- Muchas notas - Fran Acién

The tests of the COMM PCB are:

1. LoRa Communication
- 1.1. Transmit
- 1.2. Receive
1. CAN communication
- 2.1 Check mode ✅
- 2.2 Check enable ✅
- 2.3 Transmit ✅
- 2.4. Receive ✅
1. Why the JTAG interface is not working?

1

I used this source to transmit and receive. In the other end I had the arduino with lora, that is using another library. And the result was that they were not able to communicate to each other.

2.1 2.2

I checked the enable in the multimeter, and I forgot that is necessary to enable the transceiver by code. It is placed on the GPIO16.

2.4

I am able to receive packets using the library from esp, but the serial is stucked and is all the time reading the same message. The code is next one:

/* ESP32 TWAI receive example.
  Receive messages and sends them over serial.

  Connect a CAN bus transceiver to the RX/TX pins.
  For example: SN65HVD230

  TWAI_MODE_LISTEN_ONLY is used so that the TWAI controller will not influence the bus.

  The API gives other possible speeds and alerts:
  https://docs.espressif.com/projects/esp-idf/en/latest/esp32/api-reference/peripherals/twai.html

  Example output from a can bus message:
  -> Message received
  -> Message is in Standard Format
  -> ID: 604
  -> Byte: 0 = 00, 1 = 0f, 2 = 13, 3 = 02, 4 = 00, 5 = 00, 6 = 08, 7 = 00

  Example output with alerts:
  -> Alert: A (Bit, Stuff, CRC, Form, ACK) error has occurred on the bus.
  -> Bus error count: 171
  -> Alert: The RX queue is full causing a received frame to be lost.
  -> RX buffered: 4  RX missed: 46 RX overrun 0

  created 05-11-2022 by Stephan Martin (designer2k2)
*/

#include "driver/twai.h"

// Pins used to connect to CAN bus transceiver:
#define RX_PIN 15
#define TX_PIN 14

#define CAN_EN_PIN 16

// Intervall:
#define POLLING_RATE_MS 1000

static bool driver_installed = false;

void setup() {
  // Start Serial:
  Serial.begin(115200);

  pinMode(CAN_EN_PIN, OUTPUT);
  digitalWrite(CAN_EN_PIN, HIGH);

  // Initialize configuration structures using macro initializers
  twai_general_config_t g_config = TWAI_GENERAL_CONFIG_DEFAULT((gpio_num_t)TX_PIN, (gpio_num_t)RX_PIN, TWAI_MODE_LISTEN_ONLY);
  twai_timing_config_t t_config = TWAI_TIMING_CONFIG_500KBITS();  //Look in the api-reference for other speed sets.
  twai_filter_config_t f_config = TWAI_FILTER_CONFIG_ACCEPT_ALL();

  // Install TWAI driver
  if (twai_driver_install(&g_config, &t_config, &f_config) == ESP_OK) {
    Serial.println("Driver installed");
  } else {
    Serial.println("Failed to install driver");
    return;
  }

  // Start TWAI driver
  if (twai_start() == ESP_OK) {
    Serial.println("Driver started");
  } else {
    Serial.println("Failed to start driver");
    return;
  }

  // Reconfigure alerts to detect frame receive, Bus-Off error and RX queue full states
  uint32_t alerts_to_enable = TWAI_ALERT_RX_DATA | TWAI_ALERT_ERR_PASS | TWAI_ALERT_BUS_ERROR | TWAI_ALERT_RX_QUEUE_FULL;
  if (twai_reconfigure_alerts(alerts_to_enable, NULL) == ESP_OK) {
    Serial.println("CAN Alerts reconfigured");
  } else {
    Serial.println("Failed to reconfigure alerts");
    return;
  }

