Re: RE : [fpc-pascal] Variable alignment in arm-embedded

[Koenraad Lelong]

On 08-06-12 06:45, Ludo Brands wrote:

Handcrafted alignment:

var
   ReservedBlock:array[0..$1FF] of byte;
   IntVectors:pointer;
begin
   IntVectors:=pointer((ptruint(@ReservedBlock[0])+$100) and not $ff);
End;

Or dynamic:

Var
   pReservedBlock,IntVectors:pointer;
begin
   Getmem(pReservedBlock,$200);
   IntVectors:=pointer((ptruint(pReservedBlock)+$100) and not $ff);
End;

Thanks Ludo,

I'll take that as a starting point. I hope I will not need the "lost" 
256 bytes in the future.
I can replace the IntVectors-pointer with a pointer to a record of 
pointers, isn't it ? That way I have a clearer view of what vectors I'm 
working with.

TIntVectorTable = record of
        NMI_Handler,
        HardFault_Handler,
        MemManage_Handler,
        BusFault_Handler,
        UsageFault_Handler,
        SWI_Handler,
        DebugMonitor_Handler,
        PendingSV_Handler,
        Systick_Handler,
(* STM32 specific Interrupt Numbers *)
        WWDG_Handler,
        PVD_Handler,
        ...
        USBWakeUp_Handler : pointer;
end {TIntVectors};

var
 IntVectors : ^TIntVectorTable;
 ReservedBlock:array[0..$FF+SizeOf(TIntVectorTable)] of byte;

procedure SystickProc; interrupt;

begin
...
end;

begin
  IntVectors:=pointer((ptruint(@ReservedBlock[0])+$100) and not $ff);
  IntVectors^.SystickHandler:=@SystickProc;
...
end.

Koenraad
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