initial commit

.gitignore

@@ -0,0 +1 @@
+/node_modules/

README.md

@@ -0,0 +1,26 @@
+# @notweb/i2c
+
+I2C access with Node.js
+
+## Usage
+
+```js
+const { requestI2CAccess } = require("@notweb/i2c");
+
+const ADT7410_ADDR = 0x48;
+
+async function main() {
+  const i2cAccess = await requestI2CAccess();
+  const port = gpioAccess.ports.get(1);
+  const i2cSlave = await port.open(ADT7410_ADDR);
+  const temperature =
+    (((await i2cSlave.read8(0x00)) << 8) + (await i2cSlave.read8(0x01))) / 128;
+  console.log(`Temperature: ${temperature} ℃`);
+}
+
+main();
+```
+
+## Document
+
+[Web I2C API](http://browserobo.github.io/WebI2C)

index.d.ts

@@ -0,0 +1,32 @@
+declare type PortNumber = number;
+declare type PortName = string;
+declare type I2CSlaveAddress = number;
+export declare class I2CAccess {
+    private readonly _ports;
+    constructor(ports?: I2CPortMap);
+    readonly ports: I2CPortMap;
+}
+/**
+ * Different from Web GPIO API specification.
+ */
+export declare class I2CPortMap extends Map<PortNumber, I2CPort> {
+    getByName(portName: PortName): I2CPort | undefined;
+}
+export declare class I2CPort {
+    private readonly _portNumber;
+    constructor(portNumber: PortNumber);
+    readonly portNumber: number;
+    readonly portName: string;
+    open(slaveAddress: I2CSlaveAddress): Promise<I2CSlaveDevice>;
+}
+export interface I2CSlaveDevice {
+    readonly slaveAddress: I2CSlaveAddress;
+    read8(registerNumber: number): Promise<number>;
+    read16(registerNumber: number): Promise<number>;
+    write8(registerNumber: number, value: number): Promise<number>;
+    write16(registerNumber: number, value: number): Promise<number>;
+}
+export declare class OperationError extends Error {
+}
+export declare function requestI2CAccess(): Promise<I2CAccess>;
+export {};

index.js

@@ -0,0 +1,66 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+const i2c_bus_1 = require("i2c-bus");
+const I2CPortMapSizeMax = 32;
+const Uint16Max = 65535;
+function parseUint16(string) {
+    const n = Number.parseInt(string, 10);
+    if (0 <= n && n <= Uint16Max)
+        return n;
+    else
+        throw new RangeError(`Must be between 0 and ${Uint16Max}.`);
+}
+class I2CAccess {
+    constructor(ports) {
+        this._ports = ports == null ? new I2CPortMap() : ports;
+    }
+    get ports() {
+        return this._ports;
+    }
+}
+exports.I2CAccess = I2CAccess;
+/**
+ * Different from Web GPIO API specification.
+ */
+class I2CPortMap extends Map {
+    getByName(portName) {
+        const matches = /^i2c-(\d+)$/.exec(portName);
+        return matches == null ? undefined : this.get(parseUint16(matches[1]));
+    }
+}
+exports.I2CPortMap = I2CPortMap;
+class I2CPort {
+    constructor(portNumber) {
+        this._portNumber = parseUint16(portNumber.toString());
+    }
+    get portNumber() {
+        return this._portNumber;
+    }
+    get portName() {
+        return `i2c-${this.portNumber}`;
+    }
+    async open(slaveAddress) {
+        const bus = await i2c_bus_1.openPromisified(this.portNumber).catch(error => {
+            throw new OperationError(error);
+        });
+        return {
+            slaveAddress,
+            read8: cmd => bus.readByte(slaveAddress, cmd),
+            read16: cmd => bus.readWord(slaveAddress, cmd),
+            write8: (cmd, byte) => bus.writeByte(slaveAddress, cmd, byte),
+            write16: (cmd, word) => bus.writeWord(slaveAddress, cmd, word)
+        };
+    }
+}
+exports.I2CPort = I2CPort;
+class OperationError extends Error {
+}
+exports.OperationError = OperationError;
+async function requestI2CAccess() {
+    const ports = new I2CPortMap([...Array(I2CPortMapSizeMax).keys()].map(portNumber => [
+        portNumber,
+        new I2CPort(portNumber)
+    ]));
+    return new I2CAccess(ports);
+}
+exports.requestI2CAccess = requestI2CAccess;

