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CHAPTER 2 PIN FUNCTIONS
(7) P60 through P63 (Port 6) ... 3-state I/O
Port 6 is a 4-bit I/O port with an output latch. This port can be set in the input or output mode in 1-bit units by using
port 6 mode register (PM6). Each pin is provided with a software programmable pull-up resistor.
In addition to as an I/O port, this port also functions as the high-order address bus (A16 through A19) if so specified
by the memory expansion mode register when an external memory or I/O is connected.
When RESET is input, this port is set in the input mode (output high-impedance status), and the contents of the
output latch are undefined.
(8) P70 through P77 (Port 7) ... Input
Port 7 is an 8-bit input port. In addition to as input port pins, its pins also function as an A/D converter analog input
(low-order 8 channels) pins (ANI0 through ANI7), and can always input analog signals. This port is set in the analog
input mode by using A/D converter mode register (ADM).
The level of each pin of this port can always be read or tested, regardless of the multiplexed function.
(9) P80 through P87 (Port 8) ... Input
Port 8 is an 8-bit input port. In addition to functioning as input port pins, its pins also functions as an A/D converter
analog input (high-order 8 channels) pins (ANI8 through ANI15), and can always input analog signals. This port
is set in the analog input mode by using A/D converter mode register (ADM).
The level of each pin of this port can always be read or tested, regardless of the multiplexed function.
(10) P90 through P94 (Port 9) ... 3-state I/O
Port 9 is a 5-bit I/O port with an output latch. This port can be set in the input or output mode in 1-bit units by using
port 9 mode register (PM9). Each pin is provided with a software programmable pull-up resistor.
In addition to the I/O port function, port 9 also functions as control signal pins (refer to
Table 2-5
). P90 through
P93 function as read/write strobe signals and an address strobe signal if so specified by the memory extension
mode register (MM) when an external memory or I/O is connected. P94 functions as a wait signal input pin if so
specified by port 9 mode control register (PMC9).
When RESET is input, this port is set in the input mode (output high-impedance status), and the contents of the
output latch are undefined.
Table 2-5. Operation Mode of Port 9
Pin Name
Port Mode
Control Signal I/O Mode
Manipulation to Use Port 9 as Control Pins
P90
I/O Port
RD
Specifying external memory expansion mode by
P91
LWR
MM0 through MM3 bits of MM
P92
HWR
P93
ASTB
P94
WAIT
Setting of PMC94 bit of PMC9 to 1
Remark
For details, refer to
CHAPTER 17 LOCAL BUS INTERFACE FUNCTION
.