>> Off the wall thinking.... is there a prom setting that is used to
>> determine the keyboard type?
> No, the keyboard is asked for [its] type (but if I read the code
> correctly the answer is the same for a type 4 and type 5, only the
> type 5 will send some make/break codes the type 4 never would).

Some post-type-4 Sun keyboards have a bank of DIP switches on the back
that allows you to set what they identify themselves as.  This may
explain part of the confusion here, as I think one of the options
available is to make the keyboard claim to be a type-4.

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