CONTROL REGISTERS S3C9228/P9228
4-4
FLAGS - System Flags Register
.7
.6
.5

Bit Identifier

RESET RESET Value

Read/Write

R = Read-only
W = Write-only
R/W = Read/write
' - ' = Not used
Bit number:
MSB = Bit 7
LSB = Bit 0
Addressing mode or
modes you can use to
modify register values
Description of the
effect of specific
bit settings
RESET value notation:
'-' = Not used
'x' = Undetermind value
'0' = Logic zero
'1' = Logic one
Bit number(s) that is/are appended to the
register name for bit addressing
D5H
Register address
(hexadecimal)
Full Register name
Register
mnemonic
Name of individual
bit or bit function
.7 .6 .5 .4 .2.3 .1 .0
x
R/W x
R/W x
R/W
x
R/W 0
R/W
x
R/W 0
R/W
x
R/W
Carry Flag (C)
0Operation dose not generate a carry or borrow condition
1Operation generates carry-out or borrow into high-order bit7
Zero Flag
0Operation result is a non-zero value
1Operation result is zero
Sign Flag
0Operation generates positive number (MSB = "0")
1Operation generates negative number (MSB = "1")

Figure 4-1. Register Description Format