NEC PD78058FY(A) Network Card User Manual


 
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CHAPTER 3 PIN FUNCTION (
µ
PD78058F SUBSERIES)
3.2.5 P40 to P47 (Port 4)
These are 8-bit input/output ports. Besides serving as input/output ports, they function as an address/data bus.
The test input flag (KRIF) can be set to 1 by detecting a falling edge.
The following operating mode can be specified in 8-bit units.
(1) Port mode
These ports function as 8-bit input/output ports. They can be specified in 8-bit units for input or output ports
by using the memory expansion mode register (MM). When they are used as input ports, on-chip pull-up
resistors can be used by defining the pull-up resistor option register L (PUOL).
(2) Control mode
These ports function as low-order address/data bus pins (AD0 to AD7) in external memory expansion mode.
When pins are used as an address/data bus, the on-chip pull-up resistor is automatically disabled.
3.2.6 P50 to P57 (Port 5)
These are 8-bit input/output ports. Besides serving as input/output ports, they function as an address bus.
Port 5 can drive LEDs directly.
The following operating modes can be specified bit-wise.
(1) Port mode
These ports function as 8-bit input/output ports. They can be specified bit-wise as input/output ports with port
mode register 5 (PM5). When they are used as input ports, on-chip pull-up resistors can be used by defining
the pull-up resistor option register L (PUOL).
(2) Control mode
These ports function as high-order address bus pins (A8 to A15) in external memory expansion mode. When
pins are used as an address bus, the on-chip pull-up resistor is automatically disabled.
3.2.7 P60 to P67 (Port 6)
These are 8-bit input/output ports. Besides serving as input/output ports, they are used for control in external
memory expansion mode. P60 to P63 can drive LEDs directly.
The following operating modes can be specified bit-wise.