Intel 80C186XL 7.7.3Programming Example, Register Name Register Mnemonic Register Function

Models: 80C186XL 80C188XL

1 405
Download 405 pages 42.62 Kb
Page 189
Image 189
Refresh Control Register

REFRESH CONTROL UNIT

Register Name:

Register Mnemonic:

Register Function:

15

R

E

N

Refresh Control Register

RFCON

Controls Refresh Unit operation.

0

 

 

 

R

 

R

R

R

R

 

R

R

R

R

 

 

 

C

 

C

C

C

C

 

C

C

C

C

 

 

 

8

 

7

6

5

4

 

3

2

1

0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

A1311-0A

Bit

Bit Name

Reset

Function

Mnemonic

State

 

 

 

 

 

 

REN

Refresh

0

Setting REN enables the Refresh Unit. Clearing

 

Control Unit

 

REN disables the Refresh Unit.

 

Enable

 

 

 

 

 

 

RC8:0

Refresh

000H

These bits contain the present value of the

 

Counter

 

down-counter that triggers refresh requests.

 

 

 

The user cannot program these bits.

 

 

 

 

NOTE: Reserved register bits are shown with gray shading. Reserved bits must be written to a logic zero to ensure compatibility with future Intel products.

Figure 7-8. Refresh Control Register

7.7.3Programming Example

Example 7-1 contains sample code to initialize the Refresh Control Unit. Example 5-2 on page 5-14 shows the additional code to reprogram the Refresh Control Unit upon entering Power-Save mode.

7-10

Page 189
Image 189
Intel 80C186XL 7.7.3Programming Example, Register Name Register Mnemonic Register Function, Refresh Control Register RFCON