index.ts

@@ -0,0 +1,90 @@
+import { openPromisified } from "i2c-bus";
+
+const I2CPortMapSizeMax = 32;
+
+const Uint16Max = 65535;
+
+function parseUint16(string: string) {
+  const n = Number.parseInt(string, 10);
+  if (0 <= n && n <= Uint16Max) return n;
+  else throw new RangeError(`Must be between 0 and ${Uint16Max}.`);
+}
+
+type PortNumber = number;
+type PortName = string;
+
+type I2CSlaveAddress = number;
+
+export class I2CAccess {
+  private readonly _ports: I2CPortMap;
+
+  constructor(ports?: I2CPortMap) {
+    this._ports = ports == null ? new I2CPortMap() : ports;
+  }
+
+  get ports() {
+    return this._ports;
+  }
+}
+
+/**
+ * Different from Web GPIO API specification.
+ */
+export class I2CPortMap extends Map<PortNumber, I2CPort> {
+  getByName(portName: PortName) {
+    const matches = /^i2c-(\d+)$/.exec(portName);
+    return matches == null ? undefined : this.get(parseUint16(matches[1]));
+  }
+}
+
+export class I2CPort {
+  private readonly _portNumber: PortNumber;
+
+  constructor(portNumber: PortNumber) {
+    this._portNumber = parseUint16(portNumber.toString());
+  }
+
+  get portNumber() {
+    return this._portNumber;
+  }
+
+  get portName() {
+    return `i2c-${this.portNumber}`;
+  }
+
+  async open(slaveAddress: I2CSlaveAddress): Promise<I2CSlaveDevice> {
+    const bus = await openPromisified(this.portNumber).catch(error => {
+      throw new OperationError(error);
+    });
+
+    return {
+      slaveAddress,
+      read8: cmd => bus.readByte(slaveAddress, cmd),
+      read16: cmd => bus.readWord(slaveAddress, cmd),
+      write8: (cmd, byte) => bus.writeByte(slaveAddress, cmd, byte),
+      write16: (cmd, word) => bus.writeWord(slaveAddress, cmd, word)
+    };
+  }
+}
+
+export interface I2CSlaveDevice {
+  readonly slaveAddress: I2CSlaveAddress;
+
+  read8(registerNumber: number): Promise<number>;
+  read16(registerNumber: number): Promise<number>;
+  write8(registerNumber: number, value: number): Promise<number>;
+  write16(registerNumber: number, value: number): Promise<number>;
+}
+
+export class OperationError extends Error {}
+
+export async function requestI2CAccess(): Promise<I2CAccess> {
+  const ports = new I2CPortMap(
+    [...Array(I2CPortMapSizeMax).keys()].map(portNumber => [
+      portNumber,
+      new I2CPort(portNumber)
+    ])
+  );
+
+  return new I2CAccess(ports);
+}

package.json

@@ -0,0 +1,25 @@
+{
+  "name": "@notweb/i2c",
+  "version": "0.0.1",
+  "description": "I2C access with Node.js",
+  "main": "index.js",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/kou029w/notweb-i2c.git"
+  },
+  "author": "Kohei Watanabe <kou029w@gmail.com>",
+  "license": "MIT",
+  "publishConfig": {
+    "access": "public"
+  },
+  "dependencies": {
+    "i2c-bus": "^5.1.0"
+  },
+  "devDependencies": {
+    "@types/node": "^12.7.12",
+    "typescript": "^3.6.4"
+  },
+  "scripts": {
+    "build": "tsc"
+  }
+}

