Enabling DMX output on esp32s3 causes boot loop

[wilburCforce]

--------- Instructions --------
Please provide answers directly below each section.
--------- Instructions ---------

ESPixelStick Firmware Version
This was built from the main branch on 20260620

Hardware Version
seed studio esp32s3

Binary release or compiled yourself?
compiled myself

Operating System (and version)
win 11

Web Browser (and version)
chrome

Access Point

Describe the bug
Using just initial load without setting wifi or anything else (although it does it the same if wifi is configured) when you change any of the outputs to DMX the device enters a boot loop.
Guru Meditation Error: Core 1 panic'ed (Cache disabled but cached memory region accessed).

I'm trying to use the firmware as an ArtNet target to control DMX fixtures. This works quite well on the older firmware for the ESP8266 that I mocked it up on but in trying to minimize the footprint with the S3 I encountered this.

Log file attached.

logs.txt

[wilburCforce]

I should add, I also tried @MartinMueller2003 main branch but I couldn't get that to even flash the esp.

[wilburCforce]

and here is more useful log output from the debugger:
Guru Meditation Error: Core 1 panic'ed (Cache disabled but cached memory region accessed).

Core 1 register dump:
PC : 0x40374dad PS : 0x00060034 A0 : 0x8037505c A1 : 0x3fc988c0
#0 0x40374dad in c_OutputRmt::ISR_Handler(c_OutputRmt::isrTxFlags_t) at src/output/OutputRmtV4.cpp:383

A2 : 0x3d802da4 A3 : 0x00000000 A4 : 0x00000000 A5 : 0x00000001
A6 : 0x02c97494 A7 : 0x00ffffff A8 : 0xbad00bae A9 : 0x3fcec62c
A10 : 0x222c2232 A11 : 0x73616c66 A12 : 0x00000000 A13 : 0x3fcec5a0
A14 : 0x00000000 A15 : 0x3fcaa250 SAR : 0x0000001f EXCCAUSE: 0x00000007
EXCVADDR: 0x00000000 LBEG : 0x400570e8 LEND : 0x400570f3 LCOUNT : 0x00000000

Backtrace: 0x40374daa:0x3fc988c0 0x40375059:0x3fc988f0 0x40379c65:0x3fc98920 0x4037a7ed:0x3fc98940 0x403861e7:0x3fcec5d0 0x40377ed6:0x3fcec650 0x4209ca8f:0x3fcec690 0x420c8062:0x3fcec6c0 0x420c830e:0x3fcec6f0 0x420c9427:0x3fcec730 0x420c9997:0x3fcec7d0 0x420cb8c9:0x3fcec830 0x420c7530:0x3fcec880 0x420a2151:0x3fcec9b0 0x42115e15:0x3fcec9d0 0x421094ca:0x3fcec9f0 0x4207a742:0x3fceca80 0x420096ea:0x3fcecab0 0x420187eb:0x3fcecb70 0x420470aa:0x3fceccf0 0x42093c76:0x3fcecd70
#0 0x40374daa in c_OutputRmt::ISR_Handler(c_OutputRmt::isrTxFlags_t) at src/output/OutputRmtV4.cpp:382
#1 0x3fc988c0 in port_IntStack at ??:?
#2 0x40375059 in rmt_intr_handler(void*) at src/output/OutputRmtV4.cpp:146
#3 0x3fc988f0 in port_IntStack at ??:?
#4 0x40379c65 in shared_intr_isr at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/esp_hw_support/intr_alloc.c:407
#5 0x3fc98920 in port_IntStack at ??:?
#6 0x4037a7ed in xt_lowint1 at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/freertos/port/xtensa/xtensa_vectors.S:1118
#7 0x3fc98940 in port_IntStackTop at ??:?
#8 0x403861e7 in spi_flash_chip_winbond_read at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/spi_flash/spi_flash_chip_winbond.c:66
#9 0x40377ed6 in esp_flash_read at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/spi_flash/esp_flash_api.c:852
#10 0x4209ca8f in esp_partition_read at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/spi_flash/partition.c:424
#11 0x420c8062 in littlefs_esp_part_read at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/components/esp_littlefs/src/littlefs_esp_part.c:21
#12 0x420c830e in lfs_bd_read at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/components/esp_littlefs/src/littlefs/lfs.c:116
#13 0x420c9427 in lfs_dir_fetchmatch at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/components/esp_littlefs/src/littlefs/lfs.c:1153
#14 0x420c9997 in lfs_dir_find at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/components/esp_littlefs/src/littlefs/lfs.c:1536
#15 0x420cb8c9 in lfs_stat at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/components/esp_littlefs/src/littlefs/lfs.c:3825
(inlined by) lfs_stat at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/components/esp_littlefs/src/littlefs/lfs.c:5979
#16 0x420c7530 in vfs_littlefs_stat at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/components/esp_littlefs/src/esp_littlefs.c:1846
#17 0x420a2151 in esp_vfs_stat at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/vfs/vfs.c:580 (discriminator 3)
#18 0x42115e15 in stat at /builds/idf/crosstool-NG/.build/HOST-x86_64-w64-mingw32/xtensa-esp32s3-elf/src/newlib/newlib/libc/syscalls/sysstat.c:11
#19 0x421094ca in VFSImpl::open(char const*, char const*, bool) at .pio/packages/framework-arduinoespressif32/libraries/FS/src/vfs_api.cpp:44
#20 0x4207a742 in fs::FS::open(char const*, char const*, bool) at .pio/packages/framework-arduinoespressif32/libraries/FS/src/FS.cpp:234
#21 0x420096ea in c_FileMgr::SaveFlashFile(String const&, ArduinoJson::V743PB22::JsonDocument&) at src/FileMgr.cpp:853
#22 0x420187eb in c_WebMgr::CreateAdminInfoFile() at src/WebMgr.cpp:752 (discriminator 1)
#23 0x420470aa in setup() at src/main.cpp:265 (discriminator 19)
#24 0x42093c76 in loopTask(void*) at .pio/packages/framework-arduinoespressif32/cores/esp32/main.cpp:42

