Instruction Set
4-228
STC
Set Carry Flag
STC
What It Does
STC sets the Carry Flag (CF) to 1.
Syntax
Description
STC sets CF.
Operation It Performs
Flag Settings After Instruction
Examples
This example rotates the bits of a word in memory, maintaining a 1 in the low bit of the word.
Form
Opcode
Description
Clocks
Am186 Am188
STC
F9
Set the Carry Flag to 1
2
2
STC
/* set carry flag */
CF = 1;
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Processor Status
Flags Register
reserved
OF DF
IF TF SF ZF
AF
PF
CF
? = undefined; – = unchanged
–
–
–
–
–
– res – res – res 1
BITS
DW
0100100010001001b
; 4889h
; rotate word, maintaining 1 in low bit
STC
; maintain 1 in low bit: CF = 1
RCL
BITS,1
; BITS = 9113h = 1001000100010011b
; CF = 0
Содержание Am186 Series
Страница 1: ...Am186 and Am188 Family Instruction Set Manual February 1997...
Страница 10: ...Table of Contents x...
Страница 18: ...Programming 1 8...
Страница 40: ...Instruction Set Listing 3 14...