IBM 6400 Series, Setup Manual

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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.
Figure 67. Resistor Locations
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:
Table 10. Terminating Resistor Configurations
Configuration Pull-Up (RP1) Pull-Down (RP2)
Factory Default 470 ohm 1K ohm
Alternate 1 220 ohm 330 ohm
Alternate 2 1K ohm none
RP1
Default: 470 ohm
Alt 1: 220 ohm
Alt 2: 1K ohm
RP2
Default: 1K ohm
Alt 1: 330 ohm
Alt 2: none