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AT32F413
Series Reference Manual
2022.06.27
Page 89
Rev 2.00
7
Multiplexed function I/Os (IOMUX)
7.1 Introduction
AT32F413 support up to 55 bi-directional I/O pins, which are grouped as five categories, namely PA, PB,
PC, PD and PF. Each of the GPIO group provides up to 16 I/O pins that feature communication, control
and data collection. In addition, their main features also include:
Supports general-purpose I/O (GPIO) or multiplex I/O (IOMUX), which will be detailed in this chapter.
Can be configured as multiplex function input/output ports by setting GPIOx_CFGLR or
GPIOx_CFGHR
Most pins support output map for several peripherals. Select different peripheral input/output
through IOMUX register
Supports external interrupt
7.2 Function overview
7.2.1
IOMUX structure
While being used as multiplexed function input, the I/O port should be configured as input modes (floating,
pull-up and pull-down input)
To enable multiplexed function output, the port is configured as multiplexed function output mode (push-
pull or open-drain) by setting GPIOx_CFGLR or GPIOx_CFGHR register. In this case, the pins are
disconnected from GPIO controller, and controlled by IOMUX controller, instead.
To
achieve bidirectional multiplexed function, the port needs to be configured as multiplexed function
output modes (push-pull or open-drain), controlled by IOMUX controller.
In MUX output mode, it is possible that an I/O pin is used as output
for several peripherals. Select the
required multiplexed function output by setting IOMUX registers. However, when a pin is programmed
as MUX IO without activating the corresponding peripheral , its output will not specified.
Figure 7-1
Basic structure of IOMUX basic structure
IO
ESD
protect
SMT trigger
PU
PD
output data
output enable
input enable
input data
push/pull
strength control
analog input/output
A
H
B
b
u
s
IO
M
U
X
c
o
n
tr
o
l
Single IO
Analog
module
Peripheral
Module