a56 is an assembler for the Motorola DSP56000[?] and DSP56001[?] digital signal processors by Quinn Jensen[?] <jensenq@qcj.icon.com>. Version 1.1 is available from an alt.sources archive or ftp://wuarchive.wustl.edu/.
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This article (or an earlier version of it) contains material from FOLDOC, used with permission.