LIM 4.0 focused EMS board and backplane line for pre-386 platforms, designed for deterministic page-frame mapping and predictable software compatibility.

Standard

LIM EMS 4.0 page-frame compatibility

Frame Windows

D000h and E000h profile sets

Capacity Range

2MB to 8MB banked architecture

Configuration

Register maps with conflict-safe presets

Validation Suite

Lotus 1-2-3, QEMM, DOS extender scenarios

Deployment Form

Single-card and modular backplane builds

Restoration and validation workflow for monochrome and color text-era adapters, including monitor timing and character ROM behavior.

Adapter Modes

MDA, Hercules-compatible, CGA text and graphics

Output Paths

TTL monochrome, composite, RGBI output checks

Clock Profiles

14.31818MHz domain checks and divider validation

ROM Handling

Character ROM preservation and checksum workflow

Display Validation

Geometry, sync, and phosphor persistence tests

Field Scope

Pre-286 display stack bring-up and troubleshooting