[MartinMueller2003]

That means that one of the functions called by the ISR is not actually in ISR memory,

[MartinMueller2003]

I just built and loaded my latest code on an ESP32=S3. Configured to output DMX for 64 channels. No reboots. On Saturday, June 20, 2026 at 11:52:15 PM EDT, wilburCforce ***@***.***> wrote: wilburCforce left a comment (forkineye/ESPixelStick#923) and here is more useful log output from the debugger: Guru Meditation Error: Core 1 panic'ed (Cache disabled but cached memory region accessed). Core 1 register dump: PC : 0x40374dad PS : 0x00060034 A0 : 0x8037505c A1 : 0x3fc988c0 #0 0x40374dad in c_OutputRmt::ISR_Handler(c_OutputRmt::isrTxFlags_t) at src/output/OutputRmtV4.cpp:383 A2 : 0x3d802da4 A3 : 0x00000000 A4 : 0x00000000 A5 : 0x00000001 A6 : 0x02c97494 A7 : 0x00ffffff A8 : 0xbad00bae A9 : 0x3fcec62c A10 : 0x222c2232 A11 : 0x73616c66 A12 : 0x00000000 A13 : 0x3fcec5a0 A14 : 0x00000000 A15 : 0x3fcaa250 SAR : 0x0000001f EXCCAUSE: 0x00000007 EXCVADDR: 0x00000000 LBEG : 0x400570e8 LEND : 0x400570f3 LCOUNT : 0x00000000 Backtrace: 0x40374daa:0x3fc988c0 0x40375059:0x3fc988f0 0x40379c65:0x3fc98920 0x4037a7ed:0x3fc98940 0x403861e7:0x3fcec5d0 0x40377ed6:0x3fcec650 0x4209ca8f:0x3fcec690 0x420c8062:0x3fcec6c0 0x420c830e:0x3fcec6f0 0x420c9427:0x3fcec730 0x420c9997:0x3fcec7d0 0x420cb8c9:0x3fcec830 0x420c7530:0x3fcec880 0x420a2151:0x3fcec9b0 0x42115e15:0x3fcec9d0 0x421094ca:0x3fcec9f0 0x4207a742:0x3fceca80 0x420096ea:0x3fcecab0 0x420187eb:0x3fcecb70 0x420470aa:0x3fceccf0 0x42093c76:0x3fcecd70 #0 0x40374daa in c_OutputRmt::ISR_Handler(c_OutputRmt::isrTxFlags_t) at src/output/OutputRmtV4.cpp:382 #1 0x3fc988c0 in port_IntStack at ??:? #2 0x40375059 in rmt_intr_handler(void*) at src/output/OutputRmtV4.cpp:146 #3 0x3fc988f0 in port_IntStack at ??:? #4 0x40379c65 in shared_intr_isr at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/esp_hw_support/intr_alloc.c:407 #5 0x3fc98920 in port_IntStack at ??:? #6 0x4037a7ed in xt_lowint1 at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/freertos/port/xtensa/xtensa_vectors.S:1118 #7 0x3fc98940 in port_IntStackTop at ??:? #8 0x403861e7 in spi_flash_chip_winbond_read at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/spi_flash/spi_flash_chip_winbond.c:66 #9 0x40377ed6 in esp_flash_read at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/spi_flash/esp_flash_api.c:852 #10 0x4209ca8f in esp_partition_read at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/spi_flash/partition.c:424 #11 0x420c8062 in littlefs_esp_part_read at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/components/esp_littlefs/src/littlefs_esp_part.c:21 #12 0x420c830e in lfs_bd_read at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/components/esp_littlefs/src/littlefs/lfs.c:116 #13 0x420c9427 in lfs_dir_fetchmatch at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/components/esp_littlefs/src/littlefs/lfs.c:1153 #14 0x420c9997 in lfs_dir_find at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/components/esp_littlefs/src/littlefs/lfs.c:1536 #15 0x420cb8c9 in lfs_stat at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/components/esp_littlefs/src/littlefs/lfs.c:3825 (inlined by) lfs_stat at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/components/esp_littlefs/src/littlefs/lfs.c:5979 #16 0x420c7530 in vfs_littlefs_stat at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/components/esp_littlefs/src/esp_littlefs.c:1846 #17 0x420a2151 in esp_vfs_stat at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/vfs/vfs.c:580 (discriminator 3) #18 0x42115e15 in stat at /builds/idf/crosstool-NG/.build/HOST-x86_64-w64-mingw32/xtensa-esp32s3-elf/src/newlib/newlib/libc/syscalls/sysstat.c:11 #19 0x421094ca in VFSImpl::open(char const*, char const*, bool) at .pio/packages/framework-arduinoespressif32/libraries/FS/src/vfs_api.cpp:44 #20 0x4207a742 in fs::FS::open(char const*, char const*, bool) at .pio/packages/framework-arduinoespressif32/libraries/FS/src/FS.cpp:234 #21 0x420096ea in c_FileMgr::SaveFlashFile(String const&, ArduinoJson::V743PB22::JsonDocument&) at src/FileMgr.cpp:853 #22 0x420187eb in c_WebMgr::CreateAdminInfoFile() at src/WebMgr.cpp:752 (discriminator 1) #23 0x420470aa in setup() at src/main.cpp:265 (discriminator 19) #24 0x42093c76 in loopTask(void*) at .pio/packages/framework-arduinoespressif32/cores/esp32/main.cpp:42 — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you were mentioned.Message ID: ***@***.***>

