HD64570 Datasheet, PDF (196/469 Pages) Hitachi Semiconductor – Serial Communications Adaptor

Initialization by reset
No space detected
"RX enable" issued
RX disable
Start bit
state
search state
After wait
Half-bit
cycle wait state
Space detected
No framing error
"RX reset", "RX disable"
or "channel reset" issued
in any stale
NG (mark)
or break detected
after assembly
Framing error
detected,
but no break
detected after
Start bit
check state
OK (space)
Character ^assembly
assembly state
OK
Mark
(mark) detected
Break detected
(1/1 clock
after assembly
mode)
No mark
detected
Break end
wait state
Mark detected
(other than 1/1 clock mode)
NG (space)
Break end
check state
Note: Command names are enclosed in double quotation marks ("").
Figure 5.15 State Transition Diagram for Reception in Asynchronous Mode
Rev. 0, 07/98, page 180 of 453