Arducam MEGA Parser Timeout Error on UNO, ESP8266, ESP32; Pico4ML-Pro source code needed

SPI Cameras
1

I’m trying to get an Arducam MEGA 5MP SPI camera working but I’m completely stuck. The Arducam MEGA app does connect, but right after connecting I get this sequence:

AA message success
Parser Timeout Error
closed success

No stream, no image, nothing after that. Does anyone know what’s happening here?

2

Thanks for posting the exact output — that’s helpful. We’ve just updated the Host Communication Protocol page for the Arducam MEGA, including a clearer block diagram of the expected handshake. Can you have a look and cross-check it against what your host is doing?

https://www.arducam.com/docs/arducam-mega/arducam-mega-getting-started/packs/HostCommunicationProtocol.html#communication-protocol-block-diagram

A Parser Timeout Error generally means the host-side parser timed out before it could assemble a valid packet, so verifying the protocol sequence is a good first step.

3

Just to add, I get the exact same failure on UNO, ESP8266 and ESP32. It doesn’t seem to be tied to any one platform.

4

The weird part is these same Mega 5MP SPI cameras work fine on the PICO4ML-Pro TinyML RP2040 board. It’s only on other host platforms that they fail. I also can’t find the source code for the PICO4ML-Pro TinyML board anywhere — I want to run custom firmware on it with two cameras.

5

Thanks for the extra detail. So we can probably rule out the cameras themselves if they work on the Pico board. Can you list everything you’ve already tried — boards, cameras, computers, IDE versions — so we don’t go in circles?

6

Here’s what I’ve tried so far:

  • 2x ESP32
  • 2x ESP8266
  • 2x UNO
  • both of my 5MP MEGA cameras
  • two different computers
  • fresh install of Arduino IDE 2.1

Every single combination ends with the same Parser Timeout Error.

Also, could someone explain where that parser error message actually comes from, why it happens, and how to fix it? And is there a Mac version of the Arducam MEGA app? The one I have is Windows-only.

7

One more thing — the Arducam_Mega examples and application are based on the Arducam API and they seem to have bugs. Can I get a link to the source code, schematic, and pinout for the Pico4ML board so I can reuse it?

8

Here’s the Pico4ML example source code:

I’ve also attached the pinout definition image for reference. For the full schematic, you’ll need to reach out to UCTRONICS directly — they handle the schematic side.

9

Thanks, but the pinout you posted isn’t enough for what I need. I need to know exactly which pins Cam1, Cam2, Cam3, Cam4, the XP touch control chip, and the ESP32 connect to on the RP2040. Also the pins for the TFT and the microphone, and what TFT it actually is (an IL series panel?). Is there source code for this exact setup? I’d really rather not reverse engineer the whole board. I’ve attached a photo of the board.

10

To summarize where this stands: we haven’t pinned down the root cause of the Parser Timeout Error on the non-Pico hosts yet, so I don’t have a fix to hand right now. What we have so far is the updated Host Communication Protocol page and the Pico4ML example source on GitHub, plus the pinout image. For the board schematic, UCTRONICS is the contact. I’ll update this thread once we have more on the parser timeout.