A Programmable Data Concentrator for a Large Computing System

摘要

Most large time sharing computers require some sort of a data concentrator or multiplexer to accept inputs from a large number of low speed remote terminals. Two major disadvantages of most of these concentrators are that they are non-programmable and relatively expensive. This paper describes the use of a small micro-programmed computer with a special instruction wired into the Read Only memory to perform the multiplexing action. This approach has resulted in a programmable terminal controller which will handle up to 32 remotes and provides enough processing capability to do code conversion and editing. This not only relieves the main computer of these routine tasks, but also reduces the amount and complexity of system modification within the main computer. A dual processor system with a common memory is also proposed. This system will handle sixty-four low speed lines and four 2400 baud lines yet will have 15 times the processing power of the previous system. This will allow more sophisticated pre-processing, such as syntax checking in addition to the code conversion and editing. The cost of this system is less than that of some currently available non-programming terminal controllers that will handle a similar number of lines. (Author)