There is a set of programs called the Terminal Support System that can be used to customize the interface between an application {or development environment} and its terminal{s}. It consists of several modules that handle echoing, code translation, and other functions.

Programs currently supported are those that assume the terminal is one of the following "virtual terminal types":

3270

3215 {supported through the CP SIO interface}

Asynchronous Ascii {TTY-type} terminals

"Asynchronous" here means input and output can be performed simultaneously.

3270-type, locally attached

Asynchronous Ascii {TTY-type} terminals through Tymnet