User Manual

© Sealevel Systems, Inc.
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PIO-48.PC104 User Manual
Pull Ups
Eight resistors are installed to provide pull-ups to the input ports. These are installed
on all ports. The pull-up resistors are rated at 10K ohms. Figure 4 below provides
the resistors and corresponding port. The resistors ensure that no line is floating
which is not connected. This provides consistent biasing on all un-terminated lines.
Resistor Corresponding Port
R34-R41 Port A1
R42-R49 Port B1
R50-R53 Port C1L
R54-R57 Port C1U
R1-R8 Port A2
R9-R16 Port B2
R17-R20 Port C2L
R21-R24 Port C2U