AT32F421
Series Reference Manual
2022.11.11
Page 88
Rev 2.02
GPIOA_PULL
0x0C
0x2400 0000
GPIOx_PULL(x = B,C,F)
0x0C
0x0000 0000
GPIOx_IDT
0x10
0x0000 XXXX
GPIOx_ODT
0x14
0x0000 0000
GPIOx_SCR
0x18
0x0000 0000
GPIOx_WPR
0x1C
0x0000 0000
GPIOx_MUXL
0x20
0x0000 0000
GPIOx_MUXH
0x24
0x0000 0000
GPIOx_CLR
0x28
0x0000 0000
GPIOx_HDRV
0x3C
0x0000 0000
6.3.1
GPIO configuration register (GPIOx_CFGR) (x=A
…H)
Address offset: 0x00
Reset value: 0x28000000 for port A
0x00000000 for other ports
Bit
Register
Reset value
Type
Description
Bit 2y+1: 2y
IOMCy
0x2800 0000 rw
GPIOx mode configuration (y=0~15)
These bits are used to configure the operating modes of
GPIOx:
00: Input mode (after reset)
01: General-purpose output
10: Multiplexed function
11: Analog
6.3.2
GPIO input mode register (GPIOx_OMODE) (x=A
…H)
Bit
Register
Reset value
Type
Description
Bit 31: 16 Reserved
0x0000
resd
Always 0
Bit 15: 0
OM
0x0000
rw
GPIOx output mode configuration (y=0..15)
When GPIOx is used as output, there are two output
modes for selection:
0: Push-pull (reset state)
1: Open-drain
6.3.3
GPIO drive capability register (GPIOx_ODRVR) (x=A..H)
Address offset: 0x08
Reset values: 0x0C00 0000 for port A 0x00000000 for other ports
Bit
Register
Reset value
Type
Description
Bit
2y+1: 2y
ODRVy
0x0000 0000 rw
GPIOx drive capability (y=0…15)
This field is used to configure the IO port drive capability.
x0: Normal sourcing/sinking strength
01: Large sourcing/sinking strength
11: Normal sourcing/sinking strength
6.3.4
GPIO pull-up/pull-down register (GPIOx_PULL) (x=A..H)
Address offset: 0x0C
Reset values: 0x2400 0000 for port A 0x0000000 for other ports
Bit
Register
Reset value
Type
Description
Bit
2y+1: 2y
PULLy
0x6400 0000 rw
GPIOx pull-up/pull-down configuration (y=0…15)
This field is used to configure the pull-up/pull-down of the
IO port.
00: No pull-up, pull-down
01: Pull-up
10: Pull-down