Terminal graphics support

There are three modes of graphics support in OS/400 regarding terminals.

GDDM

A subset of the mainframe Graphical Data Display Manager was ported to OS/400.

GDDM needs special support regarding terminals. The only existing twinax terminal supporting GDDM was the 5292 model 2.

Emulators supporting GDDM:

• IBM PC support for DOS (not verified), with special drivers, resolutions up to 1024×768 might be possible,
• an older IDEAcomm release for Windows 3.1 (16 bit), precise version not known.

In later times, it was presumably meant as a way to create graphics for printing.

Enhanced display

This is a function of the 5250 controller in tandem with a hardware terminal, or a feature of the emulator itself. It provides automatic replacement of on-screen objects with a more or less graphical representation of an object. This includes, but is not limited to:

• Window borders
• DDS MLTCHCFLD as check boxes
• DDS SNGCHCFLD as radio buttons
• DDS SFLEND(*SCRBAR) for load-all subfiles

Enhanced display needs special support regarding terminals. It is present at least in the twinax 3486 terminal, but presumably in all 348x terminals.

Emulators supporting Enhanced Display:

• all (newer?) IBM provided 5250 emulators
  • iACS
  • Client Access
• tn5250j (seems to be broken)

APA

All Points Addressable is IBM lingo for pixel graphics support. Little is known about this mode at all, and its sole use case was the dspfax command, to see received Faxes in TIFFG4 format.

According to documentation, the 3489 is the only hardware terminal supporting this display mode.

No known emulators support APA.

See also

• IBM Twinax-Terminals Overview
• Communications Traces

Weblinks

• Application Display Programming (PDF download), IBM.com