Analog Input Configuration; Figure 17. Alternate Function Configuration; Figure 18. High Impedance-Analog Input Configuration - ST STM32F101xx Reference Manual

RM0034

Figure 17. Alternate function configuration

To on-chip
peripheral
Read
Write
Read/write
From on-chip
peripheral
1. V
DD_FT
8.1.10

Analog input configuration

When the I/O Port is programmed as Analog Input Configuration:
●
The Output Buffer is disabled.
●
The Schmitt Trigger Input is de-activated providing zero consumption for every analog
value of the I/O pin. The output of the Schmitt Trigger is forced to a constant value (0).
●
The weak pull-up and pull-down resistors are disabled.
● Read access to the Input Data Register gets the value "0".
The Figure 18 on page 143
I/O Port bit.

Figure 18. High impedance-analog input configuration

To on-chip
peripheral
Read
Write
Read/write
From on-chip
peripheral
General-purpose and alternate-function I/Os (GPIOs and AFIOs)
Alternate Function Input
Alternate Function Output
is a potential specific to five-volt tolerant I/Os and different from V
shows the High impedance-Analog Input Configuration of the
Analog Input
on
TTL Schmitt
trigger
Input driver
Output driver
Output
control
off
0
TTL Schmitt
trigger
Input driver
V
DD
P-MOS
N-MOS
push-pull or
V
SS
open-drain
.
DD
V
V
(1)
V
or V
DD DD_FT
Protection
diode
I/O pin
Protection
diode
VSS
ai14785
(1)
or V
DD DD_FT
Protection
diode
I/O pin
Protection
diode
SS
ai14786
143/959