I2S Class missing from machine using ESP32-C6

[steve1780]

Trying to use the I2S class that is normally found in machine.
Did it move?
Using ESP32_GENERIC_C6-20250415-v1.25.0.bin on a XIAO ESP-32-C6

[ricksorensen]

For some reason it is turned off in the ESP32_GENERIC_C6 build. See ports\esp32\boards\ESP32_GENERIC_C6\mpconfigbard.h and line:

#define MICROPY_PY_MACHINE_I2S              (0)

This used to be the case for ESP32_GENERIC_C3 also, but that setting is removed. The default is defined in ports\esp32\mpconfigboard.h and uses the epressif IDF settings for each chip variant. Set this define to 1 and rebuilding should give you the I2S module.

[robert-hh]

Set this define to 1 and rebuilding should give you the I2S module.

Yep. That builds and makes I2S available in machine. I did not try, if it works.

[steve1780]

I was able to build a ESP32_GENERIC_C6 successfully ( I think the I2S in in the build, I noticed that the module was compiled: micropython/extmod/machine_i2s.c.obj) but have run into an invalid image block. ets_main.c 331 with the following details:

ESP-ROM:esp32c6-20220919
Build:Sep 19 2022
rst:0x7 (TG0_WDT_HPSYS),boot:0x1e (SPI_FAST_FLASH_BOOT)
Saved PC:0x40018bea
SPIWP:0xee
mode:DIO, clock div:2
load:0x42180020,len:0x42664
load:0x40800000,len:0xd98c
load:0x42000020,len:0x17d8c4
Invalid image block, can't boot.
ets_main.c 331 
ESP-ROM:esp32c6-20220919
Build:Sep 19 2022
rst:0x7 (TG0_WDT_HPSYS),boot:0x1e (SPI_FAST_FLASH_BOOT)
Saved PC:0x40018bea
SPIWP:0xee
mode:DIO, clock div:2
load:0x42180020,len:0x42664
load:0x40800000,len:0xd98c
load:0x42000020,len:0x17d8c4
Invalid image block, can't boot.
ets_main.c 331 
ESP-ROM:esp32c6-20220919
Build:Sep 19 2022
rst:0x7 (TG0_WDT_HPSYS),boot:0x1e (SPI_FAST_FLASH_BOOT)
Saved PC:0x40018bea
SPIWP:0xee
mode:DIO, clock div:2
load:0x42180020,len:0x42664

bin file is roughly the same size as the recent generic release. First time I've tried building mp. Did I miss a step?

[ricksorensen]

Sorry- I do not have a C6 to experiment with.

…

On Fri, Apr 18, 2025 at 4:06 PM Steve Case ***@***.***> wrote: I was able to build a ESP32_GENERIC_C6 successfully ( I think the I2S in in the build, I noticed that the module was compiled: micropython/extmod/machine_i2s.c.obj) but have run into an invalid image block. ets_main.c 331 with the following details: ESP-ROM:esp32c6-20220919 Build:Sep 19 2022 rst:0x7 (TG0_WDT_HPSYS),boot:0x1e (SPI_FAST_FLASH_BOOT) Saved PC:0x40018bea SPIWP:0xee mode:DIO, clock div:2 load:0x42180020,len:0x42664 load:0x40800000,len:0xd98c load:0x42000020,len:0x17d8c4 Invalid image block, can't boot. ets_main.c 331 ESP-ROM:esp32c6-20220919 Build:Sep 19 2022 rst:0x7 (TG0_WDT_HPSYS),boot:0x1e (SPI_FAST_FLASH_BOOT) Saved PC:0x40018bea SPIWP:0xee mode:DIO, clock div:2 load:0x42180020,len:0x42664 load:0x40800000,len:0xd98c load:0x42000020,len:0x17d8c4 Invalid image block, can't boot. ets_main.c 331 ESP-ROM:esp32c6-20220919 Build:Sep 19 2022 rst:0x7 (TG0_WDT_HPSYS),boot:0x1e (SPI_FAST_FLASH_BOOT) Saved PC:0x40018bea SPIWP:0xee mode:DIO, clock div:2 load:0x42180020,len:0x42664 bin file is roughly the same size as the recent generic release. First time I've tried building mp. Did I miss a step? — Reply to this email directly, view it on GitHub <#17151 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AA5QPQGOXCZ4LD23D25QKU322FSLZAVCNFSM6AAAAAB3LQ6I6GVHI2DSMVQWIX3LMV43URDJONRXK43TNFXW4Q3PNVWWK3TUHMYTEOBYGE3DOMA> . You are receiving this because you commented.Message ID: ***@***.*** com>

-- Rick Sorensen ***@***.*** 651-470-5511

[steve1780]

I understand.

Since I'm new to this, I think I'll first verify that I'm able to correctly build a generic ESP32 . After that I'll try to look for other settings that may interfere with the capabilities of the particular XIAO C6.

Any other suggestions would be appreciated.

[Josverl]

Using mpbuild can save a lot of time and setup headaches.

https://github.com/mattytrentini/mpbuild?tab=readme-ov-file#mpbuild

[steve1780]

I'll take a look. Thanks.

[steve1780]

I was able to add I2S to the ESP_GENERIC_C6 build. Setting the

#define MICROPY_PY_MACHINE_I2S (1)

worked.
Prior issue was due to the fact I flashed micropython.bin instead of firmware.bin. Rookie mistake. I2S is now present in machine.

So is this a bug? I don't feel like I should do a PR unless it is the only way it will get picked up.

[steve1780]

Verified operation on XIAO ESP32-C6 with following pinout. Using Mike Teachmans I2S examples as test cases. I2S Board was generic PCM5102 audio generator with 3.5mm output.

PCM5102 Signal Name	Xiao C6 Signal	Example Code Pin
Vin	3V3
Gnd	Gnd
SCK	Gnd
BCK	GPIO22	SCK_PIN = 22
LCK/RCK	GPIO23	WS_PIN = 23
DIN	GPIO16	SD_PIN = 16

[jimisola]

Great. I'm stumbled on this lack of I2S for C6 as well. Can you provide a PR so that it gets into the main build?
Is your build available somewhere. Otherwise, I'll start looking at compiling it myself.

[jimisola]

I have created a PR for this issue: #17644

[steve1780]

Thanks for doing the PR. I still have the XIAO versions of the -C6 if any additional testing needs to be done.

[jimisola]

I would appreciate if you can test if it works for you. I'm unable to get it to work for me. Although, I'm expecting it to be my code it would be nice to out my PR.

[jimisola]

What do you use for playback. I have a PCM5102A and I'm starting to suspect that I have the same issue as here