IBM 8100 DPPX

DPPX was written in Programming Language for Distributed Systems (PL/DS), a PL/I-derived systems programming language, similar to the PL/S systems programming language used for MVS and VM. Part of the DPPX/370 development process was developing a PL/DS 2 language, which was based on PL/DS, but with changes necessitated by the changed instruction set. (PL/DS, like PL/S, is a high-level language which encourages significant use of inline assembly.)