Literals; Evaluation Of Literals - HP 9835A Programming Manual

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Assembly Language Fundamentals
The SET pseudo-instruction defines a symbol in identical fashion to an EQU. Consequently, it
has the same general form -
{label} ~ '::;[T' {expression}
The difference between the two is that the SET instruction can have its {label} be a symbol
which has been previously defined. The effect in that case is to allow a redefinition of the
symbol. For example, after assembling the following instructions -
the symbol "Three" has the value 30B.
Literals
Literals are a special means of defining your own symbols without actually having to go to the
trouble to do so. The result is a form of symbolic addressing without the symbol.
The form of a literal is -
:::: {expression} [, {expression} [,' ...
J J
where {expression} may be any absolute or relocatable expression (see "Expressions" below).
Evaluation of Literals
When a literal is encountered in an operand, three things occur -
1.
The literal is converted to its binary value. If there is more than one expression in the
literal, then they are all converted.
2. The binary value is stored in a literal pool. If there is more than one expression in the
literal, then they are stored contiguously in the order specified.
3. The address of where the value is stored is then substituted for the literal i.n the operand.
If the same literal is used in more than one instruction, only one value is generated in the literal
pool. All instructions using this literal refer to the same location.