HLASM: V1R6 Language Ref

DC instruction—Hexadecimal floating-point constantsType │ Called │ Format─────┼────────────┼────────────────────────────────────────────────────────────────E │ Short │ ▌1▐ 7-bit Characteristic ▌2▐ 24-bit FractionEH │ Floating- │ ▌3▐ + ┌──────────┴──────────┐ ┌────────────┴────────────┐│ Point │ │ ┌───┬─────────────────────┐ ┌───────────/ /───────────┐│ Number │ └► └───┴─────────────────────┘ └───────────/ /───────────┘│ │ −│ │ Bits 0 1 7 8 31││││││D │ Long │ 7-bit Characteristic 56-bit FractionDH │ Floating- │ + ┌──────────┴──────────┐ ┌────────────┴────────────┐│ Point │ ┌───┬─────────────────────┐ ┌───────────/ /───────────┐│ Number │ └───┴─────────────────────┘ └───────────/ /───────────┘│ │ −│ │ Bits 0 1 7 8 63│││││││ │ High-order 56 bitsL │ Extended │ 7-bit Characteristic of 112-bit FractionLH │ Floating- │ + ┌──────────┴──────────┐ ┌────────────┴────────────┐LQ │ Point │ ┌───┬─────────────────────┐ ┌───────────/ /───────────┐│ Number │ └───┴─────────────────────┘ └───────────/ /───────────┘───┐│ │ − ││ │ Bits 0 1 7 8 63 ││ │ ││ │ ┌─────────────────────────────┘│ │ ││ │ │ Low-order 56 bits│ │ 7-bit Characteristic of 112-bit Fraction│ │ + ┌──────────┴──────────┐ ┌────────────┴────────────┐│ │ ┌───┬─────────────────────┐ ┌───────────/ /───────────┐│ │ └───┴─────────────────────┘ └───────────/ /───────────┘│ │ − │ │ Bits 0 1 │ 7 8 63│ │ ││ │ Set in second half│ │ of L-type constantCharacteristic │ Hexadecimal Fraction──────────────────┼──────────────────────────────────│ ▌4▐│ a b c▌5▐ 16 E X [ ─── + ─── + ─── + ... ]│ 16 16² 16³│where a,b,c ... are hexadecimal digits, and E is an exponent that has a positive or negativevalue indicated by the characteristicFigure 19. Hexadecimal floating-point external formatsRepresentation of hexadecimal floating point: The assembler assembles afloating-point constant into its binary representation as follows: The specifiednumber, multiplied by any exponents, is converted to the required two-part format.The value is translated into:v A fractional portion represented by hexadecimal digits and the sign indicator.The fraction is then entered into the leftmost part of the fraction field of theconstant (after rounding).Chapter 5. Assembler instruction statements 163