ESP32 S2 crash in static void IRAM_ATTR uart_intr_handle()

[chrisDupuis]

Crash with ESP32 S2 mini.

(Code is running on ESP32)

Someone have test on ESP32 S2 ? Any idea how to solve that ?

[ericlangel]

i dont have a S2 for testing

interesting that it is running on ESP32

which ESP32 Hardware Core Version? can u use the Exception decoder?

[chrisDupuis]

S2 Mini V1.0.0,

Hailege 3pcs ESP32 S2 Mini WiFi Development Board WIFI IOT Wireless Board Based on ESP32-S2FN4R2 ESP32-S2 4MB Flash Type-C MicroPython Arduino Compatible

I have no exception shown, only constantly rebooting...

[ericlangel]

I need the version of your ESP32 arduino core version is it already 3.0.0? or 2.0.16? or?

[chrisDupuis]

I use 2.0.16 In 3.0.0 I can't compile, error...

[ericlangel]

did you had a look at #44 ?

there are several reasons for crashing. It's hard to get the right one without exception decoder i could try to get a S2 Board, but i need some time to rework the code

there are several known issues, but i had no time for fix

[chrisDupuis]

Yes I use this topic and done some test since 3 days.

If I remove ESP_ERROR_CHECK(uart_isr_register(uart_num, uart_intr_handle, NULL, ESP_INTR_FLAG_IRAM, 0 /*handle_console*/)); No crash.

If I return in ISR uart, then crash.

static void IRAM_ATTR uart_intr_handle(void *arg) { uint16_t status = UART1.int_st.val; // read UART interrupt Status // status = UART1.int_st.val; // read UART interrupt Status uart_clear_intr_status(uart_num, UART_RXFIFO_FULL_INT_CLR | UART_RXFIFO_TOUT_INT_CLR); uart_clear_intr_status(uart_num, status);

return; }

[ericlangel]

ESP_ERROR_CHECK(uart_isr_register(uart_num, uart_intr_handle, NULL, ESP_INTR_FLAG_IRAM, 0 /handle_console/));

this call register the function uart_intr_handle to the Interrupt without this, the handler is never called so of course there is no Crash

you could try to register the function without ESP_INTR_FLAG_IRAM

[chrisDupuis]

Same crash without ESP_INTR_FLAG_IRAM.

I try to have very simple uart_intr_handle with minimum code, in ordre to not have crash/reboot.

[chrisDupuis]

What about that for minimum code

static void IRAM_ATTR uart_intr_handle(void *arg)
{
  uart_clear_intr_status(uart_num, UART_RXFIFO_FULL_INT_CLR | UART_RXFIFO_TOUT_INT_CLR);
  return;
}

[chrisDupuis]

One more, info, If no SBUS2 signal, no crash.

[ericlangel]

Ok lets try to work it out.

• No SBUS Signal no crash. Thats right. without SBUS signal the UART Interrupt is never executed

please uncomment the following lines/functions one by one and report back

• disable_receiving(); line321
• start_transmit_sequencer(((rxbuf[24]&0x30) >> 4)); line 330
• pinMatrixOutDetach(tx_pin,false,true); line265

the first 2 are working with the Timer, and i'am sure it is more or less a Timer Problem, but who knows

[chrisDupuis]

Test comment this line:

disable_receiving(); line321 => reboot start_transmit_sequencer(((rxbuf[24]&0x30) >> 4)); line 330 => reboot pinMatrixOutDetach(tx_pin,false,true); line265 => reboot

[chrisDupuis]

On more info, with the same module and pin assignment, I have test with iBus telemetry, and it s running ok https://github.com/bmellink/IBusBM

So for me the hardware, and wire is ok.

[chrisDupuis]

I add a rtc_get_reset_reason, print_reset_reason, and the cause is SW_RESET, RESET_REASON = 3

[ericlangel]

Test comment this line:

disable_receiving(); line321 => reboot start_transmit_sequencer(((rxbuf[24]&0x30) >> 4)); line 330 => reboot pinMatrixOutDetach(tx_pin,false,true); line265 => reboot

And all 3 disabled together?

