archive.org's DG collection has Single User BASIC and Extended BASIC manuals, but no BB manual. Does anyone have a PDF?
The underlying question... the earliest mention of BB I can find is from a 1977 ComputerWorld article announcing its release. This includes some rather confusing language about a "double-precision integer arithmetic facility". "double precision" and "integer" are not normally seen in the same statement.
It also states that it was based on the same "research" as Extended BASIC. Extended BASIC includes a complete FP system, and FP libraries and/or hardware are a standard part of DG systems of the era.
I strongly suspect they are actually referring to a BCD or fixed-point system. I find it difficult to believe that any business-oriented language would not have some way to handle pennies, especially considering they include output formatting for dollar formats.
Can anyone shed some light on this?