Epson 5000/5500 - Manual (Page 121)

Interface Specifications
Signal Return
Description
P i n Pin
Signal Direction
33 GND Same as for pins 19-30.
3 4 NC Not used.
35 O U T Pulled up to 5 V through 3.3 Kohm
36 SLCT IN I N The DC1/DC3 code is valid only when
this signal is HIGH. This signal is always
LOW.
Note:
The column heading “Direction” refers to the direction of
signal flow as viewed from the printer.
“Return” denotes the twisted-pair return, to be connected at
signal ground level. For the interface wiring, be sure to use a
twisted-pair cable for each signal and to complete the
connection on the return side.
All interface conditions are based on the TTL level. Both the
rise and fall times of each signal must be less than 0.2
microseconds.
Data transfer must be carried out by observing the ACKNLG
or BUSY signal. (Data transfer to this printer can be carried
out only after receipt of the ACKNLG signal or when the
BUSY signal is LOW.)
7-12 Technical Specifications