[ericlangel]

here is the answer: Link

in the last comment

could you try to change: rxbuf[buffer_index] = UART1.fifo.rw_byte; // read all bytes

to

rxbuf[buffer_index] = READ_PERI_REG(UART_FIFO_AHB_REG(1)); // read all bytes

But there seems to be a bigger issue with the UART Periph on S2. So maybe its not crashing any more but UART is not read correctly

[chrisDupuis]

all 3 together, same, reboot

[chrisDupuis]

OK, the problem is here:

while (rx_fifo_len)
  {
    // rxbuf[buffer_index] = UART1.fifo.rw_byte; // read all bytes
    //rxbuf[buffer_index] = UART1.ahb_fifo.rw_byte; // read all bytes
    rxbuf[buffer_index] = READ_PERI_REG(UART_FIFO_AHB_REG(1));

    rx_fifo_len--;
    buffer_index++;
    // Serial.print(rxbuf[buffer_index],HEX);
    // Serial.print(" ");
    /*if(rxbuf[0] == 0x0f){                     // Start of SBUS(2) Frame
      buffer_index++;
    }
    else{                                       // Telemetry Slot?
    //digitalWrite(16,HIGH);
    buffer_index++;
    }*/
  }

OK Running with that and fix use of TIMER_1

[ericlangel]

Nice to hear.

What did u change? just READ_PERI_REG(UART_FIFO_AHB_REG(1)) ?

is it still working on esp32 (without S2)? And SBUS2 is working, too?

[chrisDupuis]

Here the code for ESP32 and ESP32_S2

/*
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/
#if defined(ESP32)
#include "SBUS_usart.h"
#include "esp32-hal.h"
#include "esp32-hal-uart.h"

// #include "freertos/FreeRTOS.h"
// #include "freertos/event_groups.h"
// #include "esp_task.h"
// #include "esp_task_wdt.h"
// #include "freertos/queue.h"
#include "driver/uart.h"
#include <soc/uart_reg.h>
#include <driver/timer.h>
#include <soc/uart_struct.h>
#include <soc/timer_group_struct.h>

#include <stdarg.h>
#include <stdlib.h>
#include <string.h>

#define SLOT_DATA_LENGTH 3
#define NUMBER_OF_FRAMES 4
#define NUMBER_OF_SLOT 32
#define NUMBER_OF_SLOT_IN_FRAME 8
#define SBUS_FRAME_SIZE 25

#if CONFIG_IDF_TARGET_ESP32
#define SBUS2_UART_RX_PIN (GPIO_NUM_25)
#define SBUS2_UART_TX_PIN (GPIO_NUM_26)
#elif CONFIG_IDF_TARGET_ESP32S2
#define SBUS2_UART_RX_PIN (16)
#define SBUS2_UART_TX_PIN (17)
#endif

#define UART_RXBUFSIZE 30

#define SLOT_TIME 660  // 660 ms
#define WAIT_TIME 2000 // 2000 ms

#define RX_BUF_SIZE 1024 // we dont need more space in buffer

bool DemoMode = false;

// 32 Slots for telemetrie Data
uint8_t Slot_ID[NUMBER_OF_SLOT] = {0x03, 0x83, 0x43, 0xC3, 0x23, 0xA3, 0x63, 0xE3,
                                   0x13, 0x93, 0x53, 0xD3, 0x33, 0xB3, 0x73, 0xF3,
                                   0x0B, 0x8B, 0x4B, 0xCB, 0x2B, 0xAB, 0x6B, 0xEB,
                                   0x1B, 0x9B, 0x5B, 0xDB, 0x3B, 0xBB, 0x7B, 0xFB};

char sbus_frame[25] = {0x0F, 0xA0, 0xA3, 0x20, 0x56, 0x2C, 0x08, 0x16, 0x50, 0x03, 0x10, 0x80, 0x00, 0x04, 0x20, 0x00, 0x01, 0x08, 0x07, 0xC8, 0x03, 0x10, 0x80, 0x02, 0x04};

