172
Mitsubishi microcomputers
M16C / 62T Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Programmable I/O Port
Figure 1.23.9. Example connection of unused pins
Microcomputer
VSS
In single-chip mode
Microcomputer
In memory expansion mode
or in microprocessor mode
Port P6 to P10
(except for P85)
Input mode
Output mode
NMI
BHE
HOLD
AVSS
VREF
Open
VCC
Input mode
Open
VSS
0.47
F
CNVSS(memory expansion mode)
HLDA
ALE
XOUT
BCLK
RDY
CNVSS(microprocessor mode)
AVCC
Port P0 to P10
(except for P85)
Input mode
Output mode
NMI
AVCC
AVSS
VREF
Open
VCC
Input mode
Open
0.47
F
CNVSS
XOUT
BYTE
Port P45/CS1
to P47/CS3
Table 1.23.2. Example connection of unused pins in memory expansion mode and microprocessor mode
Table 1.23.1. Example connection of unused pins in single-chip mode
Pin name
Ports P0 to P10 (excluding P85)
(Note 1)
XOUT
(Note 2)
______
NMI
AVCC
AVSS, VREF, BYTE
CNVSS
Connection
After setting for input mode, connect every pin to VSS or VCC via a resistor;
or after setting for output mode, leave these pins open.
Open
Connect via resistor to VCC (pull-up)
Connect to VCC
Connect to VSS
Connect via resistor to VSS (pull-down)
Note 1: In M30623(80-pin package), P1 P44 to P47, P72 to P75, and P91 are not connected to external pin, but exist
inside microcomputer. So set these ports for output mode.
Note 2: With external clock input to XIN pin.
Pin name
Ports P6 to P10 (excluding P85)
(Note 1)
______
P45/CS1 to P47/CS3
_______
_________
BHE, ALE, HLDA, XOUT(Note 2), BCLK
__________
_______
HOLD, RDY, NMI
AVCC
AVSS, VREF
CNVSS
Connection
After setting for input mode, connect every pin to VSS or VCC via a resistor;
or after setting for output mode, leave these pins open.
Sets ports to input mode, sets bits CS1 throuth CS3 to 0, and connects to
VCC via resistors (pull-up).
Open
Connect via resistor to VCC (pull-up)
Connect to VCC
Connect to VSS
Connect via resistor to VSS (pull-down) in the memory expansion mode.
Connect via resistor to VCC (pull-up) in the microprocessor mode.
Note 1: In M30623(80-pin package), P72 to P75, and P91 are not connected to external pin, but exist inside micro-
computer. So set these ports for output mode.
Note 2: With external clock input to XIN pin.
Note 3: The M16C/62T group is not guaranteed to operate in memory expansion and microprocessor modes.
Note 1: In M30623(80-pin package), P1, P44 to P47, P72 to P75, and P91 are not connected to external pin, but
exist inside microcomputer. So set these ports for output mode.
Note 2: With external clock input to XIN pin.
Note 3: The M16C/62T group is not guaranteed to operate in memory expansion and microprocessor modes.