Looking for Birth Date Place of Robert Armstrong 1600 S

Robert Armstrong married Jenat Scot 12-06-1694 Ettrick Parish, Selkirk County, Scotland.

James Armstrong born 25-12-1697 Ettrick Parish, Selkirk County, Scotland.(Son of Robert & Jenat Armstrong)

Jenat Scot born 03-04-1670 Campbelltown, Argyll, Scotland.(Parents of Jenat were William Scot & Agnes Love)

I have not been able to find the Birth Date/Place of Robert Armstrong in 17th Century Scotland.