Der Buffer für Serialin

_RS_HEAD_PTR0 , a byte counter that stores the head of the buffer
_RS_TAIL_PTR0 , a byte counter that stores the tail of the buffer.
_RS232INBUF0 , an array of bytes that serves as a ring buffer for the received characters.

Der Buffer für Serialout

_RS_HEAD_PTRW0 , byte that stores the head of the buffer
_RS_TAIL_PTRW0 , byte that stores the tail of the buffer
_RS232OUTBUF0, array of bytes for the ring buffer that stores the printed data.

Mit vergleichen Head / Tail kannst du sehen was voll und was leer ist