  // TWAI driver is now successfully installed and started
  driver_installed = true;
}

static void handle_rx_message(twai_message_t& message) {
  // Process received message
  if (message.extd) {
    Serial.println("Message is in Extended Format");
  } else {
    Serial.println("Message is in Standard Format");
  }
  Serial.printf("ID: %x\nByte:", message.identifier);
  if (!(message.rtr)) {
    for (int i = 0; i < message.data_length_code; i++) {
      Serial.printf(" %d = %02x,", i, message.data[i]);
    }
    Serial.println("");
  }
}

void loop() {
  if (!driver_installed) {
    // Driver not installed
    delay(1000);
    return;
  }
  // Check if alert happened
  uint32_t alerts_triggered;
  twai_read_alerts(&alerts_triggered, pdMS_TO_TICKS(POLLING_RATE_MS));
  twai_status_info_t twaistatus;
  twai_get_status_info(&twaistatus);

  // Handle alerts
  if (alerts_triggered & TWAI_ALERT_ERR_PASS) {
    Serial.println("Alert: TWAI controller has become error passive.");
  }
  if (alerts_triggered & TWAI_ALERT_BUS_ERROR) {
    Serial.println("Alert: A (Bit, Stuff, CRC, Form, ACK) error has occurred on the bus.");
    Serial.printf("Bus error count: %d\n", twaistatus.bus_error_count);
  }
  if (alerts_triggered & TWAI_ALERT_RX_QUEUE_FULL) {
    Serial.println("Alert: The RX queue is full causing a received frame to be lost.");
    Serial.printf("RX buffered: %d\t", twaistatus.msgs_to_rx);
    Serial.printf("RX missed: %d\t", twaistatus.rx_missed_count);
    Serial.printf("RX overrun %d\n", twaistatus.rx_overrun_count);
  }

  // Check if message is received
  if (alerts_triggered & TWAI_ALERT_RX_DATA) {
    // One or more messages received. Handle all.
    twai_message_t message;
    while (twai_receive(&message, 0) == ESP_OK) {
      handle_rx_message(message);
    }
  }
}

The conclusion is that, there is no CAN library that works correctly on the ESP32S3, or at least I have not found it.

The solutions are:

Make the official driver to work on ESP32S3
Adapt the library I know is working to ESP32S3
Modify the PCB to use the previous ESP, and use the libraries I know are working

I tried to send messages with the official driver on the esp32 dev kit, and it is stucked reading a message from the queue, it is not updated correctly. I tried to use esp32_can without much success.

ESP CAN TWAI Self test

The steps were to upload the twai self test with the transceiver connecter. The output is that is working. I needed to short the enable pin directly to VCC

CAN test now is working

After doing the short in the enable pin.… it works. Why? Not sure. But I am able to receive.

CAN TRANSMISSION WORKING

I removed the wire from CAN_EN, and is working. It is strange, but somehow now is working.

/* ESP32 TWAI receive example.
  Receive messages and sends them over serial.

  Connect a CAN bus transceiver to the RX/TX pins.
  For example: SN65HVD230

  TWAI_MODE_LISTEN_ONLY is used so that the TWAI controller will not influence the bus.

  The API gives other possible speeds and alerts:
  https://docs.espressif.com/projects/esp-idf/en/latest/esp32/api-reference/peripherals/twai.html

  Example output from a can bus message:
  -> Message received
  -> Message is in Standard Format
  -> ID: 604
  -> Byte: 0 = 00, 1 = 0f, 2 = 13, 3 = 02, 4 = 00, 5 = 00, 6 = 08, 7 = 00

  Example output with alerts:
  -> Alert: A (Bit, Stuff, CRC, Form, ACK) error has occurred on the bus.
  -> Bus error count: 171
  -> Alert: The RX queue is full causing a received frame to be lost.
  -> RX buffered: 4  RX missed: 46 RX overrun 0

  created 05-11-2022 by Stephan Martin (designer2k2)
*/

#include "driver/twai.h"

// Pins used to connect to CAN bus transceiver:
#define RX_PIN 15
#define TX_PIN 14

