CONTENTS
vi
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
Summary of Contents for 80C186XL
Page 1: ...80C186XL 80C188XL Microprocessor User s Manual...
Page 2: ...80C186XL 80C188XL Microprocessor User s Manual 1995...
Page 18: ...1 Introduction...
Page 19: ......
Page 27: ......
Page 28: ...2 Overview of the 80C186 Family Architecture...
Page 29: ......
Page 79: ......
Page 80: ...3 Bus Interface Unit...
Page 81: ......
Page 127: ......
Page 128: ...4 Peripheral Control Block...
Page 129: ......
Page 137: ......
Page 138: ...5 ClockGenerationand Power Management...
Page 139: ......
Page 154: ...6 Chip Select Unit...
Page 155: ......
Page 178: ...7 Refresh Control Unit...
Page 179: ......
Page 193: ......
Page 194: ...8 Interrupt Control Unit...
Page 195: ......
Page 227: ......
Page 228: ...9 Timer Counter Unit...
Page 229: ......
Page 253: ......
Page 254: ...10 Direct Memory Access Unit...
Page 255: ......
Page 283: ......
Page 284: ...11 Math Coprocessing...
Page 285: ......
Page 302: ...12 ONCE Mode...
Page 303: ......
Page 306: ...A 80C186 Instruction Set Additions and Extensions...
Page 307: ......
Page 318: ...B Input Synchronization...
Page 319: ......
Page 322: ...C Instruction Set Descriptions...
Page 323: ......
Page 371: ......
Page 372: ...D Instruction Set Opcodes and Clock Cycles...
Page 373: ......
Page 396: ...Index...
Page 397: ......