CHIP-SELECT UNIT

Internal

 

 

 

 

 

Address Bus

 

 

 

 

 

= Block Size

UCS

 

 

 

 

= Block Size

LCS

 

 

 

 

= Block Size/4

MCS3

 

 

 

 

= Block Size/4

MCS2

 

 

 

 

= Base

MCS1

 

 

 

 

= Block Size/4

 

 

 

 

= Block Size/4

MCS0

 

 

 

 

= Base

Base + 0

 

PCS0

 

 

 

Base + 128

PCS1

 

 

Memory/

Base + 256

PCS2

 

 

Base + 384

PCS3

 

 

I/O Selector

 

 

 

 

 

 

 

MS

Base + 512

PCS4

 

 

 

Base + 640

 

 

 

 

Base + 768

 

 

 

 

 

 

A

MUX

PCS5

 

 

A1

 

Internal Address Bit

B

A/B

PCS6

A2

 

 

 

 

 

 

 

EX Control Bit

 

 

 

 

 

 

 

A1139-0A

Figure 6-2. Chip-Select Block Diagram

6-3

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Image 158
Intel 80C188XL, 80C186XL user manual MCS3, MCS2, MCS1, PCS1, PCS2, PCS3, PCS4, MUX PCS5, PCS6