Giulio / ceda-schematics - History

Schematics refactoring:

- New sheet reserved to video memory.
- Removed video memory parts inside video_generation.
- Removed video memory parts inside GPIO.
- Generic cleanup to keep all circuits inside each sheet.

Discovered WE and OE signals for video memories, plus others

Video memory concurrency

- bank7 selector to address video or attribute RAM
- found read and write data paths leading to video RAMs (F11, F12).
- video RAMs CS generation.

Other steps in video generation

- Some notes regarding video attributes.
- Found some stuck-at inputs.

A long job in analog video output

! Read comments inside video_memory_management sheet for more
informations.

- Completed path between dot pattern output of character shift register
and beam output transistor.
- Found behavior of video attribute signals: blink, underline, stretch,
hide.
- Completed wiring of 28L22 ROM, which is involved in video attributes.
- TODO: video_memory_management must be cleaned up, since schematics has grown
outside sheet.

Discovered bank 0 + fixed wrong signals in video gen