ESP32 Forum

Posted: **Fri Nov 22, 2024 7:55 pm**

I'm experiencing issues with the TWAI driver installation on an ESP32-S3 when trying to enable IRAM functionality. The driver works perfectly without IRAM flags but fails with error 0x102 when IRAM is enabled.

Hardware Setup

- ESP32-S3
- SN65HVD230 CAN transceiver
- Standard CAN bus termination (120Ω)
- Operating at 250 kbit/s

Implementation Details
Working Configuration (without IRAM):

Code: Select all

twai_general_config_t g_config = TWAI_GENERAL_CONFIG_DEFAULT(GPIO_NUM_14, GPIO_NUM_13, TWAI_MODE_NORMAL);
g_config.rx_queue_len = 64;
g_config.tx_queue_len = 32;
g_config.intr_flags = ESP_INTR_FLAG_LEVEL1;  // Works fine

Failing Configuration (with IRAM):

Code: Select all

g_config.intr_flags = ESP_INTR_FLAG_LEVEL1 | ESP_INTR_FLAG_IRAM;  // Fails with 0x102

Steps Taken:

1. Implemented proper DRAM data structures:

Code: Select all

volatile isr_data_t g_isr_data __attribute__((section(".dram1.data")));

2. Minimized ISR to rule out complexity issues:

Code: Select all

void IRAM_ATTR twai_isr_handler(void* arg) {
    // Even empty ISR fails
}

3. Added all necessary build flags:

Code: Select all

build_flags = 
    -DCONFIG_TWAI_ISR_IN_IRAM=1
    -DCONFIG_TWAI_ERRATA_FIX_RX_FRAME_INVALID=1
    -DCONFIG_TWAI_ERRATA_FIX_RX_FIFO_CORRUPT=1
    -DCONFIG_TWAI_ERRATA_FIX_BUS_OFF_REC=1
    -DCONFIG_TWAI_ERRATA_FIX_TX_INTR_LOST=1

Current Status

- Driver installation fails with error 0x102 only when IRAM flags are enabled
- All C++ bindings have been minimized
- ISR and data structures are properly placed in IRAM/DRAM
- Even a minimal implementation fails

Any insights into why the TWAI driver installation fails with IRAM enabled would be greatly appreciated.

ESP32 Forum

TWAI Driver Installation Fails with IRAM Enabled on ESP32-S3

TWAI Driver Installation Fails with IRAM Enabled on ESP32-S3