attempted crc work and blob usage

package.json

@@ -1,15 +1,12 @@
 {
   "name": "@johntalton/excamera-i2cdriver",
-  "version": "2.0.0",
+  "version": "2.0.1",
   "type": "module",
   "exports": {
     ".": "./src/i2c-driver.js",
-    "./capture": "./src/capture-generator/index.js",
-    "./package.json": "./package.json"
+    "./capture": "./src/capture-generator/index.js"
   },
-  "files": [ "src/**/*.js"],
-  "scripts": {
-  },
-  "dependencies": {
-  }
+  "files": [
+    "src/**/*.js"
+  ]
 }

src/crc-16-ccitt.js

@@ -1,3 +1,6 @@
+
+export const INITIAL_CRC = 0xffff
+
 const LOOKUP_TABLE = [
 	0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7,
 	0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef,
@@ -33,11 +36,19 @@ const LOOKUP_TABLE = [
 	0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0x0ed1, 0x1ef0
 ]
 
-export function crcUpdate(startCRC = 0xffff, bufferSource) {
-	// todo ... validate buffersource
+export function crcUpdate(startCRC = INITIAL_CRC, buffer, count) {
+
+	const u8 = ArrayBuffer.isView(buffer) ?
+		new Uint8Array(buffer.buffer, buffer.byteOffset, buffer.byteLength) :
+		new Uint8Array(buffer)
+
+		// console.log('up', [...u8])
+
+	if(u8.byteLength !== count) { throw new Error('count miss-match') }
 
-	return [ ...bufferSource ].reduce((crc, value) => {
-		const idx = ((crc >> 8) ^ value) & 0xff
+	return [ ...u8 ].reduce((crc, value) => {
+		const b = value & 0xff
+		const idx = ((crc >> 8) ^ b) & 0xff
 		return (LOOKUP_TABLE[idx] ^ (crc << 8)) & 0xffff
 	}, startCRC)
 }

src/i2c-driver.js

@@ -1,3 +1,4 @@
+import { INITIAL_CRC, crcUpdate } from './crc-16-ccitt.js'
 import { ResponseBufferParser } from './parse-buffers.js'
 
 export const EXCAMERA_LABS_VENDOR_ID = 0x0403
@@ -43,8 +44,8 @@ const COMMAND_REBOOT = 0x5f // '_'
 
 //
 const COMMAND_EFF = 0x66 // 'f'
-const COMMAND_UHOO = 0x76 // 'v'
-const COMMAND_DUBU = 0x77 // 'w'
+const COMMAND_UHOO = 0x76 // 'v' start weight
+const COMMAND_DUBU = 0x77 // 'w' weight
 
 
 
@@ -56,6 +57,7 @@ const COMMAND_REPLY_LENGTH_INTERNAL_STATE = 80
 
 export class ExcameraLabsI2CDriverI2C {
 	#port
+	#crc = INITIAL_CRC
 
 	static from(options) { return new ExcameraLabsI2CDriverI2C(options) }
 
@@ -64,18 +66,58 @@ export class ExcameraLabsI2CDriverI2C {
 	 */
 	constructor({ port }) { this.#port = port }
 
-	async start(dev, readMode) { return ExcameraLabsI2CDriver.start(this.#port, dev, readMode) }
+	get crc() { return this.#crc }
+	set crc(crc) { this.#crc = crc }
+
+	async start(dev, readMode) {
+		return ExcameraLabsI2CDriver.start(this.#port, dev, readMode)
+			// .then(buffer => {
+			// 	this.#crc = crcUpdate(this.#crc, Uint8Array.from([ dev ]), 1)
+			// 	return buffer
+			// })
+	}
+
 	async stop() { return ExcameraLabsI2CDriver.stop(this.#port) }
-	async readACKAll(count) { return ExcameraLabsI2CDriver.readACKAll(this.#port, count) }
-	async readNACKFinal(count) { return ExcameraLabsI2CDriver.readNACKFinal(this.#port, count) }
-	async write(count, bufferSource) { return ExcameraLabsI2CDriver.write(this.#port, count, bufferSource) }
 
-	async readRegister(dev, addr, count) { return ExcameraLabsI2CDriver.readRegister(this.#port, dev, addr, count) }
+	async readACKAll(count) {
+		return ExcameraLabsI2CDriver.readACKAll(this.#port, count)
+			// .then(buffer => {
+			// 	this.#crc = crcUpdate(this.#crc, buffer, count)
+			// 	return buffer
+			// })
+	}
+
+	async readNACKFinal(count) {
+		return ExcameraLabsI2CDriver.readNACKFinal(this.#port, count)
+			// .then(buffer => {
+			// 	this.#crc = crcUpdate(this.#crc, buffer, count)
+			// 	return buffer
+			// })
+	}
+
+	async write(count, bufferSource) {
+		return ExcameraLabsI2CDriver.write(this.#port, count, bufferSource)
+			// .then(state => {
+			// 	this.#crc = crcUpdate(this.#crc, bufferSource, count)
+			// 	return state
+			// })
+	}
+
+	async readRegister(dev, addr, count) {
+		return ExcameraLabsI2CDriver.readRegister(this.#port, dev, addr, count)
+			// .then(value => {
+			// 	const buffer = Uint8Array.from([ value ])
+			// 	this.#crc = crcUpdate(this.#crc, buffer, count)
+			// 	return value
+			// })
+	}
+
 	async resetBus() { return ExcameraLabsI2CDriver.resetBus(this.#port) }
 	async transmitStatusInfo() { return ExcameraLabsI2CDriver.transmitStatusInfo(this.#port) }
 }
 
