I'm using S12 communicate with S08 via SCI。When S08 enable the break detect interrupt(set SCIxS2.LBKDE),no ISR reply. See the wave on RX pin with 13clk low, and in debug mode, the SCIxS2.LBKDIF is set. But can not jmp to the ISR.
When S08 disable the break detect inerrupt(clr SCIxS2.LBKDE),the S08 will jmp to ISR with receiver buffer full and Framing Error. I think the baud rate is the same as S12.