nes-emu/ppu/mirroring.js

A NES emulator

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = void 0;
var _memory = require("../memory");
// Name tables A and B are located in 0x000 and 0x400 but can be remapped.

const HORIZONTAL = _memory.RewiredMemoryChunk.createMapping([{
  from: 0x400,
  size: 0x400,
  to: 0x000
},
// top-right (A mirror)
{
  from: 0x800,
  size: 0x400,
  to: 0x400
},
// bottom-left (B)
{
  from: 0xc00,
  size: 0x400,
  to: 0x400
} // bottom-right (B mirror)
]);
const VERTICAL = _memory.RewiredMemoryChunk.createMapping([{
  from: 0x800,
  size: 0x400,
  to: 0x000
},
// bottom-left (A mirror)
{
  from: 0xc00,
  size: 0x400,
  to: 0x400
} // bottom-right (B mirror)
]);
const ONE_SCREEN_LOWER_BANK = _memory.RewiredMemoryChunk.createMapping([{
  from: 0x400,
  size: 0x400,
  to: 0x000
},
// top-right (A mirror)
{
  from: 0x800,
  size: 0x400,
  to: 0x000
},
// bottom-left (A mirror)
{
  from: 0xc00,
  size: 0x400,
  to: 0x000
} // bottom-right (A mirror)
]);
const ONE_SCREEN_UPPER_BANK = _memory.RewiredMemoryChunk.createMapping([{
  from: 0x000,
  size: 0x400,
  to: 0x400
},
// top-left (A mirror)
{
  from: 0x800,
  size: 0x400,
  to: 0x400
},
// bottom-left (A mirror)
{
  from: 0xc00,
  size: 0x400,
  to: 0x400
} // bottom-right (A mirror)
]);
const FOUR_SCREENS = {}; // (the complete 4KB area is available)
var _default = exports.default = {
  HORIZONTAL,
  VERTICAL,
  ONE_SCREEN_LOWER_BANK,
  ONE_SCREEN_UPPER_BANK,
  FOUR_SCREENS
};