[wilburCforce]

I just built and loaded my latest code on an ESP32=S3. Configured to output DMX for 64 channels. No reboots.
On Saturday, June 20, 2026 at 11:52:15 PM EDT, wilburCforce @.***> wrote:

wilburCforce left a comment (forkineye/ESPixelStick#923)
and here is more useful log output from the debugger:
Guru Meditation Error: Core 1 panic'ed (Cache disabled but cached memory region accessed).
—
Reply to this email directly, view it on GitHub, or unsubscribe.
You are receiving this because you were mentioned.Message ID: @.***>

is that off your main branch? and are you using a seed studio esp32s3?
I tried that yesterday and it behaved the same as this repo.

[MartinMueller2003]

I have a devkit-C S3 platform.
Yes it is using my latest branch on github

[sethjohnson1]

I also got a boot loop when selecting DMX on my seeed studio s3. After some hunting around, I found this thread

Adding "-DCONFIG_SPI_MASTER_ISR_IN_IRAM=n" to the extra_flags in boards/seeed_xiao_esp32s3-custom.json let me select DMX without a boot loop, but I don't fully understand the implications of that flag and haven't had a chance to test it with an actual DMX device yet.

(After this line)

ESPixelStick/boards/seeed_xiao_esp32s3-custom.json

Line 14 in c5e1730

"-DARDUINO_EVENT_RUNNING_CORE=1"

[MartinMueller2003]

Adding that line will cause SPI based outputs to crash. I checked again today and I am NOT seeing the crash with the most recent build.

