A1616E armcc compile error

I got compile error "Error: A1616E: Instruction, offset, immediate or register combination is not supported by the current instruction set"

For below routine 

__asm uint32_t A(void)
{
    MRS R0, MSP       ====> line pointed by error message
    LDR R0, [R0,#8]

    ...


    BX lr
}

for both Arm compiler 4.1 and 5.06.  What I am missing here?  thanks...

Parents Reply Children