Overview and History
The Amstrad PC1640 was introduced in 1987 as the successor to the PC1512, Amstrad's first IBM PC compatible which had launched in 1986 at just 399 pounds plus VAT. The PC1640 addressed the main limitation of its predecessor by upgrading from 512KB to 640KB of RAM and replacing the CGA-compatible graphics with an EGA-compatible chipset from Paradise Systems. In the US, it was marketed as the PC6400 through Texas-based Vidco Inc., and Schneider sold re-branded versions in Germany.
CGA/MDA Video Adapter Lab - Engineering Application
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
XT-Emporium