CHAPTER 2 PIN FUNCTIONS
Preliminary User’s Manual U19014EJ1V0UD
27
2.3 Pin I/O Circuits and Recommended Connection of Unused Pins
Table 2-2 shows the types of pin I/O circuits and the recommended connections of unused pins.
See
Figure 2-1
for the configuration of the I/O circuit of each type.
Table 2-2. Pin I/O Circuit Types
Pin Name
I/O Circuit Type
I/O
Recommended Connection of Unused Pins
P00/TI000
P01/TI010/TO00
P10/SCK10
P11/SI10
5-AH
P12/SO10
P13/TxD6
5-AG
P14/RxD6 5-AH
P15
P16/TOH1
5-AG
P17/TI50/TO50
P30/INTP1
P31/INTP2/OCD1A
Note 1
P32/INTP3/OCD1B
P33/TI51/TO51
5-AH
Input:
Independently connect to EV
DD
or EV
SS
via a resistor.
Output: Leave
open.
P60
P61
13-AD
Input:
Connect to EV
SS
.
Output: Leave this pin open at low-level output after clearing
the output latch of the port to 0.
P121/X1/OCD0A
Note 2, 3
P122/X2/EXCLK/OCD0B
Note 3
37
Input:
Independently connect to V
DD
or V
SS
via a resistor.
Output: Leave
open.
USBM 24-A
USBP 24-A
I/O
Connect to EV
SS
.
USBPUC 3-C
Output
Leave
open.
FLMD0 38
−
Connect to EV
SS
or V
SS
.
Note 4
RESET
2
Input
Connect directly to V
DD
or via a resistor.
Notes 1.
When writing the flash memory with a flash memory programmer, connect P31/INTP2/OCD1A as follows.
•
P31/INTP2/OCD1A: Connect to EV
SS
via a resistor (10 k
Ω
: recommended).
The above connection is not necessary when writing the flash memory by means of self programming.
2.
When writing the flash memory with a flash memory programmer, connect P121/X1/OCD0A as follows.
•
P121/X1/OCD0A: When using this pin as a port, connect it to V
SS
via a resistor (10 k
Ω
: recommended) (in
the input mode) or leave it open (in the output mode).
The above connection is not necessary when writing the flash memory by means of self programming.
3.
Use recommended connection above in I/O port mode (see
Figure 5-2 Format of Clock Operation Mode
Select Register (OSCCTL)
) when these pins are not used.
4.
FLMD0 is a pin that is used to write data to the flash memory. To rewrite the data of the flash memory on-
board, connect this pin to V
SS
via a resistor (10 k
Ω
: recommended).
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