#define CAN_EN_PIN 16

// Intervall:
#define POLLING_RATE_MS 1000

static bool driver_installed = false;

void setup() {
  // Start Serial:
  Serial.begin(115200);

  pinMode(CAN_EN_PIN, OUTPUT);
  digitalWrite(CAN_EN_PIN, HIGH);

  // Initialize configuration structures using macro initializers
  twai_general_config_t g_config = TWAI_GENERAL_CONFIG_DEFAULT((gpio_num_t)TX_PIN, (gpio_num_t)RX_PIN, TWAI_MODE_NORMAL);
  twai_timing_config_t t_config = TWAI_TIMING_CONFIG_500KBITS();  //Look in the api-reference for other speed sets.
  twai_filter_config_t f_config = TWAI_FILTER_CONFIG_ACCEPT_ALL();

  // Install TWAI driver
  if (twai_driver_install(&g_config, &t_config, &f_config) == ESP_OK) {
    Serial.println("Driver installed");
  } else {
    Serial.println("Failed to install driver");
    return;
  }

  // Start TWAI driver
  if (twai_start() == ESP_OK) {
    Serial.println("Driver started");
  } else {
    Serial.println("Failed to start driver");
    return;
  }

  // Reconfigure alerts to detect frame receive, Bus-Off error and RX queue full states
  uint32_t alerts_to_enable = TWAI_ALERT_RX_DATA | TWAI_ALERT_ERR_PASS | TWAI_ALERT_BUS_ERROR | TWAI_ALERT_RX_QUEUE_FULL;
  if (twai_reconfigure_alerts(alerts_to_enable, NULL) == ESP_OK) {
    Serial.println("CAN Alerts reconfigured");
  } else {
    Serial.println("Failed to reconfigure alerts");
    return;
  }

  // TWAI driver is now successfully installed and started
  driver_installed = true;
}

static void handle_rx_message(twai_message_t& message) {
  // Process received message
  if (message.extd) {
    Serial.println("Message is in Extended Format");
  } else {
    Serial.println("Message is in Standard Format");
  }
  Serial.printf("ID: %x\nByte:", message.identifier);
  if (!(message.rtr)) {
    for (int i = 0; i < message.data_length_code; i++) {
      Serial.printf(" %d = %02x,", i, message.data[i]);
    }
    Serial.println("");
  }
}


void loop() {
  if (!driver_installed) {
    // Driver not installed
    delay(1000);
    return;
  }
  // Check if alert happened
  uint32_t alerts_triggered;
  twai_read_alerts(&alerts_triggered, pdMS_TO_TICKS(POLLING_RATE_MS));
  twai_status_info_t twaistatus;
  twai_get_status_info(&twaistatus);

  // Handle alerts
  if (alerts_triggered & TWAI_ALERT_ERR_PASS) {
    Serial.println("Alert: TWAI controller has become error passive.");
  }
  if (alerts_triggered & TWAI_ALERT_BUS_ERROR) {
    Serial.println("Alert: A (Bit, Stuff, CRC, Form, ACK) error has occurred on the bus.");
    Serial.printf("Bus error count: %d\n", twaistatus.bus_error_count);
  }
  if (alerts_triggered & TWAI_ALERT_RX_QUEUE_FULL) {
    Serial.println("Alert: The RX queue is full causing a received frame to be lost.");
    Serial.printf("RX buffered: %d\t", twaistatus.msgs_to_rx);
    Serial.printf("RX missed: %d\t", twaistatus.rx_missed_count);
    Serial.printf("RX overrun %d\n", twaistatus.rx_overrun_count);
  }

  // Check if message is received
  if (alerts_triggered & TWAI_ALERT_RX_DATA) {
    // One or more messages received. Handle all.
    twai_message_t message;
    while (twai_receive(&message, 0) == ESP_OK) {
      handle_rx_message(message);
    }
  }
}

/*
void loop(){
  if (!driver_installed) {
    // Driver not installed
    delay(1000);
    return;
  }

