Timeout-Error When Reading Flash

ICEBEAR · January 18, 2026, 12:22am

Hello everyone,

I’m currently trying to read out the flash of a Toniebox using an ESP32-S3, doing the process via browser on Win11.

The flash read itself completes without issues and reaches 100% successfully.
However, during the verify/check step, the process fails with a timeout at line 19.
(Timeout after 16777 ms waiting for response to command 19)

I have another Toniebox and that flash worked fine

henryk · January 18, 2026, 5:51am

@g3gg0 any idea?

g3gg0 · January 18, 2026, 9:37am

Did you try the flasher separately?

If it persists, enter advanced mode and check console.

If that works, check ESP32 Firmware Editor if that works aswell

ICEBEAR · January 18, 2026, 11:48am

@g3gg0: I can connect.. Then i can press reset (Download).

And when i press sync&detect he sais “Connected (Sync Failed) PROBLEM”

ICEBEAR · January 18, 2026, 11:56am

[12:55:08] Starting sync process…

[12:55:09] Sync successful! Detected chip: esp32s3

[12:55:09] Loaded 7 register presets for esp32s3

[12:55:09] MAC Address: f4:12:fa:4c:21:b4

[12:55:30] Advanced mode ENABLED

Okay so far it worked for now… but the Firware editor will not

ICEBEAR · January 18, 2026, 11:58am

oh, when i disconnect the first tool it worked. and now?

g3gg0 · January 18, 2026, 12:03pm

can you show screenshots of what does not/work?

g3gg0 · January 18, 2026, 12:10pm

ICEBEAR · January 18, 2026, 1:12pm

The most time he is aborting while it is reading.

ICEBEAR · January 18, 2026, 1:13pm

Only 1 time i got to this point and there he aborted

ICEBEAR · January 18, 2026, 1:36pm

g3gg0 · January 18, 2026, 1:42pm

are you sure the battery and connection is good?

ICEBEAR · January 18, 2026, 2:27pm

Looks like. The battery is loading now. And I will try it later again. I don’t know why the connection is so bad. With my other box it works fine.

ICEBEAR · January 18, 2026, 6:59pm

I don’t know if it is normal or a problem. The contact auf 103 looks very rough. Maybe this is the problem?

@g3gg0

g3gg0 · January 18, 2026, 8:43pm

how do you contact the pads?

ICEBEAR · January 19, 2026, 8:23am

With this clamp.

Rapptor · January 24, 2026, 5:17pm

Hello, got similar Problem, it’s starts reading but then it stops
How did you fix it?
I also use clamp. Battery is full.

Ready. Click ‘Connect Device’ to start.

[18:13:48] ESP32 Flasher Test Suite initialized

[18:13:48] Supported chips: ESP32, ESP32-S2, ESP32-S3, ESP32-C3, ESP32-C6

[18:13:49] Requesting Web Serial port…

[18:13:51] Port opened successfully

[18:13:51] Note: Web Serial cannot change baud rate without reopening; to avoid unintended resets we keep one baud from start to end. The ROM prints reset messages at 115200. With USB-UART RX/TX wiring you must choose: slow baud (115200) to see reset messages, or high baud (e.g., 921600) to get speed but miss those messages.

[18:13:51] Please click “Hard Reset” to continue…

[18:13:52] Initiating reset to download mode…

[18:13:52] Reset to download mode successful

[18:13:52] Please click “Sync & Detect” to continue…

[18:13:54] Starting sync process…

[18:13:54] Sync successful! Detected chip: esp32s3

[18:13:54] Loaded 7 register presets for esp32s3

[18:13:54] MAC Address: xxxxxxxxxxxxxxxxxxx

[18:13:57] Loading stub loader…

[18:13:58] Stub loaded successfully!