[wilburCforce]

ok, I pulled a fresh clone off your main branch.
I tried compiling with esp32s3_devkitc to match your test. the device has a smaller mem footprint though and won't boot with that build.
So I used the esp32s3_seeed_xiao which is what this hardware is.
I set the input to e1.31, no problem.
I set the output to DMX, if I use the default GPIO I lose the serial console because the UART conflict, however the device becomes unresponsive on save so I'm assuming it is looping.
If I change to GPIO 4 on D3, it allows me to save and you see the config save correctly in the log.
However, as soon as you click on home or anything else on the page, it begins the loop.

I let an AI agent run wild on it for a while the other night and it got it to be stable have a whole lot of IRAM work. (the code looks like garbage though as the prompts were not well formed or thoughtful) Even then, it appears the output wasn't enough voltage from this device to be able to swing my RS485 self adjusting board into output mode. So this whole thing may be a waste of time anyway.

Regardless, here is the trace info from the boot loop:
This is right after the save of the DMX output config:

[FileMgr] Configuration File: '/output_config.json.tmp' saved 1436 bytes.
[FileMgr] Configuration File: '/output_config.j36 bytes.
[FileMgr] Configuration File: '/output_config.json.tmp' sa36 bytes.
[FileMgr] Configuration Fil36 bytes.
[FileMgr] Configuration File: '/output_config.json.tmp' saved 1436 bytes.
6 bytes.
[ 50526][E][vfs_api.cpp:105] open(): /littlefs/output_config.json does not exist, no permits for creation
[Fs.
[FileMgr] Configuration File: '/fseqfilelist.json' saved 76 bytes.
[FileMgr] Configuration Fil6 bytes.
[FileMgr] Configuration File: '/input_config.json.tmp' saved 645 bytes.
[ 50763][E][vfs_api.cpp:105] open(): /littlefs/input_config.json does not exist, no permits for creation
[FileMgr] Configuration File: '/fseqfilelist.json' saved 76 bytes.
[FileMgr] Configuration File: '/config.json' loaded.
[FileMgr] Configuration File: '/input_config.json' loaded.
[FileMgr] Configuration File: '/output_config.json' loaded.
[OutputMgr]  Shutting Down 'Disabled' on Output: 0
[OutputMgr] 'DMX' Initialization for Output: 0
[ E1.31] Listening for 64 channels from Universe 1 to 1 on port 5568

As soon as I click home in the web UI I get this:

[OutputMgr] 'DMX' Initialization for Output: 0
[ E1.31] Listening for 64 channels from Universe 1 to 1 on port 5568
Guru Meditation Error: Core  1 panic'ed (Cache disabled but cached memory region accessed). 


Core  1 register dump:
PC      : 0x40374d99  PS      : 0x00060034  A0      : 0x80374fec  A1      : 0x3fc98850  
  #0  0x40374d99 in c_OutputRmt::ISR_Handler(c_OutputRmt::isrTxFlags_t) at .pio/packages/framework-arduinoespressif32/tools/sdk/esp32s3/include/hal/esp32s3/include/hal/rmt_ll.h:384
      (inlined by) c_OutputRmt::DisableRmtInterrupts() at include/output/OutputRmt.hpp:136
      (inlined by) c_OutputRmt::ISR_Handler(c_OutputRmt::isrTxFlags_t) at src/output/OutputRmtV4.cpp:385

A2      : 0x3d802db4  A3      : 0x00000000  A4      : 0x00000000  A5      : 0x00000001  
A6      : 0x02c97424  A7      : 0x00ffffff  A8      : 0x000000ad  A9      : 0x1300021c  
A10     : 0xbad00bad  A11     : 0x3fcbbc88  A12     : 0x00000000  A13     : 0x3fcbb1d0  
A14     : 0x00000000  A15     : 0x1300020c  SAR     : 0x0000001f  EXCCAUSE: 0x00000007  
EXCVADDR: 0x00000000  LBEG    : 0x400570e8  LEND    : 0x400570f3  LCOUNT  : 0x00000000  