  //Configure message to transmit
  twai_message_t message;
  message.identifier = 0xAAAA;
  message.extd = 1;
  message.data_length_code = 4;
  for (int i = 0; i < 4; i++) {
      message.data[i] = 0;
  }

  //Queue message for transmission
  if (twai_transmit(&message, pdMS_TO_TICKS(1000)) == ESP_OK) {
      printf("Message queued for transmission\n");
  } else {
      printf("Failed to queue message for transmission\n");
  }

  delay(2000);
}
*/

Uploading code tests

Test 1

Source: https://docs.espressif.com/projects/esp-idf/en/stable/esp32/get-started/linux-macos-setup.html

Connected with the ESP-Prog with both interfaces, the jtag and the program interface.

Then I did:

$ sudo apt-get install git wget flex bison gperf python3 python3-venv cmake ninja-build ccache libffi-dev libss
l-dev dfu-util libusb-1.0-0\n
$ cd esp-idf-v5.0.1
$ ./install.sh esp32s3
$ chmod 755 export.sh
$ . ./export.sh
$ cd examples/get-started/hello_world
$ idf.py set-target esp32s3\n
$ idf.py build\n
$ idf.py -p /dev/ttyUSB1 flash
$ screen /dev/ttyUSB1 115200

While flashing it is necessary to press the boot button.

Restarting in 7 seconds...
Restarting in 6 seconds...
Restarting in 5 seconds...
Restarting in 4 seconds...
Restarting in 3 seconds...
Restarting in 2 seconds...
Restarting in 1 seconds...
Restarting in 0 seconds...
Restarting now.
ESP-ROM:esp32s3-20210327
Build:Mar 27 2021
rst:0x3 (RTC_SW_SYS_RST),boot:0x8 (SPI_FAST_FLASH_BOOT)
Saved PC:0x40375625
SPIWP:0xee
mode:DIO, clock div:1
load:0x3fce3810,len:0x164c
load:0x403c9700,len:0xbe0
load:0x403cc700,len:0x2ef8
entry 0x403c9900
I (29) boot: ESP-IDF v5.0.1-dirty 2nd stage bootloader
I (29) boot: compile time 13:24:59
I (29) boot: chip revision: v0.1
I (32) boot.esp32s3: Boot SPI Speed : 80MHz
I (36) boot.esp32s3: SPI Mode       : DIO
I (41) boot.esp32s3: SPI Flash Size : 2MB
I (46) boot: Enabling RNG early entropy source...
I (51) boot: Partition Table:
I (55) boot: ## Label            Usage          Type ST Offset   Length
I (62) boot:  0 nvs              WiFi data        01 02 00009000 00006000
I (70) boot:  1 phy_init         RF data          01 01 0000f000 00001000
I (77) boot:  2 factory          factory app      00 00 00010000 00100000
I (85) boot: End of partition table
I (89) esp_image: segment 0: paddr=00010020 vaddr=3c020020 size=08c84h ( 35972) map
I (104) esp_image: segment 1: paddr=00018cac vaddr=3fc91000 size=02318h (  8984) load
I (107) esp_image: segment 2: paddr=0001afcc vaddr=40374000 size=0504ch ( 20556) load
I (119) esp_image: segment 3: paddr=00020020 vaddr=42000020 size=195f4h (103924) map
I (141) esp_image: segment 4: paddr=0003961c vaddr=4037904c size=07f1ch ( 32540) load
I (154) boot: Loaded app from partition at offset 0x10000
I (154) boot: Disabling RNG early entropy source...
I (165) cpu_start: Pro cpu up.
I (166) cpu_start: Starting app cpu, entry point is 0x40375168
I (0) cpu_start: App cpu up.
I (180) cpu_start: Pro cpu start user code
I (180) cpu_start: cpu freq: 160000000 Hz
I (180) cpu_start: Application information:
I (183) cpu_start: Project name:     hello_world
I (188) cpu_start: App version:      v5.0.1-dirty
I (194) cpu_start: Compile time:     May 25 2023 13:24:52
I (200) cpu_start: ELF file SHA256:  0e14337c73093a5d...
I (206) cpu_start: ESP-IDF:          v5.0.1-dirty
I (211) cpu_start: Min chip rev:     v0.0
I (216) cpu_start: Max chip rev:     v0.99
I (221) cpu_start: Chip rev:         v0.1
I (226) heap_init: Initializing. RAM available for dynamic allocation:
I (233) heap_init: At 3FC93D38 len 000559D8 (342 KiB): D/IRAM
I (239) heap_init: At 3FCE9710 len 00005724 (21 KiB): STACK/DRAM
I (246) heap_init: At 3FCF0000 len 00008000 (32 KiB): DRAM
I (252) heap_init: At 600FE010 len 00001FF0 (7 KiB): RTCRAM
I (259) spi_flash: detected chip: gd
I (263) spi_flash: flash io: dio
W (267) spi_flash: Detected size(16384k) larger than the size in the binary image header(2048k). Using the size in the binary image header.
I (280) cpu_start: Starting scheduler on PRO CPU.
I (0) cpu_start: Starting scheduler on APP CPU.
Hello world!
This is esp32s3 chip with 2 CPU core(s), WiFi/BLE, silicon revision v0.1, 2MB external flash
Minimum free heap size: 391944 bytes
Restarting in 10 seconds...
Restarting in 9 seconds...
Restarting in 8 seconds...
Restarting in 7 seconds...
Restarting in 6 seconds...
Restarting in 5 seconds...
Restarting in 4 seconds...
Restarting in 3 seconds...

