Repetitive un-commanded CAN messages and Init sequence issue

[lolachampcar]

First ever issue report so please forgive me if I am not following proper procedure.

CANIPULATOR board, Arduino IDE, ESP32C6 Dev Module board choice

I am testing dual TWI (CAN) functionality by mirroring one bus to the other. I've found that changing the input CAN message ID causes the code to generate un-commanded CAN messages. Please see the attached screenshots

This is using an ID of 0x007 23 frames sent and 46 frames captured (the 23 sent to CAN0 and the 23 echoed back on CAN1)

Simply change the transmit id from 0x007 to 0x008 and this happens (8 sent and 66663 received)

I've tried to limit the code to the least elements necessary to limit possible causes.

#define CAN0_SHUTDOWN 3
#define CAN0_STANDBY 0

#define CAN1_SHUTDOWN 2
#define CAN1_STANDBY 1

void setup() {
Serial.begin(115200);

FastLED.addLeds<LED_TYPE, LED_PIN, COLOR_ORDER>(leds, NUM_LEDS);
FastLED.setBrightness(50);  // Start with low brightness

// setup CAN0 pins
pinMode(CAN0_SHUTDOWN, OUTPUT);
pinMode(CAN0_STANDBY, OUTPUT);
// enable CAN0 transceiver
digitalWrite(CAN0_SHUTDOWN, LOW);
digitalWrite(CAN0_STANDBY, LOW);

// setup CAN1 pins
pinMode(CAN1_SHUTDOWN, OUTPUT);
pinMode(CAN1_STANDBY, OUTPUT);
//enable CAN1 transceiver
digitalWrite(CAN1_SHUTDOWN, LOW);
digitalWrite(CAN1_STANDBY, LOW);

// setup CAN pins and speed

CAN1.setCANPins(GPIO_NUM_18, GPIO_NUM_19);
CAN1.begin(500000);
CAN1.watchFor();
CAN0.setCANPins(GPIO_NUM_16, GPIO_NUM_17);
CAN0.begin(500000);
CAN0.watchFor();
// CAN0.debuggingMode = true;
// CAN1.debuggingMode = true;

fill_solid(leds, NUM_LEDS, CRGB::Green);
FastLED.show();
delay(1000);

// Turn all LEDs off
fill_solid(leds, NUM_LEDS, CRGB::Black);
FastLED.show();
Serial.println("Exiting Setup");

}

auto lastCan0Frame = 0;
auto lastCan1Frame = 0;

void loop() {
CAN_FRAME frame0;

if (CAN0.available() && CAN0.read(frame0)) {
// print out bus and frame
//printFrame(&frame0, 0);
CAN1.sendFrame(frame0);
// Serial.println("Frame sent from CAN0 to CAN1");
// lastCan0Frame = millis();
// fill_solid(leds, NUM_LEDS, CRGB::Red);
// FastLED.show();
}

CAN_FRAME frame1;

if (CAN1.available() && CAN1.read(frame1)) {
// print out bus and frame
// printFrame(&frame1, 1);
CAN0.sendFrame(frame1);
// Serial.println("Frame sent from CAN1 to CAN0");
// lastCan1Frame = millis();
// fill_solid(leds, NUM_LEDS, CRGB::Blue);
// FastLED.show();

}

}

Any ideas as to what I might be doing wrong in my calls to the library?

In addition, I learned that initializing the TWI modules CAN0 then CAN1 caused CAN0 to cease being able to transmit and receive while causing the above code to echo CAN1 receptions back to CAN1 (as opposed to CAN0).

Thank you for any comments and/or help. Bill

[TechOverflow]

Hi Bill,
This repo unfortunately seems to be dead.
Have you tried my forked version of this library? https://github.com/TechOverflow/esp32_can
Also, try rolling back to Arduino Release v3.2.1 based on ESP-IDF v5.4.2
ESP-IDF 5.5.2+ (Arduino Release v3.3.0+) has updated the TWAI driver for CAN-FD and they're now calling the previous TWAI driver "Legacy TWAI Driver". The new driver could be causing these issues.

[lolachampcar]

Will do and thank you!

[lolachampcar]

For completeness, I updated the ESP32_can library as suggested above.
Using ESP32C6 Dev Module as the board choice, I opened the CANipulator_test_forwarder example (which confirmed to me the library was updated).

I confirmed there were compile errors with the SmartLED so I commented out all references. The header file was the issue.
The error was
\Users\bill\Documents\Arduino\libraries\SmartLeds\src/SmartLeds.h:300:39: note: in expansion of macro '_SMARTLEDS_SPI_HOST'
300 | auto ret = spi_bus_initialize(_SMARTLEDS_SPI_HOST, &buscfg, _SMARTLEDS_SPI_DMA_CHAN);
| ^~~~~~~~~~~~~~~~~~~

I compiled and deployed the code and confirmed that (1) CAN0 was not functional and (2) messages to CAN1 were reflected back onto CAN1.

I reversed the CAN init order as follows

// setup CAN pins and speed
CAN1.setCANPins(GPIO_NUM_18, GPIO_NUM_19);
CAN1.begin(500000);
CAN1.watchFor();
CAN0.setCANPins(GPIO_NUM_16, GPIO_NUM_17);
CAN0.begin(500000);
CAN0.watchFor();

0x007 message ID CAN frames are passed from CAN1 to CAN0 and CAN0 to CAN1 correctly without issue.

Changing the message ID from 0x007 to 0x008 causes CAN0 to CAN1 passthough attempts to spew CAN1 messages as before.
Changing the message to 0x008 still works CAN1 to CAN0 passthrough

Appreciate the guidance but the issue remains.

[TechOverflow]

Could this be a SavvyCAN issue?
Have you tried having the Arduino sketch produce the messages and using SavvyCAN to watch only?

[lolachampcar]

I can try that but the issue is the ESP32 is writing multiple messages out one bus when the ID from the incoming bus in incremented by one.

I'm also trying to ferrit out using ESP-IDF in Visual Studio (with PlatformIO) and employ the dual can bus instance init.

[lolachampcar]

By chance do you have an image of the firmware that was on the board when I received it. It would be helpful to try your pre-compiled version as, if it works, it is clearly something I am doing on my end. Thanks, Bill

[lolachampcar]

For those interested in using PlatformIO and the ESP-IDF on the CANipulator board, this is what ended up working for me. I started with the ESP32-C6 hello world example and changed the memory size to 4Mb (for the CANipulator board) from the 8Mb on the dev board. I have yet to get in circuit debugging running but can now download code from PlatformIO.

[env:esp32-c6-devkitc-1]
platform = espressif32
board = esp32-c6-devkitc-1
framework = espidf
monitor_speed = 115200
board_build.flash_size = 4MB
board_upload.flash_size = 4MB
board_build.flash_mode = qio