After connecting to Feather ESP32-S3 in Bluetooth, no file functions seem to work

[ericzundel]

CircuitPython Version

Adafruit CircuitPython 9.2.8 on 2025-05-28; Adafruit Feather ESP32S3 No PSRAM with ESP32S3
Board ID:adafruit_feather_esp32s3_nopsram

Note: I'm running in the latest Chrome on Windows 11.

When I connect via Bluetooth using the [learn.adafruit.com instructions](https://learn.adafruit.com/wirelessly-code-your-bluetooth-device-with-circuitpython/device-setup) 

I can see the serial console output, but none of the file functions seem to work. I get a spinning blinka icon and nothing in the JavaScript console.  

I've tried new, open, save as. Maybe also a clue: using Ctrl-C in the serial window also does nothing.

Workflow(s)

BLE

Browser(s)

Version 139.0.7258.155 (Official Build) (64-bit)

Console Log

Initializing File Transfer Client...
index.js:112 Connected!
index.js:112 Received: input: 
index.js:112  
index.js:112 None
index.js:112 
index.js:112 

index.js:112 Jiggle!

(the Jiggle! messages are from the script loaded on my CircuitPython device that output every few seconds)

Steps

1. Connect with the BLE workflow.
2. The connec dialog pops down on successful connection
3. Try hitting the Open button at the top left

Description

No response

Additional information

No response

[ericzundel]

I know there were just changes to the ble.js workflow. I reproduced this from main at commit 77e98ea today in my local development environment.

[ericzundel]

When I try the 'Open' button, it seems like listDir() in BLEFileTransferClient from @adafruit/ble-file-transfer-js is where the hang is occurring. I tracked it down by adding this patch:

diff --git a/js/common/ble-file-transfer.js b/js/common/ble-file-transfer.js
index fd7abf9..e69cabf 100644
--- a/js/common/ble-file-transfer.js
+++ b/js/common/ble-file-transfer.js
@@ -38,6 +38,13 @@ class FileTransferClient extends BLEFileTransferClient {

         return versionInfo;
     }
+
+    async listDir(arg) {
+        console.log("Calling listDir()");
+        result = await super.listDir(arg);
+        console.log("listDir() returned: ", result);
+        return result
+    }
 }

 export {FileTransferClient};
\ No newline at end of file

Console shows:

ble.js:216 Initializing File Transfer Client...  
workflow.js:118 Connected!
ble-file-transfer.js:43 Calling listDir()

[ericzundel]

    // Returns a list of tuples, one tuple for each file or directory in the given path
    async listDir(path) {
        await this.checkConnection();
        let encoded = new TextEncoder().encode(path);
        var header = new ArrayBuffer(4);
        var view = new DataView(header);
        view.setUint8(0, LISTDIR_COMMAND);
        // Offset 1 is reserved
        view.setUint16(2, encoded.byteLength, true);
        await this._write(header);
        await this._write(encoded);

        let p = new Promise((resolve, reject) => {
            this._resolve = resolve;
            this._reject = reject;
        });
        return p;
    }

I tried debugging into adafruit-ble-file-transfer.js some, but only found that the Event Listener callback registered for 'characteristicvaluechanged' doesn't seem to be getting called.

[ericzundel]

So, in summary, the serial characteristic seems to be working, but the file transfer characteristic isn't.

[makermelissa]

I wonder if this is related to the ESP32-S3 BLE implementation (though I doubt it). I'm not experiencing exactly the same thing with an nRF52840 board. It shows files, but has other issues.

[ericzundel]

I just ordered a nrf52840 board so we'll see if that works with Windows when it comes in.

[makermelissa]

Ok, I also have ESP32-S3 boards, so I'll try testing with those.

[ericzundel]

I just hooked up my nrf52840 board and the behavior was the same. The UI displays the blinka 'busy' animation and never returns. My microprocessor occasionally flashes a green light. My python code is just

import time

while True:
    print("Hello World")
    time.sleep(10)

boot_out.txt

Adafruit CircuitPython 9.2.9 on 2025-09-07; Adafruit Feather nRF52840 Express with nRF52840
Board ID:feather_nrf52840_express
UID:70A585A5F1E6326F

Here's what I see right after connecting in the serial window:

Requesting device. Cancel if empty and try existing

connecting to CIRCUITPY5239

connected

disconnected

The immediate 'disconnected' seems to indicate that something is going wrong.

[makermelissa]

I've was able to reproduce the issue, but only narrow it down where it's happening a little (it still disconnects, but control is returned to user).

[makermelissa]

Are you able to do any read operations (i.e. opening a file)? If write only, I will close this in favor of #377.

[ericzundel]

I'm not getting very far at all. For all I know, these are general windows connectivity issues. When I try connecting through the OS bluetooth settings first, I do see an error: Uncaught (in promise) NetworkError: GATT Server is disconnected. Cannot retrieve services. (Re)connect first with `device.gatt.connect`.

…

On Sun, Sep 28, 2025 at 5:01 PM Melissa LeBlanc-Williams < ***@***.***> wrote: *makermelissa* left a comment (circuitpython/web-editor#372) <#372 (comment)> Are you able to do any read operations (i.e. opening a file)? If write only, I will close this in favor of #377 <#377>. — Reply to this email directly, view it on GitHub <#372 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAA5HMAZB2HCIFMZSEMA6NT3VBEEBAVCNFSM6AAAAACF5ZATMOVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZTGNBUGI2TCMBRHE> . You are receiving this because you authored the thread.Message ID: ***@***.***>