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M451
May. 4, 2018
Page
166
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1006
Rev.2.08
M4
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Group
Pin Name
GPIO
MFP*
Type
Description
(M45xD/M45xC Only)
UART3_TXD
PD.12
MFP3
O
Data transmitter output pin for UART3.
UART3_TXD
PA.8
MFP3
O
Data transmitter output pin for UART3.
UART3_TXD
PB.3
MFP9
O
Data transmitter output pin for UART3.
(M45xD/M45xC Only)
UART3_TXD
PE.10
MFP9
O
Data transmitter output pin for UART3.
(M45xD/M45xC Only)
UART3_TXD
PC.0
MFP9
O
Data transmitter output pin for UART3.
(M45xD/M45xC Only)
UART3_nCTS
PD.14
MFP3
I
Clear to Send input pin for UART3.
UART3_nCTS
PA.10
MFP3
I
Clear to Send input pin for UART3.
UART3_nRTS
PD.15
MFP3
O
Request to Send output pin for UART3.
UART3_nRTS
PA.11
MFP3
O
Request to Send output pin for UART3.
USB
USB_VBUS_EN
PC.4
MFP4
O
USB external VBUS regulator enable pin.
(M45xG/M45xE Only)
USB_VBUS_EN
PA.2
MFP1
O
USB external VBUS regulator enable pin.
(M45xG/M45xE Only)
USB_VBUS_ST
PC.3
MFP4
I
USB external VBUS regulator status pin.
(M45xG/M45xE Only)
USB_VBUS_ST
PA.3
MFP1
I
USB external VBUS regulator status pin.
(M45xG/M45xE Only)
LXT
X32_IN
PF.1
MFP1
I
External 32.768 kHZ (low speed) crystal input
pin.
X32_OUT
PF.0
MFP1
O
External 32.768 kHZ (low speed) crystal output
pin.
HXT
XT1_IN
PF.4
MFP1
I
External 4~20 MHz (high speed) crystal input
pin.
XT1_OUT
PF.3
MFP1
O
External 4~20 MHz (high speed) crystal output
pin.
Table 4-1 M451 GPIO Multi-function Table