UNO R4 WiFi Cloud "Bus fault" Help Please!

Official Hardware Classic UNO R4 WiFi
1

Hi all,

Recently I bought a new UNO R4 WiFi for a project with Arduino Cloud, and it was working till today where I've been getting Mqttbroker issues, and was unable to connect to the cloud. Thus, I tried to reupdate the firmware using the IDE method, and tried to reflash 0.4.1 and 0.3, which both failed. I tried to reupload an original sketch after creating a thing on arduino cloud (bare bones code to connect to the cloud). This started giving me this error in serial monitor:

SHA256: 0 bytes (of 0) read

ArduinoIoTCloudTCP::begin could not read device id.

***** Arduino IoT Cloud - configuration info *****

Device ID:

MQTT Broker: iot.arduino.cc:8883

WiFi.status(): 0

Current WiFi Firmware: 0.4.1

Firmware name: "C:\Users\admin\AppData\Local\Temp\arduino\sketches\3195BCE7394DE5B4C9296055FAF6B006/Capstone_apr17a.ino", compiled on: Apr 18 2024

Fault on interrupt or bare metal(no OS) environment
===== Thread stack information =====
  addr: 20007ec8    data: 20000c50
  addr: 20007ecc    data: 0000587f
  addr: 20007ed0    data: 00000000
  addr: 20007ed4    data: 00012c79
  addr: 20007ed8    data: 0001ced9
  addr: 20007edc    data: 40046f00
  addr: 20007ee0    data: 00000000
  addr: 20007ee4    data: 00012cb7
  addr: 20007ee8    data: 0001ced9
  addr: 20007eec    data: 0000c5bf
  addr: 20007ef0    data: 0001ced9
  addr: 20007ef4    data: 0000ffcb
  addr: 20007ef8    data: 0000ffc1
  addr: 20007efc    data: 00002599
====================================
=================== Registers information ====================
  R0 : 00000000  R1 : 20002c9c  R2 : 20002ca8  R3 : 762fbb35
  R12: 20007d73  LR : 0000b2bf  PC : 762fbb34  PSR: a10f0000
==============================================================
Bus fault is caused by instruction access violation
Show more call stack info by run: addr2line -e "C:\Users\admin\AppData\Local\Temp\arduino\sketches\3195BCE7394DE5B4C9296055FAF6B006/Capstone_apr17a.ino".elf -a -f 762fbb34 0000b2be 0000587e 00012c78 00012cb6 0000c5be 0000ffca 0000ffc0

Sometimes it also says "Memory management fault is caused by instruction access violation"

I've also tried to manually reflash the firmware using espflash from this guide.

but still receive the same error. Using example code from the ledmatrix works though.

Any help would be greatly appreciated. Thanks!

3

Hi, I encounter the same error as you.
Have you found a solution ?

4

Very similar situation here. Was starting to blame myself as it was working fine last week, but nice to see I'm not alone. Works normally under the IDE but try to connect to the cloud or run the cloud blink sketch and I get similar output to the others, including a comment "could not read device id.

Any ideas out there?

5

Hey all, unfortunately, I could not find any solutions for this as of now. Seems like the Arduino staffs are also unable to help. Posted this on the official discord thread as well, and no one, including the Arduino staff, knows how to fix this. I emailed to the supplier I bought mine from, and their engineer suspected that it is probably a "defect in the memory level."

6

Not directly the answer to this problem.. but some help..Follow the advice to use addr2line -e .......

Also see another topic where this helped out someone with a different memory problem: Bus fault is caused by precise data access violation r4 WIFI - #4 by paulvha