diff --git a/index.html b/index.html
index 051b4e4..0a5caf5 100644
--- a/index.html
+++ b/index.html
@@ -224,6 +224,14 @@
 
 </div>
 
+<!-- setup web-serial-polyfill -->
+<script type="module">
+    import { serial } from "./js/web-serial-polyfill@1.0.15/dist/serial.js";
+    if(!navigator.serial && navigator.usb){
+        navigator.serial = serial;
+    }
+</script>
+
 <!-- setup esptool-js -->
 <script type="module">
     import { ESPLoader, Transport } from "./js/esptool-js@0.4.5/bundle.js";
diff --git a/js/web-serial-polyfill@1.0.15/dist/serial.js b/js/web-serial-polyfill@1.0.15/dist/serial.js
new file mode 100644
index 0000000..1741b7d
--- /dev/null
+++ b/js/web-serial-polyfill@1.0.15/dist/serial.js
@@ -0,0 +1,491 @@
+/*
+ * Copyright 2019 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in
+ * compliance with the License. You may obtain a copy of
+ * the License at
+ *
+ *    https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in
+ * writing, software distributed under the License is
+ * distributed on an "AS IS" BASIS, WITHOUT WARRANTIES
+ * OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing
+ * permissions and limitations under the License.
+ */
+'use strict';
+export var SerialPolyfillProtocol;
+(function (SerialPolyfillProtocol) {
+    SerialPolyfillProtocol[SerialPolyfillProtocol["UsbCdcAcm"] = 0] = "UsbCdcAcm";
+})(SerialPolyfillProtocol || (SerialPolyfillProtocol = {}));
+const kSetLineCoding = 0x20;
+const kSetControlLineState = 0x22;
+const kSendBreak = 0x23;
+const kDefaultBufferSize = 255;
+const kDefaultDataBits = 8;
+const kDefaultParity = 'none';
+const kDefaultStopBits = 1;
+const kAcceptableDataBits = [16, 8, 7, 6, 5];
+const kAcceptableStopBits = [1, 2];
+const kAcceptableParity = ['none', 'even', 'odd'];
+const kParityIndexMapping = ['none', 'odd', 'even'];
+const kStopBitsIndexMapping = [1, 1.5, 2];
+const kDefaultPolyfillOptions = {
+    protocol: SerialPolyfillProtocol.UsbCdcAcm,
+    usbControlInterfaceClass: 2,
+    usbTransferInterfaceClass: 10,
+};
+/**
+ * Utility function to get the interface implementing a desired class.
+ * @param {USBDevice} device The USB device.
+ * @param {number} classCode The desired interface class.
+ * @return {USBInterface} The first interface found that implements the desired
+ * class.
+ * @throws TypeError if no interface is found.
+ */
+function findInterface(device, classCode) {
+    const configuration = device.configurations[0];
+    for (const iface of configuration.interfaces) {
+        const alternate = iface.alternates[0];
+        if (alternate.interfaceClass === classCode) {
+            return iface;
+        }
+    }
+    throw new TypeError(`Unable to find interface with class ${classCode}.`);
+}
+/**
+ * Utility function to get an endpoint with a particular direction.
+ * @param {USBInterface} iface The interface to search.
+ * @param {USBDirection} direction The desired transfer direction.
+ * @return {USBEndpoint} The first endpoint with the desired transfer direction.
+ * @throws TypeError if no endpoint is found.
+ */
+function findEndpoint(iface, direction) {
+    const alternate = iface.alternates[0];
+    for (const endpoint of alternate.endpoints) {
+        if (endpoint.direction == direction) {
+            return endpoint;
+        }
+    }
+    throw new TypeError(`Interface ${iface.interfaceNumber} does not have an ` +
+        `${direction} endpoint.`);
+}
+/**
+ * Implementation of the underlying source API[1] which reads data from a USB
+ * endpoint. This can be used to construct a ReadableStream.
+ *
+ * [1]: https://streams.spec.whatwg.org/#underlying-source-api
+ */
+class UsbEndpointUnderlyingSource {
+    /**
+     * Constructs a new UnderlyingSource that will pull data from the specified
+     * endpoint on the given USB device.
+     *
+     * @param {USBDevice} device
+     * @param {USBEndpoint} endpoint
+     * @param {function} onError function to be called on error
+     */
+    constructor(device, endpoint, onError) {
+        this.type = 'bytes';
+        this.device_ = device;
+        this.endpoint_ = endpoint;
+        this.onError_ = onError;
+    }
+    /**
+     * Reads a chunk of data from the device.
