Locally attached 3270-type terminals are supported. They can be operated in two modes, line and screen.

In screen mode, the full capabilities of the 3270 terminal are available to the application program.

In line mode, the 3270 is used to emulate an ASCII TTY-type terminal.

When any PF key or Enter is pressed, the data in the input area is read and the input area is cleared. The cursor position is ignored. These program attention keys have the following special effects:
Enter
Add carriage return to the input stream after the data in the input area.

PF1
Translate the last character in the input area to a control character. The translation is:
A-Z translate to control-A through control-Z

a-z translate to control-A through control-Z

@ translates to NUL

[ translates to ESC

\ translates to FS

| translates to GS

]
translates to RS

_ translates to US

If there is no character in the input area, ESC is generated.

PF2
Serves only to transmit the input area.

PF3
Add DEL to the input stream after the data in the input area.

PF6
Retrieve an input line from a buffer. Each time an input line is entered, it is saved in a circular buffer. The number of lines in the buffer depends on their length, but there is always room for one full length line. Lines which are not displayed in the input area (e.g. passwords) are not saved, and empty lines are not saved. Each time PF6 is pressed, the next line is retrieved from the buffer.

PF10
Add control-T to the input stream after the data in the input area.

PF11
Add question mark to the input stream after the data in the input area.

PA1
Generates ESC in the input stream.

PA2
Serves only to allow the screen contents to scroll off the top.

CLEAR
Clears lines off the top of the display.

Thus, all 128 ASCII characters can be generated.