4501_M Datasheet, PDF (128/212 Pages) Renesas Technology Corp – 4-BIT CISC SINGLE-CHIP MICROCOMPUTER 4500 SERIES

4501 Group
APPLICATION
2.1 I/O pins
Table 2.1.8 Connections of unused pins
Pin
Connection
Usage condition
XIN
XOUT
Connect to VSS.
Open.
System operates by the on-chip oscillator. (Note 1)
System operates by the external clock.
(The ceramic resonator is selected with the CMCK instruction.)
System operates by the RC oscillator.
(The RC oscillation is selected with the CRCK instruction.)
System operates by the on-chip oscillator. (Note 1)
D0, D1 Open. (Output latch is set to “1.”)
Open. (Output latch is set to “0.”)
Connect to VSS.
D2/C
D3/K
Open. (Output latch is set to “1.”) The key-on wakeup function is not selected. (Note 4)
Open. (Output latch is set to “0.”) The pull-up function and the key-on wakeup function are not
selected. (Notes 2, 3)
Connect to VSS.
The pull-up function and the key-on wakeup function are not
selected. (Notes 2, 3)
P00–P03 Open. (Output latch is set to “1.”) The key-on wakeup function is not selected. (Note 4)
Open. (Output latch is set to “0.”) The pull-up function and the key-on wakeup function are not
selected. (Notes 2, 3)
Connect to VSS.
The pull-up function and the key-on wakeup function are not
selected. (Notes 2, 3)
P10, P11 Open. (Output latch is set to “1.”) The key-on wakeup function is not selected. (Note 4)
P12/CNTR Open. (Output latch is set to “0.”) The pull-up function and the key-on wakeup function are not
selected. (Notes 2, 3)
Connect to VSS.
The pull-up function and the key-on wakeup function are not
selected. (Notes 2, 3)
P13/INT
Open. (Output latch is set to “1.”) The key-on wakeup function is not selected. The input to INT
pin is disabled. (Notes 4, 5)
Open. (Output latch is set to “0.”) The pull-up function and the key-on wakeup function are not
selected. (Notes 2, 3)
Connect to VSS.
The pull-up function and the key-on wakeup function are not
selected. (Notes 2, 3)
P20/AIN0
P21/AIN1
Open. (Output latch is set to “1.”) The key-on wakeup function is not selected. (Note 4)
Open. (Output latch is set to “0.”) The pull-up function and the key-on wakeup function are not
selected. (Notes 2, 3)
Connect to VSS.
The pull-up function and the key-on wakeup function are not
selected. (Notes 2, 3)
Notes 1: When the ceramic resonator or the RC oscillation is not selected by program, system operates by
the on-chip oscillator (internal oscillator).
2: When the pull-up function is left valid, the supply current is increased. Do not select the pull-up function.
3: When the key-on wakeup function is left valid, the system returns from the RAM back-up state
immediately after going into the RAM back-up state.
Do not select the key-on wakeup function.
4: When selecting the key-on wakeup function, select also the pull-up function.
5: Clear the bit 3 (I13) of register I1 to “0” to disable to input to INT pin (after reset: I13 = “0”)
(Note when connecting to VSS)
q Connect the unused pins to VSS using the thickest wire at the shortest distance against noise.
Rev.2.01 Feb 07, 2005
REJ09B0192-0201
2-11