The 3800 graphic character modification module is variable length and contains up to 64 segments. Each segment contains the 1 byte (for the 3800 Model 1) or 6 bytes (for the 3800 Model 3) of descriptive information and the 72-byte (for the 3800 Model 1) or 120-byte (for the 3800 Model 3) scan pattern of a graphic character.

The graphic character modification module is created using the INCLUDE, GRAPHIC, OPTION and NAME utility control statements.

The INCLUDE statement identifies an existing graphic character modification module that is to be copied and used as a basis for the new module.

To create graphic character modification modules in the syntax of the 3800 Model 3 compatibility mode module, the OPTION statement with the DEVICE parameter is required.

A GRAPHIC statement, when followed by one or more data statements, defines a user-designed character. A GRAPHIC statement can also select a character segment from another graphic character modification module. Each GRAPHIC statement causes a segment to be created for inclusion in the new module.

The NAME statement identifies the new module and indicates that the module is to be added to the library or is to replace an existing module of the same name. More than one GRAPHIC statement can be coded between the INCLUDE and NAME statements, and all such GRAPHIC statements apply to the same graphic character modification module.