Terminating Resistor Configurations - IBM 6400 Setup Manual

Chapter 5
IEEE 1284 Parallel Interface

Terminating Resistor Configurations

The factory equips the printer with several resistors that are used for parallel
interface configurations and are suitable for most applications. These 470
ohm pull-up and 1K ohm pull-down terminating resistors are located at RP1
and RP2, shown in Figure 67.
If the values of these terminating resistors are not compatible with the
particular interface driver requirements of your host computer, you may need
to install resistors with different pull-up and pull-down values.
NOTE: Must be installed by an IBM service representative.
The shipping kit for this printer includes 220 ohm pull-up and 330 ohm pull-
down alternate terminating resistors. If you install the 220 ohm pull-up
resistor, you must also install the 330 ohm pull-down resistor. Table 10 lists
the three terminating resistor configurations you can install:
222
Figure 67. Resistor Locations
Table 10. Terminating Resistor Configurations
Configuration Pull-Up (RP1)
Factory Default 470 ohm
Alternate 1 220 ohm
Alternate 2 1K ohm
RP1 Default: 470 ohm
Alt 1: 220 ohm
Alt 2: 1K ohm
RP2 Default: 1K ohm
Alt 1: 330 ohm
Alt 2: none
Pull-Down (RP2)
1K ohm
330 ohm
none