Backtrace: 0x40374d96:0x3fc98850 0x40374fe9:0x3fc98880 0x40379bf5:0x3fc988b0 0x4037a77d:0x3fc988d0 0x403834a9:0x3fcbb200 0x40386191:0x3fcbb220 0x40377e66:0x3fcbb2a0 0x42099e5b:0x3fcbb2e0 0x420c542e:0x3fcbb310 0x420c56da:0x3fcbb340 0x420c575b:0x3fcbb380 0x420c581f:0x3fcbb3e0 0x420c84b2:0x3fcbb410 0x420c8d5f:0x3fcbb460 0x420c45c7:0x3fcbb480 0x4209f217:0x3fcbb4b0 0x4210ca4a:0x3fcbb4d0 0x4210caed:0x3fcbb500 0x42106010:0x3fcbb520 0x421068ed:0x3fcbb550 0x4208584f:0x3fcbb5e0 0x42121d5d:0x3fcbb620 0x42077c4b:0x3fcbb640 0x42077d63:0x3fcbb660 0x42012561:0x3fcbb6e0 0x42078fcb:0x3fcbb750 0x42078ffd:0x3fcbb780 0x42121e87:0x3fcbb7d0 0x4207c65f:0x3fcbb7f0 0x42080895:0x3fcbb810 0x42079b4d:0x3fcbb8a0 0x4207c65f:0x3fcbb8e0 0x42080895:0x3fcbb900 0x4207a2f6:0x3fcbb990 0x4207c146:0x3fcbb9d0 0x4207c203:0x3fcbba10 0x4207c4e1:0x3fcbba60 0x421050bb:0x3fcbba80 0x4210510a:0x3fcbbab0 0x42105224:0x3fcbbad0 0x42105301:0x3fcbbaf0
  #0  0x40374d96 in c_OutputRmt::ISR_Handler(c_OutputRmt::isrTxFlags_t) at src/output/OutputRmtV4.cpp:383
  #1  0x3fc98850 in port_IntStack at ??:?
  #2  0x40374fe9 in rmt_intr_handler(void*) at src/output/OutputRmtV4.cpp:146
  #3  0x3fc98880 in port_IntStack at ??:?
  #4  0x40379bf5 in shared_intr_isr at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/esp_hw_support/intr_alloc.c:407
  #5  0x3fc988b0 in port_IntStack at ??:?
  #6  0x4037a77d in _xt_lowint1 at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/freertos/port/xtensa/xtensa_vectors.S:1118
  #7  0x3fc988d0 in port_IntStackTop at ??:?
  #8  0x403834a9 in spimem_flash_ll_auto_resume_init at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/hal/esp32s3/include/hal/spimem_flash_ll.h:149
      (inlined by) spi_flash_hal_disable_auto_resume_mode at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/hal/spi_flash_hal_iram.c:180
      (inlined by) spi_flash_hal_device_config at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/hal/spi_flash_hal_common.inc:65
  #9  0x40386191 in spi_flash_chip_winbond_read at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/spi_flash/spi_flash_chip_winbond.c:69
  #10 0x40377e66 in esp_flash_read at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/spi_flash/esp_flash_api.c:852
  #11 0x42099e5b in esp_partition_read at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/spi_flash/partition.c:424
  #12 0x420c542e in littlefs_esp_part_read at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/components/esp_littlefs/src/littlefs_esp_part.c:21
  #13 0x420c56da in lfs_bd_read at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/components/esp_littlefs/src/littlefs/lfs.c:116
  #14 0x420c575b in lfs_dir_getslice at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/components/esp_littlefs/src/littlefs/lfs.c:724
  #15 0x420c581f in lfs_dir_get at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/components/esp_littlefs/src/littlefs/lfs.c:770
  #16 0x420c84b2 in lfs_file_opencfg_ at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/components/esp_littlefs/src/littlefs/lfs.c:3110
  #17 0x420c8d5f in lfs_file_open_ at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/components/esp_littlefs/src/littlefs/lfs.c:3199
      (inlined by) lfs_file_open at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/components/esp_littlefs/src/littlefs/lfs.c:6046
  #18 0x420c45c7 in vfs_littlefs_open at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/components/esp_littlefs/src/esp_littlefs.c:1427
  #19 0x4209f217 in esp_vfs_open at /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/vfs/vfs.c:399 (discriminator 3)
  #20 0x4210ca4a in _fopen_r at /builds/idf/crosstool-NG/.build/HOST-x86_64-w64-mingw32/xtensa-esp32s3-elf/src/newlib/newlib/libc/stdio/fopen.c:129
  #21 0x4210caed in fopen at /builds/idf/crosstool-NG/.build/HOST-x86_64-w64-mingw32/xtensa-esp32s3-elf/src/newlib/newlib/libc/stdio/fopen.c:168
  #22 0x42106010 in VFSFileImpl::VFSFileImpl(VFSImpl*, char const*, char const*) at .pio/packages/framework-arduinoespressif32/libraries/FS/src/vfs_api.cpp:299
