Flags – Samsung S3F80JB User Manual
Page 71
CONTROL REGISTERS
S3F80JB
4-4
FLAGS
- System Flags Register
Bit Identifier
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
Zero Flag Bit (Z)
0
Operation result is a non-zero value
1
Operation result is zero
Sign Flag Bit (S)
0
Operation generates positive number (MSB = "0")
1
Operation generates negative number (MSB = "1")
.7
Carry Flag Bit (C)
0
Operation dose not generate a carry or borrow condition
1
Operation generates carry-out or borrow into high-order bit7
.6
.5
Set1
Bank0
Register address
(Bank )
Register address
(Set )
Figure 4-1. Register Description Format