Defer initialize

js/script.js

@@ -26,7 +26,7 @@ document.addEventListener("DOMContentLoaded", () => {
   butConnect.addEventListener("click", () => {
     clickConnect().catch(async (e) => {
       console.error(e);
-      errorMsg(e.message);
+      errorMsg(e.message || e);
       if (espStub) {
         await espStub.disconnect();
       }
@@ -161,6 +161,12 @@ function enableStyleSheet(node, enabled) {
   node.disabled = !enabled;
 }
 
+function formatMacAddr(macAddr) {
+  return macAddr
+    .map((value) => value.toString(16).toUpperCase().padStart(2, "0"))
+    .join(":");
+}
+
 /**
  * @name clickConnect
  * Click handler for the connect/disconnect button.
@@ -180,13 +186,23 @@ async function clickConnect() {
     debug: (...args) => debugMsg(...args),
     error: (...args) => errorMsg(...args),
   });
-  espStub = await esploader.runStub();
-  toggleUIConnected(true);
-  toggleUIToolbar(true);
-  espStub.addEventListener("disconnect", () => {
-    toggleUIConnected(false);
-    espStub = false;
-  });
+  try {
+    await esploader.initialize();
+
+    logMsg("Connected to " + esploader.chipName);
+    logMsg("MAC Address: " + formatMacAddr(esploader.macAddr()));
+
+    espStub = await esploader.runStub();
+    toggleUIConnected(true);
+    toggleUIToolbar(true);
+    espStub.addEventListener("disconnect", () => {
+      toggleUIConnected(false);
+      espStub = false;
+    });
+  } catch (err) {
+    await esploader.disconnect();
+    throw err;
+  }
 }
 
 /**

src/esp_loader.ts

@@ -528,7 +528,7 @@ export class ESPLoader extends EventTarget {
   ) {
     let filesize = binaryData.byteLength;
     this.logger.log("\nWriting data with filesize:" + filesize);
-    let blocks = await this.flashBegin(filesize, offset);
+    await this.flashBegin(filesize, offset);
     let block = [];
     let seq = 0;
     let written = 0;

src/index.ts

@@ -1,6 +1,5 @@
 import { ESP_ROM_BAUD, Logger } from "./const";
 import { ESPLoader } from "./esp_loader";
-import { formatMacAddr } from "./util";
 
 export {
   CHIP_FAMILY_ESP32,
@@ -17,11 +16,5 @@ export const connect = async (logger: Logger) => {
 
   logger.log("Connected successfully.");
 
-  const esploader = new ESPLoader(port, logger);
-  await esploader.initialize();
-
-  logger.log("Connected to " + esploader.chipName);
-  logger.log("MAC Address: " + formatMacAddr(esploader.macAddr()));
-
-  return esploader;
+  return new ESPLoader(port, logger);
 };

src/util.ts

@@ -105,8 +105,3 @@ export const toHex = (value: number, size = 2) => {
 
 export const sleep = (ms: number) =>
   new Promise((resolve) => setTimeout(resolve, ms));
-
-export const formatMacAddr = (macAddr: number[]) =>
-  macAddr
-    .map((value) => value.toString(16).toUpperCase().padStart(2, "0"))
-    .join(":");