// channels for connected servos at the SBUS
uint16_t channels[NUMBER_OF_CHANNELS];

static volatile uint8_t rxbuf[UART_RXBUFSIZE];
static volatile uint8_t sbusData[UART_RXBUFSIZE];
static volatile uint8_t telemetryData[256];
static volatile bool frame_ready = false;
static volatile bool telemetry_ready = false;
static volatile bool sbus_ready = false;
static volatile uint8_t gl_current_frame = 0;
static volatile uint16_t uart_lost_frame = 0;
static volatile uint8_t FER_count = 0;
static volatile uint8_t FER_buf[100];

static volatile uint8_t buffer_index = 0;

static volatile uint8_t tx_pin;
uart_port_t uart_num;

typedef enum
{
  EMPTY = 0,
  TRANSMITTING,
  AVAILABLE
} SLOT_DATA_STATUS;

typedef struct
{
  bool data_status;
  uint8_t data[SLOT_DATA_LENGTH];
} SLOT_RAW_DATA;

static volatile int8_t previousFrame = 0;
static volatile uint32_t frameCounter = 0;

static volatile uint8_t sequence_count = 0; // first sequence step delay will be filled in when the transmit sequence is enabled

static volatile bool transmit = false;

volatile SLOT_DATA_STATUS transmit_data_per_slot_status[NUMBER_OF_SLOT];
volatile uint8_t transmit_data_per_slot_data[NUMBER_OF_SLOT][SLOT_DATA_LENGTH];

void initialize_slot_status();
void enable_receiving();
void disable_receiving();
void start_transmit_sequencer(uint8_t frame_number);

void SBUS2_get_all_servo_data();

/*******************************************************************************
 * ESP32 is able to invert the RX and TX Lines itself, so we dont need an external inverter
 * Also the HardwareSerial Library has interup driven input/output buffers and we dont need
 * to implent this on our own.
 * I implement the receiver part as an extra task, to avoid looping in main loop.
 * The transmitter is also implemented as a task to be able to follow the requird timings.
 *
 */

uart_config_t uart_config = {
    .baud_rate = 100000,
    .data_bits = UART_DATA_8_BITS,
    .parity = UART_PARITY_EVEN,
    .stop_bits = UART_STOP_BITS_2,
    .flow_ctrl = UART_HW_FLOWCTRL_DISABLE};

timer_config_t timer_config = {
    .alarm_en = TIMER_ALARM_EN,         // Alarm Enable
    .counter_en = TIMER_PAUSE,          // If the counter is enabled it will start incrementing / decrementing immediately after calling timer_init()
    .intr_type = TIMER_INTR_LEVEL,      // Is interrupt is triggered on timer’s alarm (timer_intr_mode_t)
    .counter_dir = TIMER_COUNT_UP,      // Does counter increment or decrement (timer_count_dir_t)
    .auto_reload = TIMER_AUTORELOAD_EN, // If counter should auto_reload a specific initial value on the timer’s alarm, or continue incrementing or decrementing.
    .divider = 80                       // Divisor of the incoming 80 MHz (12.5nS) APB_CLK clock. E.g. 80 = 1uS per timer tick
};

/* ISR to transmit the frame */
static void IRAM_ATTR ISR_transmit_frame(void *arg);
static void IRAM_ATTR uart_intr_handle(void *arg);

//*****************************************************************************
//
void SBUS2_enable_simulation()
{
  log_i("[SBUS2] Demo Mode enabled");
  DemoMode = true;
}

void SBUS2_disable_simulation()
{
  log_i("[SBUS2] Demo Mode disabled");
  DemoMode = false;
}

void SBUS2_uart_setup()
{
  SBUS2_uart_setup(SBUS2_UART_RX_PIN, SBUS2_UART_TX_PIN, UART_NUM_1);
}

void SBUS2_uart_setup(int rx, int tx)
{
  SBUS2_uart_setup(rx, tx, UART_NUM_1);
}

void SBUS2_uart_setup(int rx, int tx, int uart)
{
  tx_pin = tx;
  uart_num = (uart_port_t)uart;
  ESP_ERROR_CHECK(uart_param_config(uart_num, &uart_config));
#if (ESP_ARDUINO_VERSION_MAJOR == 2)
  ESP_ERROR_CHECK(uart_set_line_inverse(uart_num, UART_SIGNAL_TXD_INV | UART_SIGNAL_RXD_INV)); // V2.0.0
#else
  ESP_ERROR_CHECK(uart_set_line_inverse(uart_num, UART_INVERSE_RXD | UART_INVERSE_TXD)); // V1.6.0
#endif
  ESP_ERROR_CHECK(uart_set_pin(uart_num, tx, rx, UART_PIN_NO_CHANGE, UART_PIN_NO_CHANGE));
  gpio_set_pull_mode((gpio_num_t)rx, GPIO_PULLDOWN_ONLY);
  gpio_pulldown_en((gpio_num_t)rx);
  ESP_ERROR_CHECK(uart_driver_install(uart_num, RX_BUF_SIZE, 0, 0, NULL, 0));
  ESP_ERROR_CHECK(uart_isr_free(uart_num));
  ESP_ERROR_CHECK(uart_isr_register(uart_num, uart_intr_handle, NULL, ESP_INTR_FLAG_IRAM, 0 /*handle_console*/));
  ESP_ERROR_CHECK(uart_enable_rx_intr(uart_num));

