Flowcode Support Board

I've modified your program a little to give us more information with the LED flash.
Can you try this and let me know what the LED does?
Please ensure you use the STARM_CAL_RTC.c from the "STM32F QUESTIONS" thread...
https://www.flowcode.co.uk/forums/viewt ... 918#p18918
Into directory ...
C:\ProgramData\MatrixTSL\FlowcodeV10\CAL\STARM

I just need it to see if the code runs

Yes, but my version will let me know where it stops.
Can you run it and tell me what the LED does?
E.g. LED on, LED off. LED on permanently

I only see 1 flash of 1 second and then always off, if in the code I invert the position of the UART block with RTC no flashing always off

by entering the C code
__HAL_RCC_PWR_CLK_ENABLE();
HAL_PWR_EnableBkUpAccess();
__HAL_RCC_LSE_CONFIG(RCC_LSE_ON);
__HAL_RCC_RTC_CONFIG(RCC_RTCCLKSOURCE_LSE);
of the old "STM32F QUESTIONS" thread works still with the old STARM_CAL_RTC.c, now I try with the original FC10 one

even with the original FC10 STARM_CAL_RTC.c adding the lines of code works

Now I have another type of problem, everything works fine if I use serial 1 but if I put the software serial for example the tx port C13 nothing comes out, C14 arrives ......, C15 nothing comes out, A0 seems to work fine, are there preferable pins for the software serial? I haven't tried other pins yet

Well done, thanks for that.
I'll compare that with the modified CAL file, not sure when I'll next get some time to do that. But at least you now have a functional work around.

Ah right. I guess we need to look at the Blackpill circuit diagram and 411 datasheet to answer that one