3270 models

From The x3270 Wiki

The x3270 family can emulate any of the following IBM 3270 models:

3270 Model Description
3278 Monochrome (green-screeen)
3279 Color

Within the above types, there are a number of variants based on screen size:

3270 Model Rows Columns
2 24 80
3 32 80
4 43 80
5 27 132

Extended data stream support

In addition, there is a -E suffix that indicates support for the 3270 Extended Data Stream.

Default and alternate screen sizes

Models 3, 4 and 5 also implicitly emulate a model 2 as well. This is known as the default screen size. When the host sends an Erase/Write command, it sets the terminal to the default screen size. When it sends an Erase/Write Alternate command, it sets the terminal to the alternate screen size (the size listed in the table above).

Some hosts also allow the screen to be larger than the alternate size. This is configured through the oversize resource.

Examples

Color display, 43 rows, 80 columns, extended data stream:

3279-4-E

Monochrome display, 24 rows, 80 columns, no extended data stream:

3278-2