  // setup transmitter ISR
  timer_init(TIMER_GROUP_0, TIMER_1, &timer_config);
  timer_set_counter_value(TIMER_GROUP_0, TIMER_1, 0);
  timer_set_alarm_value(TIMER_GROUP_0, TIMER_1, SLOT_TIME);
  timer_enable_intr(TIMER_GROUP_0, TIMER_1);
  timer_isr_register(TIMER_GROUP_0, TIMER_1, &ISR_transmit_frame, NULL, 0, 0 /*&s_timer_handle*/);
  timer_set_alarm(TIMER_GROUP_0, TIMER_1, TIMER_ALARM_EN);

  uart_flush(uart_num);

  uart_intr_config_t uart_intr;
  uart_intr.intr_enable_mask = UART_RXFIFO_FULL_INT_ENA_M | UART_RXFIFO_TOUT_INT_ENA_M;
  uart_intr.rxfifo_full_thresh = 26;
  uart_intr.rx_timeout_thresh = 2;
  uart_intr.txfifo_empty_intr_thresh = 10;
  uart_intr_config(uart_num, &uart_intr);

  initialize_slot_status();

  enable_receiving();

  if (DemoMode)
  { // Nur wenn demo Mode
    uart_write_bytes(uart_num, sbus_frame, SBUS_FRAME_SIZE);
    sbus_frame[24] += 0x10;
  }
  else
  {
    pinMatrixOutDetach(tx_pin, false, true);
  }
}

void initialize_slot_status()
{
  for (uint8_t i = 0; i < NUMBER_OF_SLOT; i++)
  {
    transmit_data_per_slot_status[i] = EMPTY;
  }
}

void disable_receiving()
{
  sequence_count = 0;

  timer_set_alarm(TIMER_GROUP_0, TIMER_1, TIMER_ALARM_DIS);
  timer_pause(TIMER_GROUP_0, TIMER_1);

  timer_set_alarm_value(TIMER_GROUP_0, TIMER_1, WAIT_TIME); // RX Interrupt with delay of 700µs -> 700µs + 1300µs = 2ms
  timer_set_counter_value(TIMER_GROUP_0, TIMER_1, 0);
  timer_set_alarm(TIMER_GROUP_0, TIMER_1, TIMER_ALARM_EN);
  timer_start(TIMER_GROUP_0, TIMER_1);
}

void enable_receiving()
{
  // disable transmitter ISR
  /*timer_set_alarm(TIMER_GROUP_0,TIMER_1,TIMER_ALARM_DIS);
  timer_pause(TIMER_GROUP_0,TIMER_1);
  timer_set_counter_value(TIMER_GROUP_0,TIMER_1,0);*/

  timer_set_counter_value(TIMER_GROUP_0, TIMER_1, 0);
  timer_set_alarm_value(TIMER_GROUP_0, TIMER_1, 15000);
  timer_set_alarm(TIMER_GROUP_0, TIMER_1, TIMER_ALARM_EN);

