PlatformIO Linker error when USBCON/CDC Enabled

[gateseee]

Hello. I struggled a long time now with the STM32 to get it running via standard USB connection without using the STlink. For doing this, i had to add some flags in platformio.ini

[env:bluepill_f103c8]
platform = ststm32
board = bluepill_f103c8
framework = arduino
upload_protocol = dfu
build_flags = 
    -D HAL_CAN_MODULE_ENABLED
    -D USBCON
    -D PIO_FRAMEWORK_ARDUINO_ENABLE_CDC
    -D HAL_PCD_MODULE_ENABLED
    -D USBD_VID=0x1EAF
    -D USBD_PID=0x0004
    -D USB_PRODUCT=\"bluepill\"

lib_deps = pazi88/STM32_CAN@^1.1.0

If i'm compiling now, as excample this minimal version:

#include "STM32_CAN.h"
STM32_CAN Can( CAN1, ALT );
void setup() {
  return; 
}
void loop() {
  return; 
}

It throw's the following errors:

Processing bluepill_f103c8 (platform: ststm32; board: bluepill_f103c8; framework: arduino)

Verbose mode can be enabled via -v, --verbose option CONFIGURATION: https://docs.platformio.org/page/boards/ststm32/bluepill_f103c8.html PLATFORM: ST STM32 (15.6.0) > BluePill F103C8 HARDWARE: STM32F103C8T6 72MHz, 20KB RAM, 64KB Flash DEBUG: Current (stlink) External (blackmagic, cmsis-dap, jlink, stlink) PACKAGES:

• framework-arduinoststm32 @ 4.20400.0 (2.4.0)
• framework-cmsis @ 2.50700.210515 (5.7.0)
• tool-dfuutil @ 1.11.0
• toolchain-gccarmnoneeabi @ 1.90201.191206 (9.2.1) LDF: Library Dependency Finder -> https://bit.ly/configure-pio-ldf LDF Modes: Finder ~ chain, Compatibility ~ soft Found 13 compatible libraries Scanning dependencies... Dependency Graph |-- STM32_CAN @ 1.1.0 Building in release mode Compiling .pio\build\bluepill_f103c8\src\main.cpp.o Linking .pio\build\bluepill_f103c8\firmware.elf c:/users/thed0/.platformio/packages/toolchain-gccarmnoneeabi/bin/../lib/gcc/arm-none-eabi/9.2.1/../../../../arm-none-eabi/bin/ld.exe: .pio/build/bluepill_f103c8/libFrameworkArduino.a(usbd_conf.c.o): in function USB_LP_CAN1_RX0_IRQHandler': usbd_conf.c:(.text.USB_LP_CAN1_RX0_IRQHandler+0x0): multiple definition ofUSB_LP_CAN1_RX0_IRQHandler'; .pio/build/bluepill_f103c8/lib7ea/libSTM32_CAN.a(STM32_CAN.cpp.o):STM32_CAN.cpp:(.text.USB_LP_CAN1_RX0_IRQHandler+0x0): first defined here c:/users/thed0/.platformio/packages/toolchain-gccarmnoneeabi/bin/../lib/gcc/arm-none-eabi/9.2.1/../../../../arm-none-eabi/bin/ld.exe: .pio/build/bluepill_f103c8/libFrameworkArduino.a(usbd_conf.c.o): in function USB_HP_CAN1_TX_IRQHandler': usbd_conf.c:(.text.USB_HP_CAN1_TX_IRQHandler+0x0): multiple definition ofUSB_HP_CAN1_TX_IRQHandler'; .pio/build/bluepill_f103c8/lib7ea/libSTM32_CAN.a(STM32_CAN.cpp.o):STM32_CAN.cpp:(.text.USB_HP_CAN1_TX_IRQHandler+0x0): first defined here collect2.exe: error: ld returned 1 exit status *** [.pio\build\bluepill_f103c8\firmware.elf] Error 1

As soon as i remove the USB build flags, its compiling.

Does anyone have an Idea?

Chris

[pazi88]

On F103 the usb and CAN share registers. So you can't use those at the same time. It's hardware limitation, so there is nothing you can do for it.

[gateseee]

Is there any documentation about that, that i can dig further?

[pazi88]

Is there any documentation about that, that i can dig further?

There is something if you google the issue. But also if you carefully read the F103 datasheet from ST, there is indeed some registers that overlap between USB and CAN. Don't remember which ones, because it's so long time since I checked.

[gateseee]

Thanks. Got it to work now. I am using an ESP32 to read the Serial data sent from the STM32 until my FTDI breakout board arrives. Flashing is done via STlink.

If someone is going to try the same: In your STM32 code, just change this in the setup, and then print whatever you want

void setup() {
    Serial.setRx(PA10);
    Serial.setTx(PA9);
    Serial.begin(250000);
   //..... 
}

void loop() {
// do whatever you want... 
Serial.println("Test123...."); 
// do whatever you want... 
}

On ESP32 (and i assume on any other Arduino Compatible board) just do this, and then monitor the ESP32's output, which contains the STM32's messages.

// STM32 RX = PIN PA10 connects to ESP32 TX = 2
// STM32 TX = PIN PA9  connects to ESP32 RX = 15

const int TX_PIN = 2;
const int RX_PIN = 15; 

HardwareSerial SerialSTM32(2);

void setup() {
  Serial.begin(250000); 
  SerialSTM32.begin(250000, SERIAL_8N1, RX_PIN, TX_PIN);
}

void loop() {
  while (SerialSTM32.available() > 0) {
     Serial.print(char(SerialSTM32.read()));
  }
}

For my tests now it worked fine, but its not the optimal solution of course.

[pazi88]

Great to know. I'll close this issue, since there isn't anything we can do for the hardware limitations.