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Table 1.11 Data type modifiers (OP.modifier).
ModifierData Type
BByte (8 bits)
UBUnsigned Byte (8 bits)
HHalf Word (16 bits)
UHUnsigned Half Word (16 bits)
WWord (32 bits)
UWUnsigned Word (32 bits)
FFloating Point (32 bits)
DDouble Precision Floating Point (64 bits)
CCharacter or Decimal in an 8-bit format
PDecimal in a packed (4-bit) format

Table 1.12 Branch conditionsBC.CC.
CCConditionCCCondition
TTrue (always)LELess Than or Equal
FFalse (never)LTLess Than
VOverflowEQEqual
CCarry or BorrowNENot Equal
PEEven ParityGEGreater Than or Equal
POOdd ParityGTGreater Than

Table 1.13 Three conventions used in this book: ALU instruction.
Case 1OP.X Destination, Source 1, Source 2 (three operand format)
or
Case 2OP.X Destination, Source (if only two operands are specified)
or
Case 3OP.X Destination/Source 1, Source 2 (here OP uses two source operands and rewrites the result in the source 1 location)
(OP indicates an ALU operation and X indicates a data type/size. Case 1 is used in L/S machines, case 3 in R/M. The OP type distinguishes case 2 from the others. The R+M machines use all three cases. The formats are distinguished implicity by OP or explicitly by a special OP identifier, e.g., ADD2 or ADD3.)

 
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