  // flush input buffer first, to avoid getting old SBUS-Frames
  // uart_flush(uart_num);
  buffer_index = 0;
}

inline void IncreaseTimer(int8_t frameNumber)
{
  int8_t temp = (frameNumber - previousFrame) % NUMBER_OF_FRAMES;
  if (temp <= 0)
    temp += NUMBER_OF_FRAMES;
  if (temp > 1)
    uart_lost_frame++;
  frameCounter += temp;
  previousFrame = frameNumber;
}

static void IRAM_ATTR uart_intr_handle(void *arg)
{
  // digitalWrite(18,HIGH);
  // CHD pinMatrixOutDetach(tx_pin, false, true);
  uart_clear_intr_status(uart_num, UART_RXFIFO_FULL_INT_CLR | UART_RXFIFO_TOUT_INT_CLR);
  uint16_t rx_fifo_len, status;
  status = UART1.int_st.val;             // read UART interrupt Status
  rx_fifo_len = UART1.status.rxfifo_cnt; // read number of bytes in UART buffer
  /*Serial.print("Fifo len = ");
  Serial.println(rx_fifo_len);*/
  if (rx_fifo_len == 0)
  {
    return;
  }
  else if (rx_fifo_len == 25)
  {
  }
  else if (rx_fifo_len == 3)
  {
  }
  else
  {
    // digitalWrite(18,HIGH);
    /*Serial.print("Error! -> rx_fifo_len = ");
    Serial.print(rx_fifo_len);
    Serial.print(" Value = ");
    for(uint8_t i=0; i<=rx_fifo_len;i++){
    Serial.print(rxbuf[i], HEX);
    Serial.print(", ");
    }
    Serial.println(" [HEX]");*/
    uart_flush(uart_num);
    uart_clear_intr_status(uart_num, UART_RXFIFO_FULL_INT_CLR | UART_RXFIFO_TOUT_INT_CLR);
    log_i("[SBUS2] Wrong Frame length\l\n");
    return;
  }
  // digitalWrite(18,HIGH);

  while (rx_fifo_len)
  {
#if CONFIG_IDF_TARGET_ESP32
    rxbuf[buffer_index] = UART1.fifo.rw_byte; // read all bytes
#elif CONFIG_IDF_TARGET_ESP32S2
    rxbuf[buffer_index] = READ_PERI_REG(UART_FIFO_AHB_REG(1));
#endif
    rx_fifo_len--;
    buffer_index++;
    // Serial.print(rxbuf[buffer_index],HEX);
    // Serial.print(" ");
    /*if(rxbuf[0] == 0x0f){                     // Start of SBUS(2) Frame
      buffer_index++;
    }
    else{                                       // Telemetry Slot?
    //digitalWrite(16,HIGH);
    buffer_index++;
    }*/
  }
  if ((buffer_index == SBUS_FRAME_SIZE) && (rxbuf[0] == 0x0f)) // SBUS Frame
  {
    // digitalWrite(18,HIGH);
    telemetry_ready = false;
    sbus_ready = false;
    frame_ready = true;
    for (uint8_t i = 0; i < UART_RXBUFSIZE; i++)
    {
      sbusData[i] = rxbuf[i];
    }
    disable_receiving();
    IncreaseTimer((rxbuf[24] & 0x30) >> 4);
    buffer_index = 0;
    // Serial.println();
    if ((rxbuf[24] & 0x0f) == 0x04)
    { // Valid SBUS2 Frame
      // digitalWrite(18,HIGH);
      telemetry_ready = true;
      sbus_ready = true;
      SBUS2_get_all_servo_data();
      start_transmit_sequencer(((rxbuf[24] & 0x30) >> 4)); // frame number needed to select correct telemetry slot
    }
    else if ((rxbuf[24] & 0x0f) == 0x00)
    { // Just SBUS Frame (without Telemetry)
      telemetry_ready = false;
      sbus_ready = true;
      SBUS2_get_all_servo_data();
    }
    else
    { // Something else -> Error
      telemetry_ready = false;
      sbus_ready = false;
      uart_flush(uart_num);
      uart_clear_intr_status(uart_num, UART_RXFIFO_FULL_INT_CLR | UART_RXFIFO_TOUT_INT_CLR);
      log_i("[SBUS2]Invalid Frame End Byte");
    }
    // pinMatrixOutDetach(tx_pin,false,true);
  }
  else if (buffer_index == SBUS_FRAME_SIZE)
  {
    uart_flush(uart_num);
    uart_clear_intr_status(uart_num, UART_RXFIFO_FULL_INT_CLR | UART_RXFIFO_TOUT_INT_CLR);
    log_i("[SBUS2] Invalid Frame Start Byte");
  }
  else if ((buffer_index == SLOT_DATA_LENGTH) && ((((rxbuf[0] & 0x0f) == 0x03) || (rxbuf[0] & 0x0f) == 0x0B))) // Telemetry Slot
  {
    // digitalWrite(18,HIGH);
    uint8_t temp = rxbuf[0];
    telemetryData[temp] = rxbuf[0];
    telemetryData[temp + 1] = rxbuf[1];
    telemetryData[temp + 2] = rxbuf[2];
    buffer_index = 0;
    // pinMatrixOutDetach(tx_pin,false,true);
    // digitalWrite(18,LOW);
  }
  else if (buffer_index == SLOT_DATA_LENGTH)
  { // Something went wrong
    uart_flush(uart_num);
    uart_clear_intr_status(uart_num, UART_RXFIFO_FULL_INT_CLR | UART_RXFIFO_TOUT_INT_CLR);
    log_i("[SBUS2] Invalid Slot ID");
  }
  //}
  // digitalWrite(18,LOW);
  // after reading bytes from buffer clear UART interrupt status
  // uart_flush(uart_num);
  uart_clear_intr_status(uart_num, UART_RXFIFO_FULL_INT_CLR | UART_RXFIFO_TOUT_INT_CLR);
}