[18:14:02] Reading 8388608 bytes from flash at 0x00000000 with MD5 verification…

[18:14:03] Read 40960 / 8388608 bytes (0%)

[18:14:03] Read 81920 / 8388608 bytes (1%)

[18:14:04] Read 122880 / 8388608 bytes (1%)

[18:14:04] Read 163840 / 8388608 bytes (2%)

[18:14:05] Read 204800 / 8388608 bytes (2%)

[18:14:07] [ERROR] [ReadFlashPlain] TIMEOUT CHECK: timeSinceLastData=1333ms, triggering timeout

[18:14:07] [ERROR] ReadFlashSafe failed: Timeout in command 210

[18:14:07] Flash read error: Timeout in command 210

ICEBEAR · January 24, 2026, 6:15pm

Haven’t fixed it

Kevin_B · January 29, 2026, 2:10pm

Same problem here.

[INFO] 2026-01-29 14:53:49 [ESP32] WebSerial supported? {“supported”:true}

[INFO] 2026-01-29 14:53:49 [ESP32] HTTPS active

[INFO] 2026-01-29 14:55:50 [ESP32] readFlash: start {“step”:1,“useRevvoxFlasher”:true,“baudRate”:921600,“romBaudRate”:115200,“resetBox”:false}

[INFO] 2026-01-29 14:55:50 [ESP32][Revvox] prepare: start {“step”:1,“useRevvoxFlasher”:true,“baudRate”:921600,“romBaudRate”:115200,“resetBox”:false}

[INFO] 2026-01-29 14:55:50 [ESP32][Revvox] Creating RevvoxFlasher instance {“step”:1,“useRevvoxFlasher”:true,“baudRate”:921600,“romBaudRate”:115200,“resetBox”:false}

[INFO] 2026-01-29 14:55:50 [ESP32][Revvox] prepare: openPort…

[INFO] 2026-01-29 14:55:54 [ESP32][Revvox] prepare: sync…

[DEBUG] 2026-01-29 14:55:54 [RevvoxFlasher] Attempting to synchronize (10 attempts)…

[DEBUG] 2026-01-29 14:55:54 [RevvoxFlasher] Sync attempt 1…

[DEBUG] 2026-01-29 14:55:54 [RevvoxFlasher] [CMD] SYNC (0x08) params: {“dir”:0,“command”:8,“size”:36,“value”:239,“data”:“36 bytes”,“raw”:“44 bytes”}

[DEBUG] 2026-01-29 14:55:55 [RevvoxFlasher] Sync attempt 1 failed: Timeout after 250 ms waiting for response to command 8

[DEBUG] 2026-01-29 14:55:55 [RevvoxFlasher] Sync attempt 2…

[DEBUG] 2026-01-29 14:55:55 [RevvoxFlasher] [CMD] SYNC (0x08) params: {“dir”:0,“command”:8,“size”:36,“value”:239,“data”:“36 bytes”,“raw”:“44 bytes”}

[DEBUG] 2026-01-29 14:55:55 [RevvoxFlasher] Synchronized successfully on attempt 2.

[DEBUG] 2026-01-29 14:55:55 [RevvoxFlasher] Reading chip magic value…

[DEBUG] 2026-01-29 14:55:55 [RevvoxFlasher] [CMD] READ_REG (0x0a) params: {“dir”:0,“command”:10,“size”:4,“value”:0,“data”:“4 bytes”,“raw”:“12 bytes”}

[DEBUG] 2026-01-29 14:55:55 [RevvoxFlasher] Detected Chip: esp32s3 (Magic: 0x9)

[INFO] 2026-01-29 14:55:55 [ESP32][Revvox] prepare: port open + sync OK

[INFO] 2026-01-29 14:55:55 [ESP32][Revvox] prepare: reliability check start

[DEBUG] 2026-01-29 14:55:55 [RevvoxFlasher] [CMD] READ_REG (0x0a) params: {“dir”:0,“command”:10,“size”:4,“value”:0,“data”:“4 bytes”,“raw”:“12 bytes”}

[DEBUG] 2026-01-29 14:55:56 [RevvoxFlasher] [CMD] READ_REG (0x0a) params: {“dir”:0,“command”:10,“size”:4,“value”:0,“data”:“4 bytes”,“raw”:“12 bytes”}

[DEBUG] 2026-01-29 14:55:56 [RevvoxFlasher] Average read time: 18.67 ms over 54 reads.

