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ALTOASM 2 October 1974 1




ALTOASM




This assembler, written in BCPL, runs on the Alto and produces BCPL-
compatihle relocatab1e binary output files, suitable for input to BLDR,
the BCPL loader. The source language of this assembler is patterned
after that of the Data General NOVA DOS assembler (see document 093-
000017-02). Additions, deletions, and incompatibilities are described
below.


1. Symbols


Symbols may be up to 130 characters in length, and every character of a
symbol must be used to identify it. By default upper- and lower-case
characters are different, and two character strings represent the same
symbol only if the same letters and cases are used in both. However,
the /U switch causes all lower-case letters in symbols to be changed to
upper case (even in external symbols). Thus if you want an assembly-
language program to link to symbols containing lower-case letters, you
must either default lower-case conversion in ALTOASM or map all symbols
to upper case in BLDR using its /U switch.


2. Strings

Strings follow BCPL conventions. They may not extend from one line to
the next.



3. Omitted Pseudo-operations

The following have been omitted: .TXTO, .TXTE, .TXTF