wenkong_junshi/Examples/TIMER/TIMER1_singlepulse

/*!
\file readme.txt
\brief description of the TIMER1 single pulse demo for gd32f30x

\version 2017-02-10, V1.0.0, firmware for GD32F30x
\version 2018-10-10, V1.1.0, firmware for GD32F30x
\version 2018-12-25, V2.0.0, firmware for GD32F30x
\version 2020-09-30, V2.1.0, firmware for GD32F30x
*/

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This demo is based on the GD32307C-EVAL-V1.1 board, it shows how to configure
the TIMER1 peripheral in single pulse mode.
The external signal is connected to TIMER1 CH0 pin (PA0) and the falling
edge is used as active edge.

The single pulse signal is output on TIMER1 CH1 pin (PA1).

The TIMER1CLK frequency is set to systemcoreclock,the prescaler is 60,so the
TIMER1 counter clock is 2MHz.

single pulse value = (TIMER1_period - TIMER1_pulse) / TIMER1 counter clock
= (65535 - 11535) / 2MHz = 27 ms.

Connect the TIMER1 CH0 pin (PA0)to KEY2(PC13),When KEY_TAMPER is pressed,
a single pulse is generated.