CONTENTS

 

6.4.5 Memory or I/O Bus Cycle Decoding

6-17

6.4.6

 

Programming Considerations

6-17

6.5

CHIP-SELECTS AND BUS HOLD

6-18

6.6

EXAMPLES

6-18

6.6.1 Example 1: Typical System Configuration

6-18

CHAPTER 7

 

REFRESH CONTROL UNIT

 

7.1

THE ROLE OF THE REFRESH CONTROL UNIT

7-2

7.2

REFRESH CONTROL UNIT CAPABILITIES

7-2

7.3

REFRESH CONTROL UNIT OPERATION

7-2

7.4

REFRESH ADDRESSES

7-4

7.5

REFRESH BUS CYCLES

7-5

7.6

GUIDELINES FOR DESIGNING DRAM CONTROLLERS

7-5

7.7

PROGRAMMING THE REFRESH CONTROL UNIT

7-7

7.7.1 Calculating the Refresh Interval

7-7

7.7.2 Refresh Control Unit Registers

7-7

7.7.2.1

Refresh Base Address Register

7-8

7.7.2.2

Refresh Clock Interval Register

7-8

7.7.2.3

Refresh Control Register

7-9

7.7.3

 

Programming Example

7-10

7.8

REFRESH OPERATION AND BUS HOLD

7-12

CHAPTER 8

 

INTERRUPT CONTROL UNIT

 

8.1

FUNCTIONAL OVERVIEW

8-1

8.2

MASTER MODE

8-2

8.2.1 Generic Functions in Master Mode

8-2

8.2.1.1

Interrupt Masking

8-3

8.2.1.2

Interrupt Priority

8-3

8.2.1.3

Interrupt Nesting

8-4

8.3

FUNCTIONAL OPERATION IN MASTER MODE

8-5

8.3.1

 

Typical Interrupt Sequence

8-5

8.3.2

 

Priority Resolution

8-5

8.3.2.1

Priority Resolution Example

8-6

8.3.2.2

Interrupts That Share a Single Source

8-7

8.3.3 Cascading with External 8259As

8-7

8.3.3.1

Special Fully Nested Mode

8-8

8.3.4

 

Interrupt Acknowledge Sequence

8-9

8.3.5

 

Polling

8-9

8.3.6 Edge and Level Triggering

8-10

8.3.7 Additional Latency and Response Time

8-10

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Intel 80C186XL, 80C188XL user manual Chapter Refresh Control Unit