[INFO] 2026-01-29 14:55:56 [ESP32][Revvox] prepare: reliability check OK, downloading stub…

[DEBUG] 2026-01-29 14:55:56 [RevvoxFlasher] [CMD] MEM_BEGIN (0x05) params: {“dir”:0,“command”:5,“size”:16,“value”:0,“data”:“16 bytes”,“raw”:“24 bytes”}

[DEBUG] 2026-01-29 14:55:56 [RevvoxFlasher] [CMD] MEM_DATA (0x07) params: {“dir”:0,“command”:7,“size”:268,“value”:28,“data”:“268 bytes”,“raw”:“276 bytes”}

[DEBUG] 2026-01-29 14:55:56 [RevvoxFlasher] [CMD] MEM_BEGIN (0x05) params: {“dir”:0,“command”:5,“size”:16,“value”:0,“data”:“16 bytes”,“raw”:“24 bytes”}

[DEBUG] 2026-01-29 14:55:56 [RevvoxFlasher] [CMD] MEM_DATA (0x07) params: {“dir”:0,“command”:7,“size”:5308,“value”:55,“data”:“5308 bytes”,“raw”:“5316 bytes”}

[DEBUG] 2026-01-29 14:55:56 [RevvoxFlasher] [CMD] MEM_END (0x06) params: {“dir”:0,“command”:6,“size”:8,“value”:0,“data”:“8 bytes”,“raw”:“16 bytes”}

[DEBUG] 2026-01-29 14:55:56 [RevvoxFlasher] Final MEM_END ACK

[DEBUG] 2026-01-29 14:55:56 [RevvoxFlasher] Stub loader executed successfully (received OHAI)

[DEBUG] 2026-01-29 14:55:56 [RevvoxFlasher] [CMD] SPI_SET_PARAMS (0x0b) params: {“dir”:0,“command”:11,“size”:24,“value”:0,“data”:“24 bytes”,“raw”:“32 bytes”}

[DEBUG] 2026-01-29 14:55:56 [RevvoxFlasher] SPI_SET_PARAMS configured

[INFO] 2026-01-29 14:55:56 [ESP32][Revvox] prepare: stub uploaded OK

[DEBUG] 2026-01-29 14:55:56 [RevvoxFlasher] [CMD] READ_REG (0x0a) params: {“dir”:0,“command”:10,“size”:4,“value”:0,“data”:“4 bytes”,“raw”:“12 bytes”}

[INFO] 2026-01-29 14:55:56 [ESP32][Revvox] readFlash: chip identified {“mac”:“f0:f5:bd:5d:06:c0”,“chip”:“esp32s3”,“flashSizeKb”:8192}

[INFO] 2026-01-29 14:55:56 [ESP32][Revvox] readFlash: reading flash {“totalBytes”:8388608}

[DEBUG] 2026-01-29 14:55:56 [RevvoxFlasher] ReadFlashSafe: Reading 8388608 bytes in 262144-byte blocks…

[DEBUG] 2026-01-29 14:55:56 [RevvoxFlasher] [CMD] READ_FLASH (0xd2) params: {“dir”:0,“command”:210,“size”:16,“value”:0,“data”:“16 bytes”,“raw”:“24 bytes”}

[DEBUG] 2026-01-29 14:56:01 [RevvoxFlasher] ReadFlash timing: 262144 bytes in 4410ms

[DEBUG] 2026-01-29 14:56:01 [RevvoxFlasher] Data rate: 0.06 MB/s (59443 B/s)

[DEBUG] 2026-01-29 14:56:01 [RevvoxFlasher] Packet latency: min=66ms, max=108ms, avg=68.6ms

[DEBUG] 2026-01-29 14:56:01 [RevvoxFlasher] Packets received: 64

[DEBUG] 2026-01-29 14:56:01 [RevvoxFlasher] ReadFlashSafe: Read 262144/8388608 bytes (3%)

[DEBUG] 2026-01-29 14:56:01 [RevvoxFlasher] [CMD] READ_FLASH (0xd2) params: {“dir”:0,“command”:210,“size”:16,“value”:0,“data”:“16 bytes”,“raw”:“24 bytes”}

