Interfaces8–26
Switching Interfaces
As previously mentioned, switching from one interface to the other requires a
simple change of the printer’s input/output (I/O) cable, terminating resistors,
and Configuration Option 66 (refer to Switching Interfaces in this chapter).

Interface Cables

The Centronics or Dataproducts interface cable must not exceed 40 feet in
length and must allow the transmission of signals having standard TTL logic
levels (0.0V to +0.5 low and +2.4V to +5.25V high). For minimum electrical
noise, use shielded cable and ground the shield.

Terminating Resistors

The Centronics parallel interface requires that 1000–ohm resistor packs be
installed at Parallel Controller PCBA coordinates 15 C and 18C as shown in
Figure 8–5. Typical circuits using the resistors are shown in Figure 8–6.
The Dataproducts interface requires the 220–ohm resistor pack at coordinates
18C and a 330–ohm pack at coordinates 17C. A 1000–ohm pack is installed
at location 15C.