Pinout and signal descriptions – Digi NS9750 User Manual
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Pinout and signal descriptions
Each pinout table applies to a specific interface, and contains the following
information:
More detailed signal descriptions are provided for selected modules.
System Memory interface
Heading
Description
Pin #
Pin number assignment for a specific I/O signal
Signal
Pin name for each I/O signal. Some signals have multiple function modes and are
identified accordingly. The mode is configured through firmware using one or more
configuration registers.
_n in the signal name indicates that this signal is active low.
U/D
U or D indicates whether the pin is a pullup resistor or a pulldown resistor:
U — Pullup (input current source)
D — Pulldown (input current sink)
If no value appears, that pin is neither a pullup nor pulldown resistor.
I/O
The type of signal: input, output, or input/output.
OD (mA)
The output drive of an output buffer. NS9750 uses one of three drivers:
2 mA
4 mA
8 mA
Pin #
Signal Name
U/D
OD
(mA)
I/O
Description
A21
addr[0]
8
O
Address bus signal
B20
addr[1]
8
O
Address bus signal
C19
addr[2]
8
O
Address bus signal
A20
addr[3]
8
O
Address bus signal
B19
addr[4]
8
O
Address bus signal
Table 3: System Memory interface pinout