ProDOS #22
Don't Put Parameter Blocks on Zero Page

Written by Dave Lyons (July 1989)

Putting ProDOS 8 parameter blocks on zero page ($00-$FF) is not recommended.

It is not a good idea to put the parameter blocks for ProDOS 8 MLI calls on zero page. This is not forbidden by the ProDOS 8 Technical Reference Manual, but then again, it also doesn't tell you not to put parameter blocks in ROM, in the $C0xx soft switch area, or just below the active part of the stack.

If you do put MLI parameter blocks on zero page, your application may break in the future.

If your parameter block comes between $80 and $FF, it won't work with AppleShare installed.

Further Reference

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