  #23 0x421068ed in void __gnu_cxx::new_allocator<VFSFileImpl>::construct<VFSFileImpl, VFSImpl*, char const*&, char const*&>(VFSFileImpl*, VFSImpl*&&, char const*&, char const*&) at c:\users\micro\documents\repos\esppixelstick\espixelstick\.pio\packages\toolchain-xtensa-esp32s3\xtensa-esp32s3-elf\include\c++\8.4.0\ext/new_allocator.h:136
      (inlined by) void std::allocator_traits<std::allocator<VFSFileImpl> >::construct<VFSFileImpl, VFSImpl*, char const*&, char const*&>(std::allocator<VFSFileImpl>&, VFSFileImpl*, VFSImpl*&&, char const*&, char const*&) at c:\users\micro\documents\repos\esppixelstick\espixelstick\.pio\packages\toolchain-xtensa-esp32s3\xtensa-esp32s3-elf\include\c++\8.4.0\bits/alloc_traits.h:475
      (inlined by) std::_Sp_counted_ptr_inplace<VFSFileImpl, std::allocator<VFSFileImpl>, (__gnu_cxx::_Lock_policy)2>::_Sp_counted_ptr_inplace<VFSImpl*, char const*&, char const*&>(std::allocator<VFSFileImpl>, VFSImpl*&&, char const*&, char const*&) at c:\users\micro\documents\repos\esppixelstick\espixelstick\.pio\packages\toolchain-xtensa-esp32s3\xtensa-esp32s3-elf\include\c++\8.4.0\bits/shared_ptr_base.h:545
      (inlined by) std::__shared_count<(__gnu_cxx::_Lock_policy)2>::__shared_count<VFSFileImpl, std::allocator<VFSFileImpl>, VFSImpl*, char const*&, char const*&>(VFSFileImpl*&, std::_Sp_alloc_shared_tag<std::allocator<VFSFileImpl> >, VFSImpl*&&, char const*&, char const*&) at c:\users\micro\documents\repos\esppixelstick\espixelstick\.pio\packages\toolchain-xtensa-esp32s3\xtensa-esp32s3-elf\include\c++\8.4.0\bits/shared_ptr_base.h:677
      (inlined by) std::__shared_ptr<VFSFileImpl, (__gnu_cxx::_Lock_policy)2>::__shared_ptr<std::allocator<VFSFileImpl>, VFSImpl*, char const*&, char const*&>(std::_Sp_alloc_shared_tag<std::allocator<VFSFileImpl> >, VFSImpl*&&, char const*&, char const*&) at c:\users\micro\documents\repos\esppixelstick\espixelstick\.pio\packages\toolchain-xtensa-esp32s3\xtensa-esp32s3-elf\include\c++\8.4.0\bits/shared_ptr_base.h:1342
      (inlined by) std::shared_ptr<VFSFileImpl>::shared_ptr<std::allocator<VFSFileImpl>, VFSImpl*, char const*&, char const*&>(std::_Sp_alloc_shared_tag<std::allocator<VFSFileImpl> >, VFSImpl*&&, char const*&, char const*&) at c:\users\micro\documents\repos\esppixelstick\espixelstick\.pio\packages\toolchain-xtensa-esp32s3\xtensa-esp32s3-elf\include\c++\8.4.0\bits/shared_ptr.h:359
      (inlined by) std::shared_ptr<VFSFileImpl> std::allocate_shared<VFSFileImpl, std::allocator<VFSFileImpl>, VFSImpl*, char const*&, char const*&>(std::allocator<VFSFileImpl> const&, VFSImpl*&&, char const*&, char const*&) at c:\users\micro\documents\repos\esppixelstick\espixelstick\.pio\packages\toolchain-xtensa-esp32s3\xtensa-esp32s3-elf\include\c++\8.4.0\bits/shared_ptr.h:706
      (inlined by) std::shared_ptr<VFSFileImpl> std::make_shared<VFSFileImpl, VFSImpl*, char const*&, char const*&>(VFSImpl*&&, char const*&, char const*&) at c:\users\micro\documents\repos\esppixelstick\espixelstick\.pio\packages\toolchain-xtensa-esp32s3\xtensa-esp32s3-elf\include\c++\8.4.0\bits/shared_ptr.h:722
      (inlined by) VFSImpl::open(char const*, char const*, bool) at .pio/packages/framework-arduinoespressif32/libraries/FS/src/vfs_api.cpp:47
  #24 0x4208584f in LittleFSImpl::exists(char const*) at .pio/packages/framework-arduinoespressif32/libraries/LittleFS/src/LittleFS.cpp:48
  #25 0x42121d5d in fs::FS::exists(char const*) at .pio/packages/framework-arduinoespressif32/libraries/FS/src/FS.cpp:242
  #26 0x42077c4b in fs::FS::exists(String const&) at .pio/packages/framework-arduinoespressif32/libraries/FS/src/FS.cpp:247
  #27 0x42077d63 in AsyncWebServerRequest::send(fs::FS&, String const&, char const*, bool, std::function<String (String const&)>) at .pio/libdeps/esp32s3_seeed_xiao/ESPAsyncWebServer/src/AsyncWebServerRequest.cpp:23
  #28 0x42012561 in std::_Function_handler<void (AsyncWebServerRequest*), c_WebMgr::init()::{lambda(AsyncWebServerRequest*)#12}>::_M_invoke(std::_Any_data const&, AsyncWebServerRequest*&&) at src/WebMgr.cpp:381