Test 2 - Upload code from arduino

The board in arduino ide is ESP32S3. Connect the 2 cables to the esp-prog. While uploading is necessary to press boot button.

A sample code is:

// the setup function runs once when you press reset or power the board
void setup() {
  // initialize digital pin LED_BUILTIN as an output.
  pinMode(36, OUTPUT);
  Serial.begin(9600);
}

// the loop function runs over and over again forever
void loop() {
  Serial.println("asdf");
  digitalWrite(36, HIGH);  // turn the LED on (HIGH is the voltage level)
  delay(1000);                      // wait for a second
  digitalWrite(36, LOW);   // turn the LED off by making the voltage LOW
  delay(1000);                      // wait for a second
}

Test 3 - Upload code from vscode platform io

Same setup

[env:esp32-s3-devkitc-1]
platform = espressif32
board = esp32-s3-devkitc-1
board_build.mcu = esp32s3
framework = arduino
debug_tool = esp-prog

Using the same code as arduino. Remember to press boot when uploading code.

Test 4 - Debugger

By default the JTAG interface is disabled, that is why is necessary to change something in the software.

https://docs.espressif.com/projects/esp-idf/en/latest/esp32/api-guides/jtag-debugging/tips-and-quirks.html#jtag-and-esp32-wroom-32-at-firmware-compatibility-issue

I have not been able to fix the debugger. It seems that is not detecting it -.-

EDIT: With the code that comes it is disable the jtag, but as soon as you program it will change.

Test Lora communication

It works. The setup is 2 pcbs sending messages.

KNOW ERRORS V0.1

The JTAG is not working, the debugger is not working. I am able to upload code but with the serial interface.
The mode is set to low power mode, it would be appreciated to put a solderbridge to select the mode
The transceiver is controlled by a pin. It would be nice to put a solderbridge to change the behaviour in testing.
The reset button sometimes is working and others not. When you press it, it freezes the board. Only when using arduino ide, then on platform io it works perfectly.
CAN_EN needs to be connected to VCC with a wire, otherwise is doing strange things.
The through hole pins are very narrow, it is not good for desoldering.
If you break the solderbridge SB1, then you need to push the prog button of the ESP-Prog while programming it.