P60ARM-B/IG/GP1N Zarlink Semiconductor, Inc., P60ARM-B/IG/GP1N Datasheet - Page 24

• Manufacturer Part Number: P60ARM-B/IG/GP1N
• Description: A Low Power, General Purpose 32 Bit RISC Microprocessor
• Manufacturer: Zarlink Semiconductor, Inc.

P60ARM-B
4.2 The Condition Field
All ARM60 instructions are conditionally executed, which means that their execution may or may not take
place depending on the values of the N, Z, C and V flags in the CPSR. The condition encoding is shown in
Figure 6: Condition Codes .
If the always (AL) condition is specified, the instruction will be executed irrespective of the flags. The never
(NV) class of condition codes shall not be used as they will be redefined in future variants of the ARM
architecture. If a NOP is required it is suggested that MOV R0,R0 be used. The assembler treats the absence
of a condition code as though always had been specified.
The other condition codes have meanings as detailed in Figure 6: Condition Codes , for instance code 0000
(EQual) causes the instruction to be executed only if the Z flag is set. This would correspond to the case
where a compare (CMP) instruction had found the two operands to be equal. If the two operands were
different, the compare instruction would have cleared the Z flag and the instruction will not be executed.
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31
Cond
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Condition field
0000 = EQ - Z set (equal)
0001 = NE - Z clear (not equal)
0010 = CS - C set (unsigned higher or same)
0011 = CC - C clear (unsigned lower)
0100 = MI - N set (negative)
0101 = PL - N clear (positive or zero)
0110 = VS - V set (overflow)
0111 = VC - V clear (no overflow)
1000 = HI - C set and Z clear (unsigned higher)
1001 = LS - C clear or Z set (unsigned lower or same)
1010 = GE - N set and V set, or N clear and V clear (greater or equal)
1011 = LT - N set and V clear, or N clear and V set (less than)
1100 = GT - Z clear, and either N set and V set, or N clear and V clear (greater than)
1101 = LE - Z set, or N set and V clear, or N clear and V set (less than or equal)
1110 = AL - always
1111 = NV - never
Figure 6: Condition Codes
0