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excerpt: "I'm enclosing an article I wrote for S.U.N. last year which never got published. Feel free to doctor it or use it in any way you like. As we have all heard many times, machine language is good for doing things much much faster than BASIC. If any of you have wondered just what real…"
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---

# LDIR Demonstration Program

I’m enclosing an article I wrote for S.U.N. last year which never got published. Feel free to doctor it or use it in any way you like.

As we have all heard many times, machine language is good for doing things much much faster than BASIC. If any of you have wondered just what real applications it might apply to here is a very useful application of a machine subroutine. The routine is based on a Z80 instruction call LDIR.