BUS INTERFACE UNIT

CLKOUT

ALE

S2:0

AD15:0

[AD7:0]

[A15:8]

A19:16

BHE

RFSH

NOTES:

 

Addr

 

Note 1

 

Address

Note 1

Addr

A19 = 1, A18:16 = 0

Note 2

 

Note 3

1.Previous bus cycle value.

2.Only occurs for BHE on the first refresh bus cycle after entering HALT.

3.BHE = 1 for 16-bit device, RFSH = 0 for 8-bit device.

A1514-0A

Figure 3-27. Returning to HALT After a Refresh Bus Cycle

3-31

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Intel 80C188XL, 80C186XL user manual S20 AD150 AD70 A158 A1916, BHE Rfsh