[fpc-pascal] Variable alignment in arm-embedded

[Ludo Brands]

> Hi,
> 
> I want to make an interrupt-vector-table for the cortex-M3 processor. 
> When I read the docs of the processor good, the start of that table 
> needs to be on a multiple of $100 bytes in memory. Since with 
> FPC there 
> seems no way of getting that table in flash I need to have it in RAM. 
> But how can I have the table at those $100-bytes multiple ? I 
> found an 
> ALIGN directive, but that's limited to 32 bytes.
> Any suggestions ?
> I had hoped that the first variable would be at the first location in 
> RAM and the first variable in the startup-code is that vector-table. 
> Unfortunatly, my hope was in vain.
> 
> Any help ?
> 

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;


Ludo