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SNROM template

This is a minimal working program for the Nintendo Entertainment System using the SGROM, SNROM, UNROM, or UOROM board. It assumes familiarity with nrom-template.

Additional concepts illustrated:

initializing the MMC1
loading tile data into CHR RAM
calls from one PRG bank to another

Setting up the build environment

Building this demo requires cc65, Python, Pillow, GNU Make, and GNU Coreutils. For detailed instructions to set up a build environment, see nrom-template.

Organization of the program

Include files

nes.inc: Register definitions and useful macros
global.inc: Global variable and function declarations

Source code files

mmc1.s: iNES header and driver for MMC1
unrom.s: iNES header and driver for UNROM/UOROM
init.s: PPU and CPU I/O initialization code
main.s: Main program
bankcalltable.s: List of entry points called through a far call (one that goes from one bank to another)
chrram.s: CHR RAM data setup
bg.s: Background graphics setup
player.s: Player sprite graphics setup and movement
pads.s: Read the controllers in a DPCM-safe manner
ppuclear.s: Useful subroutines for interacting with the S-PPU

Greets

NESdev Wiki and forum contributors
FCEUX team
Joe Parsell (Memblers) for getting me into NESdev in the first place
Jeremy Chadwick (koitsu) for more code organization tips

Legal

The demo is distributed under the following license, based on the GNU All-Permissive License:

Copyright 2011-2016 Damian Yerrick

Copying and distribution of this file, with or without modification, are permitted in any medium without royalty provided the copyright notice and this notice are preserved in all source code copies. This file is offered as-is, without any warranty.