[DEBUG] 2026-01-29 14:56:05 [RevvoxFlasher] ReadFlash timing: 262144 bytes in 4366ms

[DEBUG] 2026-01-29 14:56:05 [RevvoxFlasher] Data rate: 0.06 MB/s (60042 B/s)

[DEBUG] 2026-01-29 14:56:05 [RevvoxFlasher] Packet latency: min=66ms, max=97ms, avg=67.9ms

[DEBUG] 2026-01-29 14:56:05 [RevvoxFlasher] Packets received: 64

[DEBUG] 2026-01-29 14:56:05 [RevvoxFlasher] ReadFlashSafe: Read 524288/8388608 bytes (6%)

[DEBUG] 2026-01-29 14:56:05 [RevvoxFlasher] [CMD] READ_FLASH (0xd2) params: {“dir”:0,“command”:210,“size”:16,“value”:0,“data”:“16 bytes”,“raw”:“24 bytes”}

[DEBUG] 2026-01-29 14:56:10 [RevvoxFlasher] ReadFlash timing: 262144 bytes in 4380ms

[DEBUG] 2026-01-29 14:56:10 [RevvoxFlasher] Data rate: 0.06 MB/s (59850 B/s)

[DEBUG] 2026-01-29 14:56:10 [RevvoxFlasher] Packet latency: min=65ms, max=97ms, avg=68.2ms

[DEBUG] 2026-01-29 14:56:10 [RevvoxFlasher] Packets received: 64

[DEBUG] 2026-01-29 14:56:10 [RevvoxFlasher] ReadFlashSafe: Read 786432/8388608 bytes (9%)

[DEBUG] 2026-01-29 14:56:10 [RevvoxFlasher] [CMD] READ_FLASH (0xd2) params: {“dir”:0,“command”:210,“size”:16,“value”:0,“data”:“16 bytes”,“raw”:“24 bytes”}

[DEBUG] 2026-01-29 14:56:14 [RevvoxFlasher] ReadFlash timing: 262144 bytes in 4372ms

[DEBUG] 2026-01-29 14:56:14 [RevvoxFlasher] Data rate: 0.06 MB/s (59960 B/s)

[DEBUG] 2026-01-29 14:56:14 [RevvoxFlasher] Packet latency: min=65ms, max=103ms, avg=67.9ms

[DEBUG] 2026-01-29 14:56:14 [RevvoxFlasher] Packets received: 64

[DEBUG] 2026-01-29 14:56:14 [RevvoxFlasher] ReadFlashSafe: Read 1048576/8388608 bytes (13%)

[DEBUG] 2026-01-29 14:56:14 [RevvoxFlasher] [CMD] READ_FLASH (0xd2) params: {“dir”:0,“command”:210,“size”:16,“value”:0,“data”:“16 bytes”,“raw”:“24 bytes”}

[ERROR] 2026-01-29 14:57:18 [ESP32][Revvox] readFlash failed {}

[INFO] 2026-01-29 14:57:22 [ESP32][Revvox] Disconnect requested

[INFO] 2026-01-29 14:57:22 [ESP32][Revvox] Disconnected OK

I already tried two different UART´s. Always the same problem at slightly different percentages completed.

Do you have any advise?

pouyonsel · January 29, 2026, 8:00pm

Hi everyone,

I have the same issue.

I have tried different UARTs, different Cables and different Laptops (win11 and win10).

Connection works and I get the “waiting for download” in the serial monitor in ESPConnect.

Trying to read the flash in TeddyCloud fails after a timeout. Tried all different Baud rates.

Connection to ESP Connect works but I can only see 2 small partitions.

Connection to g3ggos ESP tool works and shows all partitions but can only download the files smaller than 1 MB. Everything above that fails after a timeout.

Cable connections are fine (Rx to Tx, Tx to RC, And to Gnd). UART ist set to 3.3 V. 3 pin connection is aligned. Tried both battery and AC. Correct driver is installed.

Interested to see if someone finds a solution.