364 Cyber EMBEDDEDINN
364 : Cyber EMBEDDEDINN
- Author: Vysakh P Pillai
- Description: VGA Bouncing Text with Generative Font.
- GitHub repository
- Open in 3D viewer
- Clock: 25175000 Hz
Cyber EMBEDDEDINN - VGA Bouncing Text
A single-tile VGA design for Tiny Tapeout featuring bouncing "EMBEDDEDINN" text with a parallax starfield background.
Key Features: Procedural font generation, 640x480 @ 60Hz VGA output, animated starfield.
What it does
This project generates a 640x480 @ 60Hz VGA output displaying animated bouncing text with a dynamic starfield background. The design uses procedurally generated fonts (no ROM required) and creates a retro-style visual effect perfect for demonstrations.
How it works
VGA Timing Generator
The design implements standard VGA 640x480 @ 60Hz timing using a state machine that tracks horizontal and vertical pixel positions. It generates HSYNC and VSYNC signals according to the VGA specification.
Generative Font Engine
Characters are generated using combinational logic that defines primitive shapes (bars, corners) and combines them to form letters. Each character occupies a 32x40 pixel slot, and the text "EMBEDDEDINN" is rendered by selecting appropriate shape primitives based on the current character index.
Animation System
A frame counter synchronized to VSYNC drives the animation. The text position (tx, ty) updates each frame based on a selectable speed. The text bounces off screen boundaries, creating smooth, stable motion.
Interactive Controls
The design features interactive controls via the ui_in pins:
- Speed Control (
ui_in[1:0]):00: Normal speed01: Fast speed (2x)10: Slow speed (0.5x)11: Pause animation
- Color Palettes (
ui_in[3:2]):00: Classic (Deep Blue/Purple)01: Cyberpunk (Neon Pink/Cyan)10: Forest (Green/Emerald)11: Monochrome (Grayscale)
- Scanline Toggle (
ui_in[4]): Toggle the retro scanline effect (OFF when pin is high).
Parallax Starfield
The background features a two-layer parallax starfield created using XOR patterns that change with the frame counter, giving a sense of depth and motion.
Color Mixing
The design outputs 2-bit color (4 levels) for red, green, and blue channels. Text and background colors are adjustable via the interactive controls.
How to test
Connect the TinyVGA PMOD to the output pins and a VGA monitor. The design will automatically start displaying bouncing text.
- Expected output: Bouncing "EMBEDDEDINN" text with parallax starfield
- Controls: Toggle
ui_inpins to change speed, colors, and scanlines. - Timing: 640x480 @ 60Hz (25.175 MHz pixel clock)
- Inputs:
ui_in[1:0]speed,ui_in[3:2]palette,ui_in[4]scanline toggle
The cocotb tests verify:
- VGA timing compliance (HSYNC/VSYNC periods)
- Proper frame generation
- Color output during active video regions
External hardware
- TinyVGA PMOD (mole99/tiny-vga)
- VGA monitor supporting 640x480 @ 60Hz
- VGA cable
The TinyVGA PMOD provides the necessary resistor DAC for 2-bit RGB output and VGA connector.
IO
| # | Input | Output | Bidirectional |
|---|---|---|---|
| 0 | Speed Sel 0 | R1 | |
| 1 | Speed Sel 1 | G1 | |
| 2 | Palette Sel 0 | B1 | |
| 3 | Palette Sel 1 | VSync | |
| 4 | Scanline Toggle | R0 | |
| 5 | G0 | ||
| 6 | B0 | ||
| 7 | HSync |