/****************************************************************
 * transmit_frame
 *
 * Implemented as an ISR to fit the strict timing requirements
 * Slot 1 has to be transmitted 2ms after receiving the SBUS2 Frame
 * Slot 2-8 has to be transmitted every 660 mirco seconds
 * Each Slot needs about 320 mircoseconds to be transmitted via uart
 * The delay between the Slots must not exceed 400 mirco seconds
 *
 ****************************************************************/

static void IRAM_ATTR ISR_transmit_frame(void *arg)
{
#if CONFIG_IDF_TARGET_ESP32
  TIMERG0.int_clr_timers.t1 = 1;
  TIMERG0.hw_timer[1].config.alarm_en = 1;
#elif CONFIG_IDF_TARGET_ESP32S2
  timer_group_clr_intr_status_in_isr(TIMER_GROUP_0, TIMER_1);
  TIMERG0.hw_timer[0].config.tx_alarm_en = 1;
#endif
  digitalWrite(18, HIGH);
  pinMatrixOutDetach(tx_pin, false, true);
  if (sequence_count < 8) // transmit slots
  {
    uint8_t actual_slot = (sequence_count) + (gl_current_frame * NUMBER_OF_SLOT_IN_FRAME);
    // if data available in slot then send it
    if (transmit_data_per_slot_status[actual_slot] == AVAILABLE)
    {
      // digitalWrite(18,HIGH);
      pinMatrixOutAttach(tx_pin, U1TXD_OUT_IDX, false, false);
      char buffer[SLOT_DATA_LENGTH];
      memcpy(buffer, (const void *)transmit_data_per_slot_data[actual_slot], SLOT_DATA_LENGTH);
      transmit_data_per_slot_status[actual_slot] = TRANSMITTING;
      // send the whole slot
      uart_write_bytes(uart_num, buffer, SLOT_DATA_LENGTH);
      transmit_data_per_slot_status[actual_slot] = EMPTY;
      // digitalWrite(18,LOW);
    }
    if (sequence_count == 7)
    {
      timer_set_counter_value(TIMER_GROUP_0, TIMER_1, 0);
      timer_set_alarm_value(TIMER_GROUP_0, TIMER_1, 5150);
      // timer_set_counter_value(TIMER_GROUP_0, TIMER_1, 0);
      timer_set_alarm(TIMER_GROUP_0, TIMER_1, TIMER_ALARM_EN);
    }
    else
    {
      timer_set_counter_value(TIMER_GROUP_0, TIMER_1, 0);
      timer_set_alarm_value(TIMER_GROUP_0, TIMER_1, SLOT_TIME);
      // timer_set_counter_value(TIMER_GROUP_0, TIMER_1, 0);
      timer_set_alarm(TIMER_GROUP_0, TIMER_1, TIMER_ALARM_EN);
    }
  }
  /*else if(sequence_count = 8){
  timer_set_counter_value(TIMER_GROUP_0, TIMER_1, 0);
    timer_set_alarm_value(TIMER_GROUP_0, TIMER_1, 4500);
  //timer_set_counter_value(TIMER_GROUP_0, TIMER_1, 0);
    timer_set_alarm(TIMER_GROUP_0,TIMER_1,TIMER_ALARM_EN);
  }*/