+     *
+     * @param {ReadableByteStreamController} controller
+     */
+    pull(controller) {
+        (async () => {
+            var _a;
+            let chunkSize;
+            if (controller.desiredSize) {
+                const d = controller.desiredSize / this.endpoint_.packetSize;
+                chunkSize = Math.ceil(d) * this.endpoint_.packetSize;
+            }
+            else {
+                chunkSize = this.endpoint_.packetSize;
+            }
+            try {
+                const result = await this.device_.transferIn(this.endpoint_.endpointNumber, chunkSize);
+                if (result.status != 'ok') {
+                    controller.error(`USB error: ${result.status}`);
+                    this.onError_();
+                }
+                if ((_a = result.data) === null || _a === void 0 ? void 0 : _a.buffer) {
+                    const chunk = new Uint8Array(result.data.buffer, result.data.byteOffset, result.data.byteLength);
+                    controller.enqueue(chunk);
+                }
+            }
+            catch (error) {
+                controller.error(error.toString());
+                this.onError_();
+            }
+        })();
+    }
+}
+/**
+ * Implementation of the underlying sink API[2] which writes data to a USB
+ * endpoint. This can be used to construct a WritableStream.
+ *
+ * [2]: https://streams.spec.whatwg.org/#underlying-sink-api
+ */
+class UsbEndpointUnderlyingSink {
+    /**
+     * Constructs a new UnderlyingSink that will write data to the specified
+     * endpoint on the given USB device.
+     *
+     * @param {USBDevice} device
+     * @param {USBEndpoint} endpoint
+     * @param {function} onError function to be called on error
+     */
+    constructor(device, endpoint, onError) {
+        this.device_ = device;
+        this.endpoint_ = endpoint;
+        this.onError_ = onError;
+    }
+    /**
+     * Writes a chunk to the device.
+     *
+     * @param {Uint8Array} chunk
+     * @param {WritableStreamDefaultController} controller
+     */
+    async write(chunk, controller) {
+        try {
+            const result = await this.device_.transferOut(this.endpoint_.endpointNumber, chunk);
+            if (result.status != 'ok') {
+                controller.error(result.status);
+                this.onError_();
+            }
+        }
+        catch (error) {
+            controller.error(error.toString());
+            this.onError_();
+        }
+    }
+}
+/** a class used to control serial devices over WebUSB */
+export class SerialPort {
+    /**
+     * constructor taking a WebUSB device that creates a SerialPort instance.
+     * @param {USBDevice} device A device acquired from the WebUSB API
+     * @param {SerialPolyfillOptions} polyfillOptions Optional options to
+     * configure the polyfill.
+     */
+    constructor(device, polyfillOptions) {
+        this.polyfillOptions_ = Object.assign(Object.assign({}, kDefaultPolyfillOptions), polyfillOptions);
+        this.outputSignals_ = {
+            dataTerminalReady: false,
+            requestToSend: false,
+            break: false,
+        };
+        this.device_ = device;
+        this.controlInterface_ = findInterface(this.device_, this.polyfillOptions_.usbControlInterfaceClass);
+        this.transferInterface_ = findInterface(this.device_, this.polyfillOptions_.usbTransferInterfaceClass);
+        this.inEndpoint_ = findEndpoint(this.transferInterface_, 'in');
+        this.outEndpoint_ = findEndpoint(this.transferInterface_, 'out');
+    }
+    /**
+     * Getter for the readable attribute. Constructs a new ReadableStream as
+     * necessary.
+     * @return {ReadableStream} the current readable stream
+     */
+    get readable() {
+        var _a;
+        if (!this.readable_ && this.device_.opened) {
+            this.readable_ = new ReadableStream(new UsbEndpointUnderlyingSource(this.device_, this.inEndpoint_, () => {
+                this.readable_ = null;
+            }), {
+                highWaterMark: (_a = this.serialOptions_.bufferSize) !== null && _a !== void 0 ? _a : kDefaultBufferSize,
+            });
+        }
+        return this.readable_;
+    }
+    /**
+     * Getter for the writable attribute. Constructs a new WritableStream as
+     * necessary.
+     * @return {WritableStream} the current writable stream
+     */
+    get writable() {
+        var _a;
+        if (!this.writable_ && this.device_.opened) {
+            this.writable_ = new WritableStream(new UsbEndpointUnderlyingSink(this.device_, this.outEndpoint_, () => {
+                this.writable_ = null;
+            }), new ByteLengthQueuingStrategy({
+                highWaterMark: (_a = this.serialOptions_.bufferSize) !== null && _a !== void 0 ? _a : kDefaultBufferSize,
+            }));
+        }
+        return this.writable_;
+    }
+    /**
+     * a function that opens the device and claims all interfaces needed to
+     * control and communicate to and from the serial device
+     * @param {SerialOptions} options Object containing serial options
+     * @return {Promise<void>} A promise that will resolve when device is ready
+     * for communication
+     */
+    async open(options) {
+        this.serialOptions_ = options;
+        this.validateOptions();
+        try {
+            await this.device_.open();
+            if (this.device_.configuration === null) {
+                await this.device_.selectConfiguration(1);
+            }
+            await this.device_.claimInterface(this.controlInterface_.interfaceNumber);
+            if (this.controlInterface_ !== this.transferInterface_) {
+                await this.device_.claimInterface(this.transferInterface_.interfaceNumber);
+            }
+            await this.setLineCoding();
+            await this.setSignals({ dataTerminalReady: true });
+        }
+        catch (error) {
+            if (this.device_.opened) {
+                await this.device_.close();
+            }
+            throw new Error('Error setting up device: ' + error.toString());
+        }
+    }
+    /**
+     * Closes the port.
