Executing independently compiled code in RAM.

[VNilo]

I have a device that must execute precompiled functions which are copied to a place in RAM.

Function calling:

PLC_main = (pFunc_main) 0x30000001; 
PLC_main();

Compied function:

    PLC_1
        0x30000000:    4811        .H      LDR      r0,[pc,#68] ; [0x30000048] = 0x30020004
        0x30000002:    6800        .h      LDR      r0,[r0,#0]
        0x30000004:    1c80        ..      ADDS     r0,r0,#2
        0x30000006:    4910        .I      LDR      r1,[pc,#64] ; [0x30000048] = 0x30020004
        0x30000008:    6008        .`      STR      r0,[r1,#0]
        0x3000000a:    4608        .F      MOV      r0,r1
        0x3000000c:    6800        .h      LDR      r0,[r0,#0]
        0x3000000e:    4770        pG      BX       lr

But after calling this function, program jumps to some place in flash and runs from there.

Is it possible to make a precompiled function to return to a place where it is called ?

[Tesla DeLorean]

What MCU?

You should be able to step into the RAM code and return via BX​ LR

Try 0x20000000 SRAM

[VNilo]

STM32H743 mcu. Keil cannot run by step since function called, it begins to run, but if i stop it manually, i see code execution from flash. Not a code that placed after a function call, because i have a breakpoint there. It looks like this function returns but not to a place where it was called.