Do any of you old-timers (e.g. Fairchild, Cole) know how the EDIT (ED)
instruction came to be the way it is? It's one of the original IBM 360
instructions. Has to be the most complicated of them. Did they have
microcode back then?

The main thing that bugs me about this instruction is that if you want
leading zeroes, you have to add a "fix up" instruction at the end, or
prepend an extra zero by means of the fill character. This is because
the significance starter does not turn on the S-trigger for that byte.
Also, the way the fill character is set, where it has to be the first
byte, bugs me.

Why is it like that? It IS a useful instruction, but it's annoying.

Thanks,
Justin

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