I'm trying out STM32CubeIDE, and I've been trying to get it to work with the GDB QEMU debugging plugin that's part of the Eclipse CDT package. I've been able to create the project and debug configuration for my STM32F4-Discovery board, and the debugger partially launches, however, just as the simulator starts up, the GUI window it creates suddenly crashes and I get this error:
Error in final launch sequence
Failed to execute MI command:
-target-select remote localhost:1234
Error message from debugger back end:
Truncated register 18 in remote 'g' packet
Failed to execute MI command:
-target-select remote localhost:1234
Error message from debugger back end:
Truncated register 18 in remote 'g' packet
Truncated register 18 in remote 'g' packet
I think this is caused by some mismatch between the CDT plugin I installed and the GCC toolchain that shipped with my installation of Ubuntu 20.04. However, I'm not sure how to fix this.
Is there anything I try to fix this?
So it looks like there were a couple factors as to why this wasn't working. First off, the error messages that I was getting immediately after the GUI debugger terminated were due to an incorrect installation of the arm-none-eabi-gdb package. In order to fix this, I downloaded the package from the ARM site and followed the instructions detailed here. After installing the arm-none-eabi-gdb package again, I went into the project debug configuration settings, navigated to the "debugger" tab in this window, and then changed the GDB executable path from the variables the IDE had set for me to the actual GDB executable path (in this case /usr/bin/arm-none-eabi-gdb).
After that was done, the debugger would no longer immediately terminate, but I was still getting some errors in console shortly after it started (see below). In addition, the debugger GUI would produce no meaningful output, and Ubuntu would warn that the process had frozen.
NVIC: Bad read offset 0xd88
qemu-system-gnuarmeclipse: Attempt to set CP10/11 in SCB->CPACR, but FP is not supported yet.
To solve this, I right clicked the project in the project explorer panel of the IDE, then went to C/C++ build section, then to the Settings section under that, and then finally to the "Tool settings" section of this menu. Under "MCU settings", there are two options for "Floating point unit" and "Floating point ABI", which I changed to "None" and "Software implementation" respectively. After saving these configuration changes, I went to the system_stm32f4xx.c file under the src/ directory of the project, and commented out these lines:
/* FPU settings ------------------------------------------------------------*/
#if (__FPU_PRESENT == 1) && (__FPU_USED == 1)
SCB->CPACR |= ((3UL << 10*2)|(3UL << 11*2)); /* set CP10 and CP11 Full Access */
#endif
After that, I cleaned the project, rebuilt it, and relaunched the debugger. It then functioned normally.