  else
  {
    // digitalWrite(18,HIGH);   // dummy for sending SBUS2 Frame
    if (DemoMode)
    {
      pinMatrixOutAttach(tx_pin, U1TXD_OUT_IDX, false, false);
      uart_write_bytes(uart_num, sbus_frame, SBUS_FRAME_SIZE);
      sbus_frame[24] += 0x10;
      if (sbus_frame[24] > 0x34)
      {
        sbus_frame[24] = 0x04;
      }
    }
    else
    {
      // pinMatrixOutDetach(tx_pin,false,true);
    }

    buffer_index = 0;
    transmit = false;
    // telemetry_ready = false;
    sequence_count = 0;

    enable_receiving();
  }
  // digitalWrite(18,LOW);
  sequence_count++;
}

void start_transmit_sequencer(uint8_t frame_number)
{
  gl_current_frame = frame_number;
  // we dont need more frames to be received, lets handle this one first
  disable_receiving();
}

void SBUS2_transmit_telemetry_data(uint8_t slot, uint8_t data[SLOT_DATA_LENGTH])
{
  if (transmit_data_per_slot_status[slot] != TRANSMITTING)
  {

    transmit_data_per_slot_data[slot][0] = Slot_ID[slot];
    transmit_data_per_slot_data[slot][1] = data[1];
    transmit_data_per_slot_data[slot][2] = data[2];

    transmit_data_per_slot_status[slot] = AVAILABLE;
  }
}

void SBUS2_get_all_servo_data()
{
  channels[0] = ((sbusData[1] | sbusData[2] << 8) & 0x07FF);
  channels[1] = ((sbusData[2] >> 3 | sbusData[3] << 5) & 0x07FF);
  channels[2] = ((sbusData[3] >> 6 | sbusData[4] << 2 | sbusData[5] << 10) & 0x07FF);
  channels[3] = ((sbusData[5] >> 1 | sbusData[6] << 7) & 0x07FF);
  channels[4] = ((sbusData[6] >> 4 | sbusData[7] << 4) & 0x07FF);
  channels[5] = ((sbusData[7] >> 7 | sbusData[8] << 1 | sbusData[9] << 9) & 0x07FF);
  channels[6] = ((sbusData[9] >> 2 | sbusData[10] << 6) & 0x07FF);
  channels[7] = ((sbusData[10] >> 5 | sbusData[11] << 3) & 0x07FF);
  channels[8] = ((sbusData[12] | sbusData[13] << 8) & 0x07FF);
  channels[9] = ((sbusData[13] >> 3 | sbusData[14] << 5) & 0x07FF);
  channels[10] = ((sbusData[14] >> 6 | sbusData[15] << 2 | sbusData[16] << 10) & 0x07FF);
  channels[11] = ((sbusData[16] >> 1 | sbusData[17] << 7) & 0x07FF);
  channels[12] = ((sbusData[17] >> 4 | sbusData[18] << 4) & 0x07FF);
  channels[13] = ((sbusData[18] >> 7 | sbusData[19] << 1 | sbusData[20] << 9) & 0x07FF);
  channels[14] = ((sbusData[20] >> 2 | sbusData[21] << 6) & 0x07FF);
  channels[15] = ((sbusData[21] >> 5 | sbusData[22] << 3) & 0x07FF);

  // DigiChannel 1
  if (sbusData[23] & (1 << 0))
  {
    channels[16] = 1;
  }
  else
  {
    channels[16] = 0;
  }
  // DigiChannel 2
  if (sbusData[23] & (1 << 1))
  {
    channels[17] = 1;
  }
  else
  {
    channels[17] = 0;
  }
  if (sbusData[23] & 0x04)
  {
    FER_buf[FER_count] = 1;
    FER_count++;
    if (FER_count > 99)
    {
      FER_count = 0;
    }
  }
  else
  {
    FER_buf[FER_count] = 0;
    FER_count++;
    if (FER_count > 99)
    {
      FER_count = 0;
    }
  }
}

