Irma board

Irma board, originally spelled IRMA board, refers to a brand of coaxial interface cards for PCs and Macintosh computers used to enable 3270 emulator programs to connect to IBM mainframe computers.

IRMA boards were invented by Technical Analysis Corp. (TAC), acquired by Digital Communications Associates, Inc. (DCA) who manufactured and marketed the Irma products from 1982 on. DCA of Alpharetta, Georgia, was acquired in 1994 by Attachmate Corporation of Bellevue, Washington.

A board with all the capabilities of that which would eventually be called IRMA was originally developed in-house by Amdahl Corp in 1977, but it was not actively marketed by Amdahl.

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