Epson EPL-9000 Service Manual page 25

General Description
1-4 shows the parallel interface state switch diagram.
Compatibility Mode
Forward
Data
Transfer
No data sent
I
AUTO
FE ED= LOW
Figure 1-4. Parallel Interface State Switch Diagram
ACK and
ERR= LOW
Service
IN= LOW
ERR= LOW
Sending data
AUTO
FFFD LOW
Request to
send data
AUTO