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Semiconductor Group
9
1998-05-01
C161RI
PORT0:
P0L.0 –
P0L.7,
P0H.0 -
P0H.7
38 –
45,
48 –
55
40 –
47,
50 –
57
I/O
PORT0 consists of the two 8-bit bidirectional I/O ports P0L
and P0H. It is bit-wise programmable for input or output via
direction bits. For a pin configured as input, the output driver
is put into high-impedance state.
In case of external bus configurations, PORT0 serves as the
address (A) and address/data (AD) bus in multiplexed bus
modes and as the data (D) bus in demultiplexed bus modes.
Demultiplexed bus modes:
Data Path Width:
8-bit
P0L.0 – P0L.7:
D0 – D7
P0H.0 – P0H.7:
I/O
Multiplexed bus modes:
Data Path Width:
8-bit
P0L.0 – P0L.7:
AD0 – AD7
P0H.0 – P0H.7:
A8 - A15
16-bit
D0 - D7
D8 - D15
16-bit
AD0 - AD7
AD8 - AD15
PORT1:
P1L.0 –
P1L.7,
P1H.0 -
P1H.7
56 –
63,
66 –
73
58 -
65,
68 -
75
I/O
PORT1 consists of the two 8-bit bidirectional I/O ports P1L
and P1H. It is bit-wise programmable for input or output via
direction bits. For a pin configured as input, the output driver
is put into high-impedance state. PORT1 is used as the 16-
bit address bus (A) in demultiplexed bus modes and also
after switching from a demultiplexed bus mode to a
multiplexed bus mode.
RSTIN
76
78
I
Reset Input with Schmitt-Trigger characteristics. A low level
at this pin for a specified duration while the oscillator is
running resets the C161RI. An internal pullup resistor permits
power-on reset using only a capacitor connected to
V
SS
.
In bidirectional reset mode (enabled by setting bit BDRSTEN
in register SYSCON) the RSTIN line is internally pulled low
for the duration of the internal reset sequence upon a
software reset, a WDT reset and a hardware reset.
1)
RSTOUT 77
79
O
Internal Reset Indication Output. This pin is set to a low level
when the part is executing either a hardware-, a software- or
a watchdog timer reset. RSTOUT remains low until the EINIT
(end of initialization) instruction is executed.
NMI
78
80
I
Non-Maskable Interrupt Input. A high to low transition at this
pin causes the CPU to vector to the NMI trap routine. When
the PWRDN (power down) instruction is executed, the NMI
pin must be low in order to force the C161RI to go into power
down mode. If NMI is high, when PWRDN is executed, the
part will continue to run in normal mode.
If not used, pin NMI should be pulled high externally.
Pin Definitions and Functions
(cont’d)
Symbol
Pin No.
TQFP
Pin No.
MQFP
Input
Outp
Function