MATH COPROCESSING
11-6
11.3.1.5 Constant Instructions
Each constant instruction (see Table 11-5) loads a commonly used constant onto the stack. The
values have full 80-bit precision and are accurate to about 19 decimal digits. Since a temporary
real constant occupies 10 memory bytes, the constant instructions, only 2 bytes long, save mem-
ory space.
11.3.1.6 Processor Control Instructions
Computations do not use the processor control instructions; these instructions are available for
activities at the operating system level. This group (see Table 11-6) includes initialization, excep-
tion handling and task switching instructions.
Table 11-5. 80C187 Constant Instructions
FLDZ
Load + 0.1
FLD1
Load +1.0
FLDPI
Load
FLDL2T
Load log
2
10
FLDL2E
Load log
2
e
FLDLG2
Load log
10
2
FLDLN2
Load log
e
2
Table 11-6. 80C187 Processor Control Instructions
FINIT/FNINIT
Initialize processor
FLDENV
Load environment
FDISI/FNDISI
Disable interrupts
FSAVE/FNSAVE
Save state
FENI/FNENI
Enable interrupts
FRSTOR
Restore state
FLDCW
Load control word
FINCSTP
Increment stack pointer
FSTCW/FNSTCW
Store control word
FDECSTP
Decrement stack pointer
FSTSW/FNSTSW
Store status word
FFREE
Free register
FCLEX/FNCLEX
Clear exceptions
FNOP
No operation
FSTENV/FNSTENV
Store environment
FWAIT
CPU wait
Summary of Contents for 80C186EA
Page 1: ...80C186EA 80C188EA Microprocessor User s Manual...
Page 2: ...80C186EA 80C188EA Microprocessor User s Manual 1995...
Page 19: ......
Page 20: ...1 Introduction...
Page 21: ......
Page 28: ...2 Overview of the 80C186 Family Architecture...
Page 29: ......
Page 79: ......
Page 80: ...3 Bus Interface Unit...
Page 81: ......
Page 129: ......
Page 130: ...4 Peripheral Control Block...
Page 131: ......
Page 139: ......
Page 140: ...5 ClockGenerationand Power Management...
Page 141: ......
Page 165: ......
Page 166: ...6 Chip Select Unit...
Page 167: ......
Page 190: ...7 Refresh Control Unit...
Page 191: ......
Page 205: ......
Page 206: ...8 Interrupt Control Unit...
Page 207: ......
Page 239: ...INTERRUPT CONTROL UNIT 8 32...
Page 240: ...9 Timer Counter Unit...
Page 241: ......
Page 265: ......
Page 266: ...10 Direct Memory Access Unit...
Page 267: ......
Page 295: ...DIRECT MEMORY ACCESS UNIT 10 28...
Page 296: ...11 Math Coprocessing...
Page 297: ......
Page 314: ...12 ONCE Mode...
Page 315: ......
Page 318: ...A 80C186 Instruction Set Additions and Extensions...
Page 319: ......
Page 330: ...B Input Synchronization...
Page 331: ......
Page 334: ...C Instruction Set Descriptions...
Page 335: ......
Page 383: ...INSTRUCTION SET DESCRIPTIONS C 48...
Page 384: ...D Instruction Set Opcodes and Clock Cycles...
Page 385: ......
Page 408: ...Index...
Page 409: ......