You go

dec A sequentially decrementing the content of A

and then if the result reaches zero, you "do something". A lot depends on how "something" ends, doesn't it?

if you simply [edit] OOPS, forgot that one should first leftshift A in some way that doesn't upset the applecart with respect to carry, and then [/edit]

MOV DPTR #tablebase+a
JMP @A+DPTR

in place of all those DEC A lines

doesn't that do what you want with much less hassle, assuming of course that you've built the table correctly? When you insert something, it's immediately correct and complete if you insert it in the correct place. You mentioned that you've already got tables involved. Perhaps that will save some changes there, too. It'll certainly reduce the time consumed, and the uncertainty in the time from loading A to taking appropriate action.

Maybe I'm missing something ... I've got a severe cold and don't see well ... I probably don't think too well either right now.

RE