+     *
+     * @return {Promise<void>} A promise that will resolve when the port is
+     * closed.
+     */
+    async close() {
+        const promises = [];
+        if (this.readable_) {
+            promises.push(this.readable_.cancel());
+        }
+        if (this.writable_) {
+            promises.push(this.writable_.abort());
+        }
+        await Promise.all(promises);
+        this.readable_ = null;
+        this.writable_ = null;
+        if (this.device_.opened) {
+            await this.setSignals({ dataTerminalReady: false, requestToSend: false });
+            await this.device_.close();
+        }
+    }
+    /**
+     * Forgets the port.
+     *
+     * @return {Promise<void>} A promise that will resolve when the port is
+     * forgotten.
+     */
+    async forget() {
+        return this.device_.forget();
+    }
+    /**
+     * A function that returns properties of the device.
+     * @return {SerialPortInfo} Device properties.
+     */
+    getInfo() {
+        return {
+            usbVendorId: this.device_.vendorId,
+            usbProductId: this.device_.productId,
+        };
+    }
+    /**
+     * A function used to change the serial settings of the device
+     * @param {object} options the object which carries serial settings data
+     * @return {Promise<void>} A promise that will resolve when the options are
+     * set
+     */
+    reconfigure(options) {
+        this.serialOptions_ = Object.assign(Object.assign({}, this.serialOptions_), options);
+        this.validateOptions();
+        return this.setLineCoding();
+    }
+    /**
+     * Sets control signal state for the port.
+     * @param {SerialOutputSignals} signals The signals to enable or disable.
+     * @return {Promise<void>} a promise that is resolved when the signal state
+     * has been changed.
+     */
+    async setSignals(signals) {
+        this.outputSignals_ = Object.assign(Object.assign({}, this.outputSignals_), signals);
+        if (signals.dataTerminalReady !== undefined ||
+            signals.requestToSend !== undefined) {
+            // The Set_Control_Line_State command expects a bitmap containing the
+            // values of all output signals that should be enabled or disabled.
+            //
+            // Ref: USB CDC specification version 1.1 §6.2.14.
+            const value = (this.outputSignals_.dataTerminalReady ? 1 << 0 : 0) |
+                (this.outputSignals_.requestToSend ? 1 << 1 : 0);
+            await this.device_.controlTransferOut({
+                'requestType': 'class',
+                'recipient': 'interface',
+                'request': kSetControlLineState,
+                'value': value,
+                'index': this.controlInterface_.interfaceNumber,
+            });
+        }
+        if (signals.break !== undefined) {
+            // The SendBreak command expects to be given a duration for how long the
+            // break signal should be asserted. Passing 0xFFFF enables the signal
+            // until 0x0000 is send.
+            //
+            // Ref: USB CDC specification version 1.1 §6.2.15.
