VIDEOCHK (1995) by Richard Mewett
A DOS video‑mode detection and diagnostics tool designed to detect, test, and report available video modes on a system.

⭐ Features

• Video Mode Detection
• Scans available BIOS video modes
• Identifies VGA, EGA, CGA, and text modes
• Reports supported resolutions
• Displays mode numbers and attributes
• Screen Mode Testing
• Switches into each detected mode
• Displays test patterns or colour bars
• Verifies rendering stability
• Confirms compatibility for graphics‑based programs

Diagnostic Output

• current mode
• mode number
• resolution
• colour depth

🧩 Technical Notes

• BIOS interrupt 10h (video services)
• Mode numbers 0–13h, 3Dh, 3Eh, 3Fh
• Direct screen writes for test patterns
• Safe restoration of text mode (03h)
• Optional 50‑line mode detection