Static 16-color background display in Mode 1 (4bpp)
Displays a single full-screen tiled background using Mode 1, the most commonly used SNES video mode. Mode 1 provides two 4bpp layers (BG1 and BG2, each up to 16 colors) plus one 2bpp layer (BG3, 4 colors). This example uses only BG1 with a 16-color tileset and tilemap converted from a PNG by gfx4snes.
This is a direct port of the PVSnesLib "Mode1" example.
- SNES Concepts
- Mode 1: BG1/BG2 are 4bpp (16 colors each), BG3 is 2bpp (4 colors)
- bgInitTileSet() for combined tile + palette loading with VRAM address configuration
- dmaCopyVram() for tilemap data transfer to a separate VRAM region
- VRAM layout: tilemap at $0000, tiles at $4000 (non-overlapping regions)
- Force blank (setScreenOff) during VRAM setup to avoid mid-frame writes
- What to Observe
- A static full-screen image rendered as 8x8 tiles on BG1
- Only BG1 is enabled; BG2 and BG3 are unused
- The image remains stationary (no scrolling)
- Modules Used
- console, sprite, dma, background
- See also
- background.h, dma.h, video.h
Entry point – load a 4bpp tileset and display a static Mode 1 image.
Demonstrates the most common SNES video mode setup: force blank the screen, configure BG1's tilemap and tile base addresses, load tile graphics and palette via bgInitTileSet(), DMA the tilemap to VRAM, select Mode 1, enable BG1, and turn on the screen. The result is a static full-screen tiled image using up to 16 colors.
The VRAM layout places the tilemap at $0000 and tile graphics at $4000 to avoid overlap (each tilemap is up to 2KB, tile data can be many KB).
- Returns
- Never returns (infinite loop).
1.9.8