tsconfig.json

@@ -0,0 +1,17 @@
+{
+  "compilerOptions": {
+    "target": "esnext",
+    "module": "commonjs",
+    "moduleResolution": "node",
+    "declaration": true,
+    "noImplicitThis": true,
+    "alwaysStrict": true,
+    "strictBindCallApply": true,
+    "strictNullChecks": true,
+    "strictFunctionTypes": true,
+    "strictPropertyInitialization": true,
+    "noImplicitReturns": true,
+    "noUnusedLocals": true,
+    "noUnusedParameters": true
+  }
+}

yarn.lock

@@ -0,0 +1,38 @@
+# THIS IS AN AUTOGENERATED FILE. DO NOT EDIT THIS FILE DIRECTLY.
+# yarn lockfile v1
+
+
+"@types/node@^12.7.12":
+  version "12.7.12"
+  resolved "https://registry.yarnpkg.com/@types/node/-/node-12.7.12.tgz#7c6c571cc2f3f3ac4a59a5f2bd48f5bdbc8653cc"
+  integrity sha512-KPYGmfD0/b1eXurQ59fXD1GBzhSQfz6/lKBxkaHX9dKTzjXbK68Zt7yGUxUsCS1jeTy/8aL+d9JEr+S54mpkWQ==
+
+bindings@^1.5.0:
+  version "1.5.0"
+  resolved "https://registry.yarnpkg.com/bindings/-/bindings-1.5.0.tgz#10353c9e945334bc0511a6d90b38fbc7c9c504df"
+  integrity sha512-p2q/t/mhvuOj/UeLlV6566GD/guowlr0hHxClI0W9m7MWYkL1F0hLo+0Aexs9HSPCtR1SXQ0TD3MMKrXZajbiQ==
+  dependencies:
+    file-uri-to-path "1.0.0"
+
+file-uri-to-path@1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/file-uri-to-path/-/file-uri-to-path-1.0.0.tgz#553a7b8446ff6f684359c445f1e37a05dacc33dd"
+  integrity sha512-0Zt+s3L7Vf1biwWZ29aARiVYLx7iMGnEUl9x33fbB/j3jR81u/O2LbqK+Bm1CDSNDKVtJ/YjwY7TUd5SkeLQLw==
+
+i2c-bus@^5.1.0:
+  version "5.1.0"
+  resolved "https://registry.yarnpkg.com/i2c-bus/-/i2c-bus-5.1.0.tgz#7d667d225c09017cf044f75fc593d5ea3e0f4ea6"
+  integrity sha512-u/q1fuZ5xrG77y3uo1rAANycboXsRNjneN+6jXRNMT2yRNpanVkbAP+IArwgsPRCHaY/zKxw7x5G8Y2fSPNseA==
+  dependencies:
+    bindings "^1.5.0"
+    nan "^2.14.0"
+
+nan@^2.14.0:
+  version "2.14.0"
+  resolved "https://registry.yarnpkg.com/nan/-/nan-2.14.0.tgz#7818f722027b2459a86f0295d434d1fc2336c52c"
+  integrity sha512-INOFj37C7k3AfaNTtX8RhsTw7qRy7eLET14cROi9+5HAVbbHuIWUHEauBv5qT4Av2tWasiTY1Jw6puUNqRJXQg==
+
+typescript@^3.6.4:
+  version "3.6.4"
+  resolved "https://registry.yarnpkg.com/typescript/-/typescript-3.6.4.tgz#b18752bb3792bc1a0281335f7f6ebf1bbfc5b91d"
+  integrity sha512-unoCll1+l+YK4i4F8f22TaNVPRHcD9PA3yCuZ8g5e0qGqlVlJ/8FSateOLLSagn+Yg5+ZwuPkL8LFUc0Jcvksg==