      (inlined by) _M_invoke at c:\users\micro\documents\repos\esppixelstick\espixelstick\.pio\packages\toolchain-xtensa-esp32s3\xtensa-esp32s3-elf\include\c++\8.4.0\bits/std_function.h:297
  #29 0x42078fcb in std::function<void (AsyncWebServerRequest*)>::operator()(AsyncWebServerRequest*) const at c:\users\micro\documents\repos\esppixelstick\espixelstick\.pio\packages\toolchain-xtensa-esp32s3\xtensa-esp32s3-elf\include\c++\8.4.0\bits/std_function.h:687
  #30 0x42078ffd in AsyncCallbackWebHandler::handleRequest(AsyncWebServerRequest*) at .pio/libdeps/esp32s3_seeed_xiao/ESPAsyncWebServer/src/WebHandlers.cpp:314
  #31 0x42121e87 in std::_Function_handler<void (), AsyncWebServerRequest::_runMiddlewareChain()::{lambda()#2}::operator()() const::{lambda()#1}>::_M_invoke(std::_Any_data const&) at .pio/libdeps/esp32s3_seeed_xiao/ESPAsyncWebServer/src/WebRequest.cpp:701
      (inlined by) _M_invoke at c:\users\micro\documents\repos\esppixelstick\espixelstick\.pio\packages\toolchain-xtensa-esp32s3\xtensa-esp32s3-elf\include\c++\8.4.0\bits/std_function.h:297
  #32 0x4207c65f in std::function<void ()>::operator()() const at c:\users\micro\documents\repos\esppixelstick\espixelstick\.pio\packages\toolchain-xtensa-esp32s3\xtensa-esp32s3-elf\include\c++\8.4.0\bits/std_function.h:687
  #33 0x42080895 in AsyncMiddlewareChain::_runChain(AsyncWebServerRequest*, std::function<void ()>) at .pio/libdeps/esp32s3_seeed_xiao/ESPAsyncWebServer/src/Middleware.cpp:56
  #34 0x42079b4d in std::_Function_handler<void (), AsyncWebServerRequest::_runMiddlewareChain()::{lambda()#2}>::_M_invoke(std::_Any_data const&) at .pio/libdeps/esp32s3_seeed_xiao/ESPAsyncWebServer/src/WebRequest.cpp:700
      (inlined by) _M_invoke at c:\users\micro\documents\repos\esppixelstick\espixelstick\.pio\packages\toolchain-xtensa-esp32s3\xtensa-esp32s3-elf\include\c++\8.4.0\bits/std_function.h:297
  #35 0x4207c65f in std::function<void ()>::operator()() const at c:\users\micro\documents\repos\esppixelstick\espixelstick\.pio\packages\toolchain-xtensa-esp32s3\xtensa-esp32s3-elf\include\c++\8.4.0\bits/std_function.h:687
  #36 0x42080895 in AsyncMiddlewareChain::_runChain(AsyncWebServerRequest*, std::function<void ()>) at .pio/libdeps/esp32s3_seeed_xiao/ESPAsyncWebServer/src/Middleware.cpp:56
  #37 0x4207a2f6 in AsyncWebServerRequest::_runMiddlewareChain() at .pio/libdeps/esp32s3_seeed_xiao/ESPAsyncWebServer/src/WebRequest.cpp:698 (discriminator 4)
  #38 0x4207c146 in AsyncWebServerRequest::_parseLine() at .pio/libdeps/esp32s3_seeed_xiao/ESPAsyncWebServer/src/WebRequest.cpp:683
  #39 0x4207c203 in AsyncWebServerRequest::_onData(void*, unsigned int) at .pio/libdeps/esp32s3_seeed_xiao/ESPAsyncWebServer/src/WebRequest.cpp:158
  #40 0x4207c4e1 in std::_Function_handler<void (void*, AsyncClient*, void*, unsigned int), AsyncWebServerRequest::AsyncWebServerRequest(AsyncWebServer*, AsyncClient*)::{lambda(void*, AsyncClient*, void*, unsigned int)#5}>::_M_invoke(std::_Any_data const&, void*&&, AsyncClient*&&, std::_Any_data const&, unsigned int&&) at .pio/libdeps/esp32s3_seeed_xiao/ESPAsyncWebServer/src/WebRequest.cpp:70
      (inlined by) _M_invoke at c:\users\micro\documents\repos\esppixelstick\espixelstick\.pio\packages\toolchain-xtensa-esp32s3\xtensa-esp32s3-elf\include\c++\8.4.0\bits/std_function.h:297
  #41 0x421050bb in std::function<void (void*, AsyncClient*, void*, unsigned int)>::operator()(void*, AsyncClient*, void*, unsigned int) const at c:\users\micro\documents\repos\esppixelstick\espixelstick\.pio\packages\toolchain-xtensa-esp32s3\xtensa-esp32s3-elf\include\c++\8.4.0\bits/std_function.h:687
  #42 0x4210510a in AsyncClient::_recv(tcp_pcb*, pbuf*, signed char) at .pio/libdeps/esp32s3_seeed_xiao/AsyncTCP@src-4025de6eb54e3d61260b0b7bdb363ba6/src/AsyncTCP.cpp:1068
  #43 0x42105224 in AsyncTCP_detail::handle_async_event(lwip_tcp_event_packet_t*) at .pio/libdeps/esp32s3_seeed_xiao/AsyncTCP@src-4025de6eb54e3d61260b0b7bdb363ba6/src/AsyncTCP.cpp:293
  #44 0x42105301 in _async_service_task(void*) at .pio/libdeps/esp32s3_seeed_xiao/AsyncTCP@src-4025de6eb54e3d61260b0b7bdb363ba6/src/AsyncTCP.cpp:328





