The IBM 2790 Data Communications System is a family of devices intended for "in-plant data communications and production monitoring."
It is described as a two-way data communications system designed to accommodate large volumes of short messages from many in-plant locations or from smaller groups of terminals at remote locations.
The 2790 consists of the following components, all connected by a two-wire loop operating at 500 kbit/s. The 2715 can support up to 32 KB of magnetic core memory with a 1.2 μs cycle time, an internal disk for microcode load, a 2740 printer/keyboard, and a real time clock.
Firstly it consists of one IBM 2715 Transmission Control Unit, which controls the other system components. The 2715 provides terminal control, transaction assembly, data-entry checking, message routing, transaction storage, and transfer of data to and from a System/370,
IBM 1800 Data Acquisition and Control System or an
IBM System/7
The IBM System/7 was a computer system designed for industrial control, announced on October 28, 1970 and first shipped in 1971. It was a 16-bit machine and one of the first made by IBM to use novel semiconductor memory, instead of magnetic core m ...
.
* 2715 Model 1: Used for local operation
*2715 Model 2: Used for remote attachment with a binary synchronous communication adapter such as a
270x 270x is a generic name for a family of IBM non-programmable communications controllers used with System/360 and System/370 computers.
The family consisted of the following devices:
* IBM 2701 Data Adapter Unit
* IBM 2702 Transmission Control
* I ...
communications controller.
There are numerous data entry devices that can be attached:
* The IBM 2791 Area Station is a tabletop unit attached to the 2790 loop. The 2791 can read ten column identification badges and eighty column punched cards, and has a twelve key pad for direct entry of numeric data. The 2791 can attach up to thirty-two 2795/2796 data entry units, a 1053 printer, up to three 1035 remote badge readers, and an OEM device. The 2791 has nine user defined "transaction buttons". Up to 100 2791/2793 can be attached.
* The IBM 2793 Area Station is similar, but lacks the ability to accept input data directly. It can attach up to thirty-two data entry units and a 1053 printer. Up to 100 2791/2793 can be attached.
* The IBM 2795, 2796 and 2797 Data Entry Units are compact industrial units for reporting job and machine status and production information.
Both have two ten-position switches and a ten column badge reader. The 2796 has an additional two switches and allows for manual entry of up to four digits.
*2740 Communications Terminal (one)
*2798 Guided Display Units. This is a versatile and compact data entry and output unit with a 56 character keyboard, 8 control keys and 16 position visual display. Up to 12 can be attached.
References
2790
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