Np2-wasm NPM | npm.io

np2-wasm

This is a PC-9801 / PC-9821 emulator based on Neko Project II that runs in a web browser.

Demo

https://irori.github.io/np2-wasm/

Custom Element API

elements.js defines two custom elements, <PC-9801> and <PC-9821>.

Example

The following example embeds a PC-9801 emulator with a CPU clock of 12.5MHz and 2MB of memory into the page, and boots it with image.d88 set in floppy disk drive 1.

<!DOCTYPE html>
<html>
 <body>
  <script src="https://unpkg.com/np2-wasm/dist/elements.js" type="module"></script>
  <!-- Use <PC-9821> instead of <PC-9801> for PC-9821 emulation -->
  <PC-9801 cpu-clock="12.5MHz" memory="2MB" fdd1="image.d88"></PC-9801>
 </body>
</html>

Attributes

`cpu-clock`

Specifies the CPU clock frequency in MHz. You can specify it as 12.5MHz or 12.5, both mean the same.

`memory`

Specifies the memory size in MB. You can specify it as 2MB or 2, both mean the same.

`fdd1`, `fdd2`

Specifies the URL of the disk image to be set in the floppy disk drive. Due to the same-origin policy, disk images from other sites cannot be loaded.

`hdd1`, `hdd2`

Specifies the URL of the disk image to be set in the hard disk drive. Due to the same-origin policy, disk images from other sites cannot be loaded.

`no-mouse`

Disables the mouse and prevents pointer lock when clicked on the emulator screen.

JavaScript API

Example

example.html:

<!DOCTYPE html>
<html>
 <body>
  <canvas id="canvas"></canvas> <!-- The screen will be drawn on this canvas -->
  <script type="module" src="example.js"></script>
 </body>
</html>

example.js:

import { NP2, NP21 } from "https://unpkg.com/np2-wasm/dist/np2-wasm.js";

// Create an NP2 instance specifying a canvas
const canvas = document.getElementById('canvas');
// Change this to NP21.create() if i386 emulation is needed
const np2 = await NP2.create({ canvas });

// Load a floppy disk image
const resp = await fetch('image.d88');
const data = new Uint8Array(await resp.arrayBuffer());
np2.addDiskImage('image.d88', data);

// Set the disk image to FD drive 0
np2.setFdd(0, 'image.d88');

// Run the emulator
np2.run();

Reference

NP2.create(config: NP2Config): Promise\

Creates a new instance of NP2. config is an object that has the following attributes:

canvas: HTMLCanvasElement

The <canvas> element that displays the screen of the emulator.

onDiskChange: (name: string) => void

A callback function that is called when a write operation is performed to the disk image. The modified image can be retrieved with the getDiskImage() method.

onExit: () => void

A callback called when the emulator is powered off. After exit, you can restart the emulator with reset().

clk_base: number (default=2457600)

Specifies the base clock (Hz) of the CPU. Either 1996800 or 2457600 can be specified.

clk_mult: number (default=4)

Specifies the multiplication factor for the CPU. The actual CPU speed will be the product of this value and the base clock.

ExMemory: number (default=1)

Specifies the capacity of the extended memory in MB.

Latencys: number (default=250)

Specifies the output buffer size for the sound emulator in milliseconds. Please specify a number between 20 and 1000 ms. A smaller value will shorten the delay of the sound, but it will require more CPU power.

use_menu: boolean (default=true)

Show the Neko Project II menu on middle-click or F11.

no_mouse: boolean (default=false)

Disables mouse emulation.

NP21.create(config: NP2Config): Promise\

Same as NP2.create(), but this will create an instance of the PC-9821 emulator NP21.

state: 'ready' | 'running' | 'paused' | 'exited'

Returns the current state of the emulator.

run(): void

Starts the emulator.

reset(): void

Resets the emulator.

addDiskImage(name: string, bytes: Uint8Array): void

Adds a disk image to the emulator.

getDiskImage(name: string): Uint8Array

Returns the current content of the disk image.

setFdd(drive: number, name: string | null): void

Sets a disk image to the floppy disk drive of the emulator. drive is the drive number (0 or 1). name is the disk name specified in addDiskImage, or null to eject the disk.

setHdd(drive: number, name: string | null): void

Sets a disk image to the hard disk drive of the emulator. drive is the drive number (0 or 1). name is the disk name specified in addDiskImage, or null to eject the disk. If this method is called after running run(), the effect is not reflected until reset() is called.