Send a byte to RS232

#include "../orix/src/include/orix.h"
#include "../orix/src/include/macro.h"
; set the header
; for information, if buffer is full, (when you send many A and the remote machine does not accept the bytes, the telestrat crashes).
; For instance, there is no way to detect if the buffer is full
; anyway, we can enlarge the buffer size.
lda #"A" ; send A