Running the demonstrations

STR91x demonstration software

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Note:

When an alarm is occurred the Alarm wave is played.

2.4.2

Wave player

The STR91x microcontroller has several embedded Timers which can be used for timing

purposes and generating the output signals. In this case, we use 2 Timers (TIM) the first

Timer TIM3 is configured to generate a PWM signal with a tunable duty cycle. The second

Timer TIM0 is used to generate an Update interrupt every 45.35 µs (22.05 KHz) which

correspond to the TIM3 Duty cycle update.

The wave file has the following characteristics:

●

*.wav file

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Audio Format: PCM

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Sample rate: 22050 Hz

●

Bits Per Sample: 8 bits

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Number Of Channels: Mono

There is one wave to play:

●

OSIRIS

The following message is displayed on the LCD:

You can re-play a wave only by selecting "Play/Replay". The following message is displayed

on the LCD:

If "SEL" pressed, The following message is displayed on the LCD:

To stop playing press "SEL" or wait until the end of the wave and the MCU will stop it

automatically.

2.4.3

USB mouse demo

The STR91x microcontroller provides an USB (Universal Serial Bus) which provide an

interface between a full-speed USB bus and the AHB bus.

OSIRIS

Wave Player

OSIRIS

Play/Replay

STOP

OSIRIS