The deal is expected to close in May.
Under the agreement, ComStream's Hi-Media broadband communications division will be folded into Rockwell's newly formed Digital Infotainment division, part of its Semiconductor Systems business.
The Infotainment division will include the modem communications products used in digital set-top boxes and Internet access terminals, as well as the graphics and video business units of Brooktree, which Rockwell acquired last year.
Forming the division is part of Rockwell's transition from the declining defense industry to the electronics market.
A.C. D'Augustine, the former general manager of the Brooktree Division's Graphics and Imaging business unit, was named vice president and general manager of the new division.