... NRF_SCK GPIO6: Nrf_SCK
GPIO7:NRF_MOSI GPIO7: Nrf_Mosi
GPIO8:NRF_MISO GPIO8: Nrf_MISO
GPIO9:NRF_IRQ GPIO9: Nrf IRQ
GPIO10:ESP_RXD
GPIO11:ESP_TXD
GPIO12:I2S_DI
GPIO13:I2S_WS
GPIO14:I2S_BCK
XTAL_32K_P:DVP_D7
XTAL_32K_N:DVP_D6
GPIO17:DVP_D2 GPIO17: DVP_D2
GPIO18:DVP_D5 GPIO18: DVP_D5
GPIO19:DVP_D3 ...

... LCD/nRF24） 共用 SPI 总线：
SPICLK、SPICS0（LCD 片选）、SPIQ (MOSI)、SPID (MISO)
nRF24L01 GPIO5 (CS)、GPIO6 (SCK)、GPIO7 (MOSI)、GPIO8 (MISO)
其他 I²C（GPIO1/2）、I²S（GPIO12–14, 38）、DVP 摄像头（GPIO3,4,17–21 等）
⚠️ 关键疑点： SD 卡的时钟信号 TF_CLK 被同时连接到 MTDI 和 GPIO45，这可能违反了 ESP32-S3 的引脚复用规则，导致未定义行为。
📦 软件环境
* ESP-IDF 版本：v5.5.1（官方正式版 ...

... GPIO2:I2C_SCL
GPIO3:DVP_PCLK
GPIO4:DVP_XCLK
GPIO5:NRF_CS
GPIO6:NRF_SCK
GPIO7:NRF_MOSI
GPIO8:NRF_MISO
GPIO9:NRF_IRQ
GPIO10:ESP_RXD
GPIO11:ESP_TXD
GPIO12:I2S_DI
GPIO13:I2S_WS
GPIO14:I2S_BCK
XTAL_32K_P:DVP_D7
XTAL_32K_N:DVP_D6
GPIO17:DVP_D2
GPIO18:DVP_D5
GPIO19:DVP_D3
GPIO20:DVP_D4
GPIO21:DVP_D1 ...

... Red, green, and blue pins for PWM control
const int redPin = 13; // 13 corresponds to GPIO13
const int greenPin = 12; // 12 corresponds to GPIO12
const int bluePin = 14; // 14 corresponds to GPIO14

// Setting PWM frequency, channels and bit resolution
const int freq = 5000;
const int ...

... board design that uses the ESP32-WROOM-32E module.
I am encountering strange problems between the v3.0 and v3.1 versions of the ESP32.
I am using GPIO12 and GPIO13 as a secondary I2C bus. I have 10K pullup resistors to 3.3V and the I2C bus is connected to 2 x ADS1115 ADC chips running at 5V. At idle ...

... is DIO and the boot message is DIO.
The code runs fine, just can´t do any OTA updates or set any values in nv storage with anything connected to GPIO12.

I have now moved my SCL pin to GPIO14, leaving GPIO12 disconnected and everything works, OTA upgrades and nv changes.

I have 4 identical boards ...

gpio12 is a strapping pin, so it is important that the voltage be consistent (low) at boot.
You can turn this behavior off, and force the SDIO voltage to 3V3 by burning an efuse.

... board design that uses the ESP32-WROOM-32E module.
I am encountering strange problems between the v3.0 and v3.1 versions of the ESP32.
I am using GPIO12 and GPIO13 as a secondary I2C bus. I have 10K pullup resistors to 3.3V and the I2C bus is connected to 2 x ADS1115 ADC chips running at 5V. At idle ...

... GPIO11 | GPIO6 | GPIO19 | GPIO25 |
* +--------------+---------+-------+----------+----------+----------+----------+----------+
* | DO (MISO) | GPIO12 | GPIO19| GPIO37 | GPIO13 | GPIO5 | GPIO20 | GPIO11 ...

1. There are no constraints for GPIO12, GPIO13 so its safe to use them for i2c
Strapping pins for S3 are, according to the datasheet, GPIO 0, 3 45 and 46
2. Internal pull-up/down, according to the same data sheet is 45k, so too high for I2C