Correct me if I'm wrong, but the 990's EVENT messages (i.e., "responses") appear to be fixed-length, afterall. I see nothing in the protocol to suggest that anything less than the full complement of 13 text bytes and 11 status bytes are returned in every EVENT message. Hence, the COUNT value should always be 24 (or 18h) and the location of each status bit fixed. Sorta nice.

I haven't received my 990 yet, so can't verify.

Dave