crt1.S

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 * Balint Cristian <cristian dot balint at gmail dot com>
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 * TinnyModbus
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/*

  crt1.S (BootLoader init)

*/



#include <avr/io.h>

#ifdef __AVR_HAVE_JMP_CALL__
  #define XJMP jmp
#else
  #define XJMP rjmp
#endif

#define XCALL rcall

  ;
  ; no vector table
  ; just jump to __init
  ;
  .section .vectors, "ax", @progbits
  .global  __vectors
    XJMP    __init
    .func   __vectors
    .endfunc

  .section .init0,   "ax", @progbits
    .weak   __init

      __init:
          .weak  __heap_end
          .set   __heap_end, 0
          .weak  __stack
          .set   __stack, RAMEND

  ;
  ; dont reset stack pointer
  ; will be done in main()
  ;
  .section .init2,   "ax", @progbits
          CLR  R1
          ;OUT  0x3f, R1
          ;LDI  R28,  lo8(__stack)
          ;LDI  R29,  hi8(__stack)
          ;OUT  0x3d, r28
          ;OUT  0x3e, r29

  .section .init9,   "ax", @progbits
          XJMP  main