Rev. 1.10

10 of �5

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��-bit �RM Co�tex™-M� MCU

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I/O Ports

There are up to 32 General Purpose I/O pins, (GPIO), named PA0 ~ PA15 and PB0 ~ PB15 for the

device to implement logic input/output functions. Each of the GPIO ports has related control and

configuration registers to satisfy the requirements of specific applications.

The GPIO ports are pin-shared with other alternative functions (AFs) to obtain maximum flexibility

on the package pins. The GPIO pins can be used as alternative functional pins by configuring the

corresponding registers regardless of the AF input or output pins.

The external interrupts on the GPIO pins of the device have related control and configuration

registers in the External Interrupt Control Unit (EXTI).

PWM Generation and Capture Timers

The General-Purpose Timers, known as GPTM0 and GPTM1, consist of one 16-bit

up/down-counter, four 16-bit Capture/Compare Registers (CCRs), one 16-bit Counter-Reload

Register (CRR) and several control/status registers. They can be used for a variety of purposes

including general time, input signal pulse width measurement or output waveform generation

such as single pulse generation or PWM output. The GPTM supports an Encoder Interface using a

decoder with two inputs.