Custom Engineering PLUS II User Manual page 40

2. INTERFACES
For parallel TTL interface printer the communication signals are: 8 bit DATA BUS, STROBE (indicate the data
validity) and BUSY (indicate that the printer is ready to receive data).
Transmission format
D0...D7
STROBE
BUSY
Flow diagram
ERROR
(Fig.2.7)
2-8 PLUS II
User Manual
VALID DATA
SI
OUT DATA
OUT STROBE=0
SI
OUT STROBE=1
VALID DATA
START
TIMEOUT
> 1 sec.
NO
NO
BUSY=1
SI
TIMEOUT
> 4 sec.
NO
NO
BUSY=0
RETURN