Flags — System Flags Register: D5H, Bank0 - Samsung S3F84B8 User Manual

S3F84B8_UM_REV 1.00
4.1.11 FLAGS — SYSTEM FLAGS REGISTER: D5H, BANK0
Bit Identifier
Reset Value
Read/Write
Addressing Mode
.7
.6
.5
.4
.3
.2
.1
.0
.7 .6
x x
R/W R/W
Register addressing mode only
Carry Flag (C)
0 Operation does not generate a carry or borrow condition.
1 Operation generates a carry or borrow into high-order bit 7.
Zero Flag (Z)
0 Operation results in a non-zero value.
1 Operation results in zero value.
Sign Flag (S)
0 Operation generates a positive number (MSB = "0").
1 Operation generates a negative number (MSB = "1").
Overflow Flag (V)
Operation result is  +127 and > -128.
0
1 Operation result is > +127 or < -128.
Decimal Adjust Flag (D)
0 Completes Add operation.
1 Completes Subtraction operation.
Half-Carry Flag (H)
0 No carry-out of bit 3 or no borrow into bit 3 by addition or subtraction.
1 Addition generated carry-out of bit 3 or subtraction generated borrow into bit 3.
Fast Interrupt Status Flag (FIS)
0 Interrupt return (IRET) in progress (when read).
1 Fast interrupt service routine in progress (when read).
Bank Address Selection Flag (BA)
0 Bank 0 is selected.
1 Bank 1 is selected.
.5 .4
x x
R/W R/W R/W
4-14
4 CONTROL REGISTERS
.3 .2 .1
x x 0
R/W R
.0
0
R/W