Samsung S3F84B8, User Manual

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S3F84B8_UM_REV 1.00 6 INSTRUCTION SET
6-11
6.2.3 CONDITION CODES
The opcode of a conditional jump always contains a 4-bit field called the condition code (cc). This code specifies
the conditions under which the jump is executed. For example, a conditional jump with the condition code for
“equal” after a compare operation only jumps if the two operands are equal.
Table 6-6
lists the condition codes. The carry (C), zero (Z), sign (S), and overflow (V) flags control the operation of
conditional jump instructions.
Table 6-6 Condition Codes
Binary Mnemonic Description Flags Set
0000 F Always false –
1000 T Always true –
0111
(NOTE)
C Carry C = 1
1111
(NOTE)
NC No carry C = 0
0110
(NOTE)
Z Zero Z = 1
1110
(NOTE) NZ Not zero Z = 0
1101 PL Plus S = 0
0101 MI Minus S = 1
0100 OV Overflow V = 1
1100 NOV No overflow V = 0
0110
(NOTE)
EQ Equal Z = 1
1110
(NOTE)
NE Not equal Z = 0
1001 GE Greater than or equal (S XOR V) = 0
0001 LT Less than (S XOR V) = 1
1010 GT Greater than (Z OR (S XOR V)) = 0
0010 LE Less than or equal (Z OR (S XOR V)) = 1
1111
(NOTE) UGE Unsigned greater than or equal C = 0
0111
(NOTE) ULT Unsigned less than C = 1
1011 UGT Unsigned greater than (C = 0 AND Z = 0) = 1
0011 ULE Unsigned less than or equal (C OR Z) = 1
NOTE:
1. It indicates the condition codes related to two different mnemonics that test the same flag. For example, Z and EQ are
both true if zero flag (Z) is set, but after an ADD instruction, Z may be used; however, after a CP instruction, EQ may be
used.
2. For operations involving unsigned numbers, special condition codes like UGE, ULT, UGT, and ULE must be used.