+            const value = this.outputSignals_.break ? 0xFFFF : 0x0000;
+            await this.device_.controlTransferOut({
+                'requestType': 'class',
+                'recipient': 'interface',
+                'request': kSendBreak,
+                'value': value,
+                'index': this.controlInterface_.interfaceNumber,
+            });
+        }
+    }
+    /**
+     * Checks the serial options for validity and throws an error if it is
+     * not valid
+     */
+    validateOptions() {
+        if (!this.isValidBaudRate(this.serialOptions_.baudRate)) {
+            throw new RangeError('invalid Baud Rate ' + this.serialOptions_.baudRate);
+        }
+        if (!this.isValidDataBits(this.serialOptions_.dataBits)) {
+            throw new RangeError('invalid dataBits ' + this.serialOptions_.dataBits);
+        }
+        if (!this.isValidStopBits(this.serialOptions_.stopBits)) {
+            throw new RangeError('invalid stopBits ' + this.serialOptions_.stopBits);
+        }
+        if (!this.isValidParity(this.serialOptions_.parity)) {
+            throw new RangeError('invalid parity ' + this.serialOptions_.parity);
+        }
+    }
+    /**
+     * Checks the baud rate for validity
+     * @param {number} baudRate the baud rate to check
+     * @return {boolean} A boolean that reflects whether the baud rate is valid
+     */
+    isValidBaudRate(baudRate) {
+        return baudRate % 1 === 0;
+    }
+    /**
+     * Checks the data bits for validity
+     * @param {number} dataBits the data bits to check
+     * @return {boolean} A boolean that reflects whether the data bits setting is
+     * valid
+     */
+    isValidDataBits(dataBits) {
+        if (typeof dataBits === 'undefined') {
+            return true;
+        }
+        return kAcceptableDataBits.includes(dataBits);
+    }
+    /**
+     * Checks the stop bits for validity
+     * @param {number} stopBits the stop bits to check
+     * @return {boolean} A boolean that reflects whether the stop bits setting is
+     * valid
+     */
+    isValidStopBits(stopBits) {
+        if (typeof stopBits === 'undefined') {
+            return true;
+        }
+        return kAcceptableStopBits.includes(stopBits);
+    }
+    /**
+     * Checks the parity for validity
+     * @param {string} parity the parity to check
+     * @return {boolean} A boolean that reflects whether the parity is valid
+     */
+    isValidParity(parity) {
+        if (typeof parity === 'undefined') {
+            return true;
+        }
+        return kAcceptableParity.includes(parity);
+    }
+    /**
+     * sends the options alog the control interface to set them on the device
+     * @return {Promise} a promise that will resolve when the options are set
+     */
+    async setLineCoding() {
+        var _a, _b, _c;
+        // Ref: USB CDC specification version 1.1 §6.2.12.
+        const buffer = new ArrayBuffer(7);
+        const view = new DataView(buffer);
+        view.setUint32(0, this.serialOptions_.baudRate, true);
+        view.setUint8(4, kStopBitsIndexMapping.indexOf((_a = this.serialOptions_.stopBits) !== null && _a !== void 0 ? _a : kDefaultStopBits));
+        view.setUint8(5, kParityIndexMapping.indexOf((_b = this.serialOptions_.parity) !== null && _b !== void 0 ? _b : kDefaultParity));
+        view.setUint8(6, (_c = this.serialOptions_.dataBits) !== null && _c !== void 0 ? _c : kDefaultDataBits);
+        const result = await this.device_.controlTransferOut({
+            'requestType': 'class',
+            'recipient': 'interface',
+            'request': kSetLineCoding,
+            'value': 0x00,
+            'index': this.controlInterface_.interfaceNumber,
+        }, buffer);
+        if (result.status != 'ok') {
+            throw new DOMException('NetworkError', 'Failed to set line coding.');
+        }
+    }
+}
+/** implementation of the global navigator.serial object */
+class Serial {
+    /**
+     * Requests permission to access a new port.
+     *
+     * @param {SerialPortRequestOptions} options
+     * @param {SerialPolyfillOptions} polyfillOptions
+     * @return {Promise<SerialPort>}
+     */
+    async requestPort(options, polyfillOptions) {
+        polyfillOptions = Object.assign(Object.assign({}, kDefaultPolyfillOptions), polyfillOptions);
+        const usbFilters = [];
+        if (options && options.filters) {
+            for (const filter of options.filters) {
+                const usbFilter = {
+                    classCode: polyfillOptions.usbControlInterfaceClass,
+                };
+                if (filter.usbVendorId !== undefined) {
+                    usbFilter.vendorId = filter.usbVendorId;
+                }
+                if (filter.usbProductId !== undefined) {
+                    usbFilter.productId = filter.usbProductId;
+                }
+                usbFilters.push(usbFilter);
+            }
+        }
+        if (usbFilters.length === 0) {
+            usbFilters.push({
+                classCode: polyfillOptions.usbControlInterfaceClass,
+            });
+        }
+        const device = await navigator.usb.requestDevice({ 'filters': usbFilters });
+        const port = new SerialPort(device, polyfillOptions);
+        return port;
+    }
+    /**
+     * Get the set of currently available ports.
+     *
+     * @param {SerialPolyfillOptions} polyfillOptions Polyfill configuration that
+     * should be applied to these ports.
+     * @return {Promise<SerialPort[]>} a promise that is resolved with a list of
+     * ports.
+     */
+    async getPorts(polyfillOptions) {
+        polyfillOptions = Object.assign(Object.assign({}, kDefaultPolyfillOptions), polyfillOptions);
+        const devices = await navigator.usb.getDevices();
+        const ports = [];
+        devices.forEach((device) => {
+            try {
+                const port = new SerialPort(device, polyfillOptions);
+                ports.push(port);
+            }
+            catch (e) {
+                // Skip unrecognized port.
+            }
+        });
+        return ports;
+    }
+}
+/* an object to be used for starting the serial workflow */
+export const serial = new Serial();
+//# sourceMappingURL=serial.js.map
\ No newline at end of file