supported directly without modifying the BIU interface. The following
sections deal with topics to enhance or modify the operation of the BIU.

CLKOUT

AD15:0
[AD7:0]

ALE

[A15:8]

A19:16

Note 2

NOTES: 1. For NMI, delay = 4 1/2 clocks. For INTx, delay = 7 1/2 clocks (min).
2. Previous bus cycle value.

S2:0

BHE

RFSH

Note 2

NMI/INTx

Addr

Note 2

Note 2

Note 1

Valid

Address

Addr

A1517-0A

Advertising
This manual is related to the following products: