CONTENTS
viii
10.1.3
DMA Requests ........................................................................................................10-3
10.1.4
External Requests ...................................................................................................10-4
10.1.4.1
Source Synchronization ................................................................................10-5
10.1.4.2
Destination Synchronization ..........................................................................10-5
10.1.5
Internal Requests ....................................................................................................10-6
10.1.5.1
Timer 2-Initiated Transfers ............................................................................10-6
10.1.5.2
Unsynchronized Transfers ............................................................................10-6
10.1.6
DMA Transfer Counts .............................................................................................10-7
10.1.7
Termination and Suspension of DMA Transfers .....................................................10-7
10.1.7.1
Termination at Terminal Count ......................................................................10-7
10.1.7.2
Software Termination ....................................................................................10-7
10.1.7.3
Suspension of DMA During NMI ...................................................................10-7
10.1.7.4
Software Suspension ....................................................................................10-7
10.1.8
DMA Unit Interrupts ................................................................................................10-8
10.1.9
DMA Cycles and the BIU ........................................................................................10-8
10.1.10 The Two-Channel DMA Unit ...................................................................................10-8
10.1.10.1
DMA Channel Arbitration ...............................................................................10-8
10.2
PROGRAMMING THE DMA UNIT ............................................................................ 10-10
10.2.1
DMA Channel Parameters ....................................................................................10-10
10.2.1.1
Programming the Source and Destination Pointers ....................................10-10
10.2.1.2
Selecting Byte or Word Size Transfers ........................................................10-14
10.2.1.3
Selecting the Source of DMA Requests ......................................................10-17
10.2.1.4
Arming the DMA Channel ............................................................................10-18
10.2.1.5
Selecting Channel Synchronization .............................................................10-18
10.2.1.6
Programming the Transfer Count Options ...................................................10-18
10.2.1.7
Generating Interrupts on Terminal Count ....................................................10-19
10.2.1.8
Setting the Relative Priority of a Channel ....................................................10-19
10.2.2
Suspension of DMA Transfers ..............................................................................10-20
10.2.3
Initializing the DMA Unit ........................................................................................10-20
10.3
HARDWARE CONSIDERATIONS AND THE DMA UNIT ......................................... 10-20
10.3.1
DRQ Pin Timing Requirements .............................................................................10-20
10.3.2
DMA Latency ........................................................................................................10-21
10.3.3
DMA Transfer Rates .............................................................................................10-21
10.3.4
Generating a DMA Acknowledge ..........................................................................10-22
10.4
DMA UNIT EXAMPLES ............................................................................................. 10-22
CHAPTER 11
MATH COPROCESSING
11.1
OVERVIEW OF MATH COPROCESSING .................................................................. 11-1
11.2
AVAILABILITY OF MATH COPROCESSING.............................................................. 11-1
11.3
THE 80C187 MATH COPROCESSOR........................................................................ 11-2
11.3.1
80C187 Instruction Set ...........................................................................................11-2
11.3.1.1
Data Transfer Instructions .............................................................................11-3
11.3.1.2
Arithmetic Instructions ...................................................................................11-3
11.3.1.3
Comparison Instructions ................................................................................11-5
Содержание 80C186XL
Страница 1: ...80C186XL 80C188XL Microprocessor User s Manual...
Страница 2: ...80C186XL 80C188XL Microprocessor User s Manual 1995...
Страница 18: ...1 Introduction...
Страница 19: ......
Страница 27: ......
Страница 28: ...2 Overview of the 80C186 Family Architecture...
Страница 29: ......
Страница 79: ......
Страница 80: ...3 Bus Interface Unit...
Страница 81: ......
Страница 127: ......
Страница 128: ...4 Peripheral Control Block...
Страница 129: ......
Страница 137: ......
Страница 138: ...5 ClockGenerationand Power Management...
Страница 139: ......
Страница 154: ...6 Chip Select Unit...
Страница 155: ......
Страница 178: ...7 Refresh Control Unit...
Страница 179: ......
Страница 193: ......
Страница 194: ...8 Interrupt Control Unit...
Страница 195: ......
Страница 227: ......
Страница 228: ...9 Timer Counter Unit...
Страница 229: ......
Страница 253: ......
Страница 254: ...10 Direct Memory Access Unit...
Страница 255: ......
Страница 283: ......
Страница 284: ...11 Math Coprocessing...
Страница 285: ......
Страница 302: ...12 ONCE Mode...
Страница 303: ......
Страница 306: ...A 80C186 Instruction Set Additions and Extensions...
Страница 307: ......
Страница 318: ...B Input Synchronization...
Страница 319: ......
Страница 322: ...C Instruction Set Descriptions...
Страница 323: ......
Страница 371: ......
Страница 372: ...D Instruction Set Opcodes and Clock Cycles...
Страница 373: ......
Страница 396: ...Index...
Страница 397: ......