SWI - Software Interrupt ;flags(I)

SWI ;PC <= PC + 1 ;(INH) inherent addressing

;push PCL ;SP <= SP - 1

;push PCH ;SP <= SP - 1

;push X ;SP <= SP - 1

;push A ;SP <= SP - 1

;push CCR ;SP <= SP - 1

;I <= 1

;PCH <= (swi vector_hi)

;PCL <= (swi vector_low)

The address of the SWI vector can be expressed as $xFFC :$xFFD, where x is 1 or 3 depending on the version of 68HC05 being used. This instruction is not maskable by the I bit.