IBM 2540


The IBM 2540 is a punched-card computer peripheral manufactured by IBM Corporation for use of System/360 and later computer systems. The 2540 was designed by IBM's Data Processing Division in Rochester, Minnesota, and was introduced in 1965. The 2540 could read punched-cards at 1000 cards per minute and punch at 300 CPM. The 2540 was based on the design of the older, slightly slower, 1402.

Description

The 2540 attached to a System/360 multiplexer or selector channel through an IBM 2821 Control Unit. A standard 2540 processed standard IBM 80 column punched cards. The card reader and card punch devices were separately addressable and functioned independently. The 2540 normally read and punched EBCDIC data, called data-mode 1.

Card reader

On the right side of the device was the reader, consisting of an input hopper holding approximately 3100 cards, and three output stackers each holding approximately 1350 cards. Cards could be directed to an output stacker under program control.

Card punch

On the left side of the device was the punch, with an input hopper holding about 1350 cards, and three output stackers each holding 1350. The center stacker was shared between the reader and the punch, but was not intended to be used by both at the same time. Cards could be directed to an output stacker under program control.
The card was read after punching to ensure that the data was punched correctly.

Special features

With the introduction of System/370 IBM announced the improved 3525 card punch and the 3505 card reader in 1971.