void SBUS2_get_status(uint16_t *uart_dropped_frame, bool *transmision_dropt_frame, bool *failsave)
{
  if (frameCounter < 60)
  {
    uart_lost_frame = 0;
  }
  *uart_dropped_frame = uart_lost_frame;
  uart_lost_frame = 0;
  *transmision_dropt_frame = sbusData[23] & 0x04 ? true : false;
  *failsave = sbusData[23] & 0x08 ? true : false;
}

int16_t SBUS2_get_servo_data(uint8_t channel)
{
  if (channel < NUMBER_OF_CHANNELS)
  {
    return channels[channel];
  }
  else
  {
    return -1;
  }
}

bool SBUS_Ready()
{
  if (sbus_ready) // Checking sbus_ready Flag
  {
    sbus_ready = false;
    return true;
  }
  else
  {
    return false;
  }
}

bool SBUS2_Ready()
{
  // Serial.println("test");
  if (telemetry_ready)
  {
    telemetry_ready = false;
    // digitalWrite(18,LOW);
    return true;
  }
  else
  {
    return false;
  }
}

bool SBUS_Ready(bool reset)
{
  if (sbus_ready) // Checking sbus_ready Flag
  {
    if (reset)
    {
      sbus_ready = false;
    }
    return true;
  }
  else
  {
    return false;
  }
}

bool SBUS2_Ready(bool reset)
{
  if (telemetry_ready)
  {
    if (reset)
    {
      telemetry_ready = false;
    }
    return true;
  }
  else
  {
    return false;
  }
}

uint8_t SBUS_get_FER()
{
  uint8_t fer = 0;
  for (uint8_t i = 0; i < 100; i++)
  {
    if (FER_buf[i] == 1)
    {
      fer++;
    }
  }
  return fer;
}

uint8_t SBUS_get_RSSI()
{
  uint8_t rssi = SBUS_get_FER();
  rssi = 100 - rssi;
  return rssi;
}

void SBUS2_print_Raw()
{
  for (uint16_t i = 0; i < 256; i++)
  {
    Serial.print(i, HEX);
    Serial.print(" ");
  }
  Serial.println();
  for (uint16_t i = 0; i < 256; i++)
  {
    Serial.print(telemetryData[i], HEX);
    Serial.print(" ");
  }
  Serial.println();
}

bool SBUS2_get_Slot(uint8_t slot, uint8_t *lowbyte, uint8_t *highbyte)
{
  uint8_t slotid = Slot_ID[slot];
  if (telemetryData[slotid] == slotid)
  {
    // Sensordaten vorhanden
    *lowbyte = telemetryData[slotid + 1];
    *highbyte = telemetryData[slotid + 2];
    telemetryData[slotid] = 0;
    telemetryData[slotid + 1] = 0;
    telemetryData[slotid + 2] = 0;
    return true;
  }
  else
  {
    // Keine Sensordaten vorhanden
    *lowbyte = 0;
    *highbyte = 0;
    return false;
  }
}

void SBUS_disable()
{
  uart_disable_rx_intr(uart_num);
  timer_set_alarm(TIMER_GROUP_0, TIMER_1, TIMER_ALARM_DIS);
}

void SBUS_enable()
{
  uart_enable_rx_intr(uart_num);
  initialize_slot_status();
  enable_receiving();
}

void SBUS2_disable()
{
  SBUS_disable();
}

void SBUS2_enable()
{
  SBUS_enable();
}
#endif // ESP32

[chrisDupuis]

Fixed

[ericlangel]

OK, i have some questions:

u used PIN16/17 on the S2 -> why? are 25/26 not working?

and u changed:

#if CONFIG_IDF_TARGET_ESP32
  TIMERG0.int_clr_timers.t1 = 1;
  TIMERG0.hw_timer[1].config.alarm_en = 1;
#elif CONFIG_IDF_TARGET_ESP32S2
  timer_group_clr_intr_status_in_isr(TIMER_GROUP_0, TIMER_1);
  TIMERG0.hw_timer[0].config.tx_alarm_en = 1;
#endif

TIMERG0.hw_timer[0].config.tx_alarm_en = 1; -> seems wrong to me should it beTIMERG0.hw_timer[1].config.tx_alarm_en = 1;?

[chrisDupuis]

I use 25/26 because I use an ESP32 S2 Mini Lolin, and no 25/26 pin. and You re right, it s a mistake, it must be: TIMERG0.hw_timer[1].config.tx_alarm_en = 1;