141
/
838
Nations Technologies Inc.
Tel
:
+86-755-86309900
:
Address: Nations Tower, #109 Baoshen Road, Hi-tech Park North.
Nanshan District, Shenzhen, 518057, P.R.China
Figure 7-5 High impedance analog mode configuration
7.2.2
Status after reset
During and just after the reset, the alternate functions are not active, and the I/O port is configured to be in analog
mode (PCFGy[1:0]=00b
,
PMODEy[1:0]=00b) by default. But there are several exceptional signals:
BOOT0
、
NRST
、
OSC_IN
、
OSC_OUT has no GPIO function by default
BOOT0 pin default configuration is input pull down
NRST pull up input and output
After the reset, the default state of the pin associated with the debug system is to enable the SWD-JTAG, and
the JTAG pin is placed on the input pull-up or pull-down mode
PA15: JTDI is placed in input pull-up mode
PA14: JTCK is placed in input pull-down mode
PA13: JTMS is placed in input pull-up mode
PB4: NJTRST is placed in input pull-up mode
PB3:JTD0 is placed in the push-pull output without pull-down.
PD0 and PD1:
PD0 and PD1 default to analog mode in 80 and above pin packages.
PD0 and PD1 are multiplexed to OSC_IN/OUT for pin packages with less than 80 pins.