RL78/G13 CHAPTER 4 PORT FUNCTIONS
R01UH0146EJ0100 Rev.1.00 241
Sep 22, 2011
4.2.15 Port 14
Port 14 is an I/O port with an output latch. Port 14 can be set to the input mode or output mode in 1-bit units using port
mode register 14 (PM14). When the P140 to P147 pins are used as an input port, use of an on-chip pull-up resistor can
be specified in 1-bit units by pull-up resistor option register 14 (PU14).
Input to the P142 and P143 pins can be specified through a normal input buffer or a TTL input buffer in 1-bit units using
port input mode register 14 (PIM14).
Output from the P142 to P144 pins can be specified as N-ch open-drain output (V
DD tolerance) in 1-bit units using port
output mode register 14 (POM14).
Input to the P147 pin can be specified as analog input or digital input in 1-bit units, using port mode control register 14
(PMC14).
This port can also be used for clock/buzzer output, external interrupt request input, and A/D converter analog input.
Reset signal generation sets P140 to P146 to input mode, and sets P147 to analog input.
Table 4-18. Settings of Registers When Using Port 14
Pin Name
Name I/O
PM14× PIM14× POM14× PMC14× Alternate Function Setting Remark
Input 1
− − − ×
P140,
P141
Output 0
PCLBUZ0 output,
PCLBUZ1 output = 0
Note 1
1 0
× − ×
CMOS input Input
1 1
×
×
TTL input
0
×
0 CMOS output
P142,
P143
Output
0
×
1
SCK30/SCL30 output = 1,
SDA30 output = 1
Note 2
N-ch O.D. output
Input 1
− × − ×
0 0 CMOS output
P144
Output
0 1
SO30/TxD3 output = 1
Note 2
N-ch O.D. output
Input 1
− − − ×
P145
Output 0
TO07 output = 0
Note 3
Input 1
− − − ×
P146
Output 0
×
Input 1
− −
0
×
P147
Output 0 0
×
Notes 1. To use P140/PCLBUZ0/INTP6 or P141/PCLBUZ1/INTP7 as a general-purpose port, set bit 7 of clock
output select registers 0 and 1 (CKS0, CKS1) to “0”, which is the same as their default status settings.
2. To use P142/SCK30/SCL30, P143/SI30/RxD3/SDA30, or P144/SO30/TxD3 as a general-purpose port, set
serial channel enable status register 1 (SE1), serial output register 1 (SO1) and serial output enable
register 1 (SOE1) to the default status.
3. To use P145/TI07/TO07 as a general-purpose port, set bit 7 (TO07) of timer output register 0 (TO0) and bit
7 (TOE07) of timer output enable register 0 (TOE0) to “0”, which is the same as their default status setting.
Remark ×: don’t care
PM14×: Port mode register 14
PIM14×: Port input mode register 14
POM14×: Port output mode register 14
PMC14×: Port mode control register 14
<R>
<R>
<R>
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