STM32F100x4, STM32F100x6, STM32F100x8, STM32F100xB
Description
2.21
GPIOs (general-purpose inputs/outputs)
Each of the GPIO pins can be configured by software as output (push-pull or open-drain), as
input (with or without pull-up or pull-down) or as peripheral alternate function. Most of the
GPIO pins are shared with digital or analog alternate functions. All GPIOs are high current-
capable except for analog inputs.
The I/Os alternate function configuration can be locked if needed following a specific
sequence in order to avoid spurious writing to the I/Os registers.
2.22
Remap capability
This feature allows the use of a maximum number of peripherals in a given application.
Indeed, alternate functions are available not only on the default pins but also on other
specific pins onto which they are remappable. This has the advantage of making board
design and port usage much more flexible.
For details refer to Table 4: STM32F100xx pin definitions; it shows the list of remappable
alternate functions and the pins onto which they can be remapped. See the STM32F10xxx
reference manual for software considerations.
2.23
2.24
ADC (analog-to-digital converter)
The 12-bit analog to digital converter has up to 16 external channels and performs
conversions in single-shot or scan modes. In scan mode, automatic conversion is performed
on a selected group of analog inputs.
The ADC can be served by the DMA controller.
An analog watchdog feature allows very precise monitoring of the converted voltage of one,
some or all selected channels. An interrupt is generated when the converted voltage is
outside the programmed thresholds.
DAC (digital-to-analog converter)
The two 12-bit buffered DAC channels can be used to convert two digital signals into two
analog voltage signal outputs. The chosen design structure is composed of integrated
resistor strings and an amplifier in noninverting configuration.
This dual digital Interface supports the following features:
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two DAC converters: one for each output channel
up to 10-bit output
left or right data alignment in 12-bit mode
synchronized update capability
noise-wave generation
triangular-wave generation
dual DAC channels’ independent or simultaneous conversions
DMA capability for each channel
external triggers for conversion
input voltage reference V
REF+
Doc ID 16455 Rev 2
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STMICROELECTRONICS [ ST ]
