A0 Help Can not showing available

[Mission]

I have been working trying to get an A0 to run a project I am currently working on. I have used the M2 for the project, but do not need the extra inputs that the M2 offers. With that being said, I am hitting a roadblock. Essentially, the can never shows available nor does it receive any incoming messages. I have looked everywhere for help on the A0 and have come up short. I am attaching my simplified code below. In the IDE I am setting it as the ESP32 Dev Module. It compiles with no problem. However, it never appears to enter the can0.available area. I have commented that out and asked it to only output the Can0.read(incoming) and it still would never output anything but 0 for the incoming.id. I have a can logger on and have ensured I am getting plenty of traffic over the bus. The speed is for sure 500k also. I have also tried adding the watchfor command and setting up mailboxes. None of this is needed for the M2. So, I am a little confused. Any help would be appreciated.

#include <esp32_can.h>

CAN_FRAME incoming;
CAN_FRAME outgoing;


void setup() {
  delay (1000);

  Serial.begin(115200);
  Serial.flush();

  Can0.begin (CAN_BPS_500K);

  delay(1000);
}


void loop() {

  if (Can0.available() > 0) {
    Serial.println("Can Available");
    Can0.read(incoming);
    Serial.println(incoming.id);
  }

}

[Mission]

Today, I reached out to Macchina and they sent me a sample sketch. Even the sample sketch they provided would not initialize the Can0. Has anyone had this problem before?

[redheadedrod]

I would say check out this thread… Maybe something there will help…

Very Simple BLE<->ISO-TP A0 firmware

Hi all, just wanted to share something I’ve been working on targeting the A0: https://github.com/bri3d/esp32-isotp-ble-bridge . This is a super simple mash-up of open-source ISO-TP code and the ESP-IDF (FreeRTOS ESP toolchain) examples for BLE “Serial” using GATTs and the ESP-IDF “TWAI” drivers (CAN in copyright disguise). To build it, you need the ESP-IDF toolchain and then it’s just “idf.py flash” . Right now, it works perfectly for simple multi-frame ISO-TP messages with flow control, on b…

[Mission]

Thank you for that. I am in contact with him to try and figure out what is going on. From what I gathered from Earl at Macchina, there was a change from the beta A0 to the production unit. In the production unit, they used a TJA1042 transceiver. Once this was added, none of the sketches they have linked on their site work.

For anyone else having this issue, the below needs to be added to the setup. This is due to a standby pin needing to be pulled low to exit standby mode.

pinMode(21, OUTPUT);
digitalWrite(21, LOW);