VERA Versatile Embedded Retro Adapter

This is the VERA video card originally by Frank van den Hoef with several improvements; ready to add to your homebrew computer, or as a backup for your Commander X16 or OtterX!

Improvements over original VERA

• All bug fixes and new features added by the X16 project
• Improved routing for better signal integrity
• Sync levels shifted to 5V
• ESD protection on all ports
• Header with SD card port signals for a front-panel SD card
• Digital audio and video header for a future daughterboard with HDMI-compatible output

Standard VERA functionality

Video support

• VGA 640x480
• NTSC Composite
• NTSC S-Video
• NTSC 480i (Composite & S-Video)
• NTSC 240p ("VIC-20" style, composite & S-Video)
• 15KHz RGB ("Amiga" style)

Basic Display

• ~128K of onboard VRAM
• 2 independent display layers
• 1, 2, 4, and 8-bit per pixel color depths
• Bitmap support up to 320x240x8
• Tilemap support for text and other tiled graphics

Sprites:

• Up to 128 sprites
• 8, 16, 32, and 64 pixel widths
• 4- or 8-bit per pixel color depth
• Adjustable Z-depth
• Hardware collision detection

Cool 16-bit-like graphics features

Not quite as good as many 16-bit graphics, but something in between 8-bit era graphics and 16-bit era.

• Line drawing helper
• Polygon fill helper
• Affine transform helper
• Memory fill accelerator
• General purpose 16-bit signed multiply and accumulate function

Audio

Advanced audio that is simultaneously on par with 16-bit systems and less than some 8-bit options:

• 16-voice stereo polyphonic programmable sound generator
• Pulse, sawtooth, triangle, and noise audio waveforms
• No sine waveform
• No volume envelopes
• 8- and 16-bit stereo PCM audio
• Up to 48.8 KHz PCM sample rate

Multiple interrupt sources:

• VSYNC
• Line match interrupt
• Audio FIFO low
• Sprite collision

In progress

Features under development but not yet released. Will be available as a firmware once ready:

• 4-bit ADPCM