clear command buffers before flashing

microsoft · Aug 23, 2024 · 1fc5c3e · 1fc5c3e
1 parent b075e3b
commit 1fc5c3e
Showing 1 changed file with 54 additions and 53 deletions.
diff --git a/editor/flash.ts b/editor/flash.ts
@@ -128,7 +128,7 @@ class DAPWrapper implements pxt.packetio.PacketIOWrapper {
     }
 
     private async readSerial(): Promise<number> {
-        let buf = await this.dapCmdNums(0x83)
+        let buf = await this.dapCmdNums(0x83); // 131
         const len = buf[1]
         // concat received data with previous data
         if (len) {
@@ -167,58 +167,54 @@ class DAPWrapper implements pxt.packetio.PacketIOWrapper {
         return len
     }
 
-    private startReadSerial(connectionId: number) {
+    private async startReadSerial(connectionId: number) {
         const startTime = Date.now();
         log(`start read serial ${connectionId}`)
-        const readSerialLoop = async () => {
-            try {
-                let numSer = 0
-                let numEv = 0
-                while (connectionId === this.connectionId) {
-                    numSer = await this.readSerial()
-                    // we need to read jacdac in a tight loop
-                    // so we don't miss any event
-                    if (this.xchgAddr)
-                        numEv = await this.jacdacProcess()
-                    else
-                        numEv = 0
-
-                    // no data on either side, wait as little as possible
-                    // the browser will eventually throttle this call
-                    // https://developer.mozilla.org/en-US/docs/Web/API/setTimeout#reasons_for_delays_longer_than_specified
-                    if (!numSer && !numEv)
-                        await pxt.U.delay(0)
-                }
+        try {
+            let numSer = 0
+            let numEv = 0
+            while (connectionId === this.connectionId) {
+                numSer = await this.readSerial()
+                // we need to read jacdac in a tight loop
+                // so we don't miss any event
+                if (this.xchgAddr)
+                    numEv = await this.jacdacProcess()
+                else
+                    numEv = 0
+
+                // no data on either side, wait as little as possible
+                // the browser will eventually throttle this call
+                // https://developer.mozilla.org/en-US/docs/Web/API/setTimeout#reasons_for_delays_longer_than_specified
+                if (!numSer && !numEv)
+                    await pxt.U.delay(0)
+            }
+            log(`stopped serial reader ${connectionId}`)
+        } catch (err) {
+            log(`serial error ${connectionId}: ${err.message}`);
+            console.error(err)
+            if (connectionId != this.connectionId) {
                 log(`stopped serial reader ${connectionId}`)
-            } catch (err) {
-                log(`serial error ${connectionId}: ${err.message}`);
-                console.error(err)
-                if (connectionId != this.connectionId) {
-                    log(`stopped serial reader ${connectionId}`)
-                } else {
-                    pxt.tickEvent("hid.flash.serial.error");
-                    const timeRunning = Date.now() - startTime
-                    await this.disconnectAsync(); // force disconnect
-                    // if we've been running for a while, try reconnecting
-                    if (timeRunning > 1000) {
-                        log(`auto-reconnect`)
-                        try {
-                            await this.reconnectAsync();
-                        } catch (e) {
-                            if (e.type === "devicenotfound")
-                                return
-                            throw e
-                        }
+            } else {
+                pxt.tickEvent("hid.flash.serial.error");
+                const timeRunning = Date.now() - startTime
+                await this.disconnectAsync(); // force disconnect
+                // if we've been running for a while, try reconnecting
+                if (timeRunning > 1000) {
+                    log(`auto-reconnect`)
+                    try {
+                        await this.reconnectAsync();
+                    } catch (e) {
+                        if (e.type === "devicenotfound")
+                            return
+                        throw e
                     }
                 }
             }
-            finally {
-                this.pendingSerial = undefined
-                this.lastPendingSerial = undefined
-            }
         }
-
-        readSerialLoop();
+        finally {
+            this.pendingSerial = undefined
+            this.lastPendingSerial = undefined
+        }
     }
 
     private stopReadersAsync() {
@@ -312,13 +308,7 @@ class DAPWrapper implements pxt.packetio.PacketIOWrapper {
 
         await this.io.reconnectAsync()
 
-        // before calling into dapjs, push through a few commands to make sure the responses
-        // to commands from previous sessions (if any) are flushed. Count of 5 is arbitrary.
-        for (let i = 0; i < 5; i++) {
-            try {
-                await this.getDaplinkVersionAsync();
-            } catch (e) {}
-        }
+        await this.clearCommandsAsync()
 
         // halt before reading from dap
         // to avoid interference from data logger
@@ -355,6 +345,16 @@ class DAPWrapper implements pxt.packetio.PacketIOWrapper {
         this.startReadSerial(connectionId)
     }
 
+    private async clearCommandsAsync() {
+        // before calling into dapjs, push through a few commands to make sure the responses
+        // to commands from previous sessions (if any) are flushed. Count of 5 is arbitrary.
+        for (let i = 0; i < 5; i++) {
+            try {
+                await this.getDaplinkVersionAsync();
+            } catch (e) {}
+        }
+    }
+
     private async getDaplinkVersionAsync() {
         return await this.dapCmdNums(0x00, 0x04);
     }
@@ -402,6 +402,7 @@ class DAPWrapper implements pxt.packetio.PacketIOWrapper {
             await this.io.reconnectAsync();
         }
 
+        await this.clearCommandsAsync()
         await this.stopReadersAsync();
         await this.cortexM.init();
         await this.cortexM.reset(true);