If (condition true) then PC + d -->; PC
Compatibility: 68000 Family
Attributes: Size = (Byte, Word, Long*)
*(MC68020, MC68030, MC68040 only)
Description: If the specified condition is true, program exe-
cution continues at location (PC) + displacement. The PC
contains the address of the instruction word of the Bcc
instruction plus two. The displacement is a twos compliment
integer that represents the relative distance in bytes from the
current PC to the 16-bit displacement (the word immediately
following the instruction) is used. If the 8-bit displacement
field in the instruction word is all ones ($FF), the 32-bit
displacement (long word immediately following the inst-
ruction) is used. Condition code cc specifies one of the
greater or equal
N ¥ V + /N ¥ /V
N ¥ V ¥ /Z + /N ¥ /V ¥ /Z
/C ¥ /Z
less or equal
Z + N ¥ /V + /N ¥ V
low or same
C + Z
N ¥ /V + /N ¥ V
\i3-++-4Condition,88-bit Displacement,016-bit Displacement if 8-bit Displacement = $00,032-bit Displacement if 8-bit Displacement = $FF,
Instruction Fields (Register Shifts):
Condition field -- The binary code for one of the
conditions listed in the table.
8-bit Displacement field -- Twos complement integer
specifying the number of bytes between the branch
instruction and the next instruction to be executed
if the condition is met.
16-bit Displacement field -- Used for the displacement when
the 8-bit displacement field contains $00.
32-bit Displacement field -- Used for the displacement when
the 8-bit displacement field contains $FF.
Note: A branch to the immediately following instruction auto-
matically uses the 16-bit displacement format because
the 8-bit displacement field contains $00 (zero offset).