Rice Lake Datamax-ONeil I-Class Printer - Manual (Page 130)

120 I-Class
GPIO Pin Configuration
(as viewed from the rear of the printer)
External Start of Print Control
Connections for an external Start
of Print control can be made (1)
directly to Pin 8 using a TTL-
level input or (2) with an
interface circuit similar to the
one shown right. For additional
interfacing requirements, see the
table below.
GPIO Port Specifications*
V
in
max 5.5 VDC maximum input into any pin
V
IH
3.8 VDC minimum (high level input voltage)
V
IL
1.65 VDC maximum (low level input voltage)
I
OH
-8 mA typical, - 25 mA maximum (high level output current)
I
OL
8 mA typical 25 mA maximum (low level output current)
V
OH
I
OH
= -8 mA, minimum 3.8 VDC
V
OL
I
OL
= 8 mA, maximum .44 VDC
*See the SN74AHC244 data sheet for more information.