Oki ML420 - Communication Procedure Flowchart; Mode a

42113901TH01 Rev.3 128 /
Oki Data CONFIDENTIAL
2.3 Communication Procedure Flowchart
2.3.1 Mode a
Ready/Busy
Received one
character?
Yes
Is DSR valid?
No
Buffer overflow?
Error?
Parity error
No error
Store the received
character in buffer.
Is the
printer in DESELECT
state or is the paper
low?
No
No
Yes
Yes
No
DSR High?
Yes
Store 40 H in buffer.
Yes
Yes
No
Yes
Is remaining
buffer space ≤ 256?
Yes
No
Turn on the SSD signal.
Turn off the SSD signal.
Printer busy?
No
Output one character from the
buffer to printer.
No
Yes
No
Has 200 ms or
1s elapsed after SSD was
turned on?
Is remaining
buffer space > 256 during
receive time out?
Figure C-2