What's the purpose of address $29E?

["Dennis Debro" <dennis@xxxxxxxxxxxxxxx>]

Hi there,

What is $29E used for?

In Spitfire Attack they do...

   lda #$20
   sta $029E

and

   lda #$22
   sta $029E

Could these be accessing the NUSIZx registers?

BTW, thanks Eckhard for answering my question about the $288 address. I
looked at Jawbreaker again and yes this is the same as SWCHA. How does
that work? Am I missing something? These addresses don't show in any
documentation I have.

Take care,
Dennis