IBM 2821 Control Unit

The IBM 2821 Control Unit was used to attach card readers, card punches and line printers to the IBM System/360 and IBM System/370 families of computers. The devices attached were as follows:

Six models of the IBM 2821 Control Unit were available, as follows:

IBM (November 1969). IBM 2821 Component Description (PDF). Eighth Edition. A24-3312-7. 

IBM (October 1982). IBM 2821 Component Description (PDF). Tenth Edition. GA24-3312-9. 

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