 
+
 export class ExcameraLabsI2CDriver {
 	// static controlFrom({ port }) {
 	// 	return {
@@ -108,12 +150,13 @@ export class ExcameraLabsI2CDriver {
 	// 	}
 	// }
 
+	static READ_TIMEOUT_MS = 1000 * 2
 
 	static async #streamChunkRead(defaultReader, recvLength) {
 		const timer = setTimeout(() => {
-			console.log('timeout')
+			console.log('read timeout')
 			defaultReader.cancel()
-		}, 2000)
+		}, ExcameraLabsI2CDriver.READ_TIMEOUT_MS)
 
 		const scratch = {
 			accumulator: [],
@@ -127,19 +170,18 @@ export class ExcameraLabsI2CDriver {
 			scratch.accumulator.push(value)
 			scratch.length += value.length
 
-			if(scratch.length >= recvLength) {
+			if(scratch.length === recvLength) { break }
+
+			if(scratch.length > recvLength) {
 				// console.log('OVERSIZE')
 				break
 			}
 		}
 
 		clearTimeout(timer)
 
-		//console.log({ acc })
-		// return Uint8Array.from(acc.reduce((flat, a) => {
-		// 	return [ ...flat, ...a ]
-		// }, []))
-		return (new Blob(scratch.accumulator)).arrayBuffer()
+		const blob = new Blob(scratch.accumulator)
+		return blob.arrayBuffer()
 	}
 
 	static async #streamChunkRead_Alt(defaultReader, recvLength) {
@@ -172,65 +214,43 @@ export class ExcameraLabsI2CDriver {
 	static async sendRecvTextCommand(port, textCommand, sendBuffer, recvLength) {
 		const encoder = new TextEncoder()
 		const encoded = encoder.encode(textCommand, { stream: false })
-		if(encoded.byteLength !== 1) { throw new Error('unknown text command')}
+		// if(encoded.byteLength !== 1) { throw new Error('unknown text command')}
 
 		const command = encoded[0]
 		return this.sendRecvCommand(port, command, sendBuffer, recvLength)
 	}
 
 	/**
 	 * @param {SerialPort} port
-	 * @param {ArrayBufferLike|ArrayBufferView} sendBuffer
+	 * @param {ArrayBufferLike|ArrayBufferView|undefined} sendBuffer
 	*/
 	static async sendRecvCommand(port, command, sendBuffer, recvLength) {
-		// console.log('reader state', port.readable.locked, command, sendBuffer, recvLength)
-		if(port.readable.locked) {
-			console.warn('locked reader ...')
-
-			return new ArrayBuffer(0)
-			//throw new Error('locked reader')
-		}
+		if(port.readable === null) { throw new Error('null readable') }
+		if(port.readable.locked) { throw new Error('locked reader') }
 
 		const defaultWriter = port.writable.getWriter()
 		const defaultReader = port.readable.getReader()
 
 		try {
-			//
-			// console.log('write encoded command', command)
 			await defaultWriter.ready
 
-			if(sendBuffer) {
-				const sb8 = ArrayBuffer.isView(sendBuffer) ?
-					new Uint8Array(sendBuffer.buffer, sendBuffer.byteOffset, sendBuffer.byteLength) :
-					new Uint8Array(sendBuffer)
-
-				// console.log('sending buffer', sb8)
-
-				await defaultWriter.write(Uint8Array.from([ command, ...sb8 ]))
-			}
-			else {
-				await defaultWriter.write(Uint8Array.from([ command ]))
-			}
-
-			//
-			// console.log('close writer')
-			// await defaultWriter.ready
-			// await defaultWriter.close()
+			const commandBuffer = Uint8Array.from([ command ])
+			const parts = sendBuffer !== undefined ? [ commandBuffer, sendBuffer ] : [ commandBuffer ]
+			const blob = new Blob(parts)
+			const buffer = await blob.arrayBuffer()
+			await defaultWriter.write(buffer)
 
-			// console.log({ recvLength })
 			if(recvLength === undefined || recvLength <= 0) {
-				// console.log('expect zero')
-				return Uint8Array.from([])
+				return new ArrayBuffer(0)
 			}
 
+			// return await here as otherwise the finally release the lock before the read
 			return await ExcameraLabsI2CDriver.#streamChunkRead(defaultReader, recvLength)
 		}
 		catch(e) {
-			console.warn(e)
-			return Uint8Array.from([])
+			throw e
 		}
 		finally {
-			// console.log('finally')
 			await defaultWriter.ready
 
 			await defaultReader.releaseLock()