Motorola M68EVB912B32, User Manual

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OPERATION
68EVB912B32UM/D 3-52
<Register Name> Modify Register Value <Register Name>
syntax:
<RegisterName> <RegisterValue>
where:
<RegisterName> is one of the CPU12 registers listed in Table 3-3.
<RegisterValue> is an 8- or 16-bit hexadecimal number.
Table 3-3. CPU12 Registers
Register Name Description Legal Range
PC Program Counter $0 to $FFFF
SP Stack Pointer $0 to $FFFF
X X-Index Register $0 to $FFFF
Y Y-Index Register $0 to $FFFF
A A Accumulator $0 to $FF
B B Accumulator $0 to $FF
D D Accumulator (A:B) $0 to $FFFF
CCR Condition Code Register $0 to $FF
Each of the fields in the Condition Code Register (CCR) may be modified by using the bit names
in Table 3-4.
Table 3-4. Condition Code Register Bits
CCR Bit Name Description Legal Values
S STOP Enable 0 or 1
H Half Carry 0 or 1
N Negative Flag 0 or 1
Z Zero Flag 0 or 1