ELF file SHA256: 7cf578c8acd5fb86

E (845) esp_core_dump_flash: Core dump flash config is corrupted! CRC=0x7bd5c66f instead of 0x0
Rebooting...

[wilburCforce]

stuck a better prompt on it and got it working.
Caveat: I'm not versed in C++, mostly scripting languages for me.

it made two minor additions but it seems potentially buggy so it's probably not a good patch.

In OutputMgr.cpp added:

#if defined(ARDUINO_ARCH_ESP32)
    #include <esp_heap_caps.h>
#endif

and then around line 250:

c_OutputMgr::c_OutputMgr ()
{
    ConfigFileName = String ("/") + String (CN_output_config) + CN_Dotjson;

    // clear the input data buffer
    #if defined(ARDUINO_ARCH_ESP32)
    // RMT ISR consumes this buffer; keep it in internal RAM so it remains accessible while cache is disabled.
    pOutputBuffer = reinterpret_cast<uint8_t*>(heap_caps_malloc(GetBufferSize() + 1, MALLOC_CAP_INTERNAL | MALLOC_CAP_8BIT));
    #else
    pOutputBuffer = (uint8_t*)malloc(GetBufferSize() + 1);
    #endif // defined(ARDUINO_ARCH_ESP32)

    if(nullptr == pOutputBuffer)
    {
        String Reason = F("ERROR: Could not allocate output buffer in internal RAM. Rebooting");
        RequestReboot(Reason, 100000);
        return;
    }

    memset(pOutputBuffer, 0, GetBufferSize());

it's probably a terrible patch

[MartinMueller2003]

This change should not make a difference. PSRAM is disabled in the build, making internal RAM the only RAM in the system.
I just looked in the board definition and only the internal ram is enabled and the full 8M flash is available.

I am purchasing a seeed device so I can take a closer look at this.

[MartinMueller2003]

This error is the one that comes out when an ISR tries to execute code that is not marked as an ISR and is not stored in internal flash memory
Guru Meditation Error: Core 1 panic'ed (Cache disabled but cached memory region accessed).

The error you get when trying to access data in PSRAM when you are in an ISR is different.

[wilburCforce]

I am purchasing a seeed device so I can take a closer look at this.

There is a prime day deal for a 3 pack that is $5 off right now
Do you have a link where I can buy you a coffee? Happy to support the cause and really appreciate you taking a look at this.