Infineon PWM Buzzer 1 User manual

AURIX™ TC2xx Microcontroller Training
V1.0.0
PWM_Buzzer_1
PWM controlled melody on Buzzer
Please read the Important Notice and Warnings at the end of this document

Scope of work
The GTM unit is used to play a PWM-controlled song with a piezo
buzzer.
The generated PWM (Pulse-Width Modulation) signal is controlled by timer
TOM1 of the GTM block. The signal drives the piezo buzzer via the pin 0 of
the port 33.
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2019-10-17 Copyright © Infineon Technologies AG 2019. All rights reserved.

Introduction
›The Generic Timer Module (GTM) is a modular timer unit designed to
accommodate many timer applications.
›The Timer Output Module (TOM), which is part of the GTM, offers sixteen
independent channels to generate output signals.
›The Clock Management Unit (CMU) is responsible for clock generation of
the GTM. The Fixed Clock Generation (FXU), subunit of the CMU,
provides five predefined non-configurable clocks for the TOM
submodules.
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2019-10-17 Copyright © Infineon Technologies AG 2019. All rights reserved.

Hardware setup
This code example has been
developed for the board
KIT_AURIX_TC297_TFT_BC-Step.
The piezo buzzer (1) is used for this
example. 1
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Implementation
Initialization of PWM Buzzer
The initialization of the PWM Buzzer is done once in the setup phase by calling the function
initPWMBuzzer(), which contains the following steps:
›Initialize the time constants by calling the service function initTime() from iLLD header file
Bsp.h
›Enable the GTM by calling the function IfxGtm_enable()
›Enable the FXU clocks by calling the function IfxGtm_Cmu_enableClocks()
›Initialize the timer configuration with default values by calling the function
IfxGtm_Tom_Timer_initConfig()
›Set the timer configuration variable timerCfg with the user defined values
›Initialize the timer through the iLLD function IfxGtm_Tom_Timer_init()
›Enable the GTM TOM channel 4 by calling the iLLD function
IfxGtm_Tom_Tgc_enableChannelsUpdate()
All the functions used for the configuration of the PWM Buzzer are provided by the iLLD header
IfxGtm_Tom_Pwm.h.
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2019-10-17 Copyright © Infineon Technologies AG 2019. All rights reserved.

Implementation
Configuration of the variable timerCfg
Setting of the timerCfg variable is done once in the setup phase in the function
initPWMBuzzer() with the following steps:
›Set TOM1 as the timer for generating the PWM signal
timerCfg.tom = IfxGtm_Tom_1
›Set the channel 4 of TOM1 as the channel used for the timer
timerCfg.timerChannel = IfxGtm_Tom_Ch_4
›Select the clock source
timerCfg.clock = IfxGtm_Tom_Ch_ClkSrc_cmuFxclk2
›Set port and pin for PWM output
timerCfg.triggerOut = &IfxGtm_TOM1_4_TOUT22_P33_0_OUT
›Enable TOM channel
timerCfg.base.trigger.enabled = TRUE
›Enable TOM channel output
timerCfg.base.trigger.outputEnabled = TRUE
›Starting PWM with rising edge
timerCfg.base.trigger.risingEdgeAtPeriod = TRUE
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Implementation
Playing song
The song is played by repeatedly calling the function playTone() for each note, which contains
the following steps:
1. Set the PWM frequency (in Hz) through the iLLD function
IfxGtm_Tom_Timer_setFrequency()
2. Set the volume level by calling the function setVolume(). This is done by setting the PWM
duty cycle with the function IfxGtm_Tom_Timer_setTrigger()
3. Start the timer with the iLLD function IfxGtm_Tom_Timer_run()
4. Wait until the end of the note through the service function waitTime()
5. Stop the timer with the iLLD function IfxGtm_Tom_Timer_stop()
t
PWM signal
Period of PWM
Duty cycle of the PWM
Sound duration
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Run and Test
After code compilation and flashing the device, listen to the Buzzer (1) which
should play the sound from the game Super Mario.
1
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References
›More code examples can be found on the GIT repository:
›https://github.com/Infineon/AURIX_code_examples
›For additional trainings, visit our webpage:
›https://www.infineon.com/aurix-expert-training
›AURIX™ Development Studio is available online:
›https://www.infineon.com/aurixdevelopmentstudio
›Use the „Import...“ function to get access to more code examples.
›For questions and support, use the AURIX™ Forum:
›https://www.infineonforums.com/forums/13-Aurix-Forum
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2019-10-17 Copyright © Infineon Technologies AG 2019. All rights reserved.

IMPORTANT NOTICE
The information given in this document shall in no
event be regarded as a guarantee of conditions or
characteristics (“Beschaffenheitsgarantie”).
With respect to any examples, hints or any typical
values stated herein and/or any information
regarding the application of the product, Infineon
Technologies hereby disclaims any and all
warranties and liabilities of any kind, including
without limitation warranties of non-infringement
of intellectual property rights of any third party.
In addition, any information given in this
document is subject to customer’s compliance
with its obligations stated in this document and
any applicable legal requirements, norms and
standards concerning customer’s products and
any use of the product of Infineon Technologies in
customer’s applications.
The data contained in this document is exclusively
intended for technically trained staff. It is the
responsibility of customer’s technical
departments to evaluate the suitability of the
product for the intended application and the
completeness of the product information given in
this document with respect to such application.
For further information on the product,
technology, delivery terms and conditions and
prices please contact your nearest Infineon
Technologies office (www.infineon.com).
WARNINGS
Due to technical requirements products may
contain dangerous substances. For information
on the types in question please contact your
nearest Infineon Technologies office.
Except as otherwise explicitly approved by
Infineon Technologies in a written document
signed by authorized representatives of Infineon
Technologies, Infineon Technologies’ products
may not be used in any applications where a
failure of the product or any consequences of the
use thereof can reasonably be expected to result
in personal injury.
Edition 2019-10
Published by
Infineon Technologies AG
81726 Munich, Germany
© 2019 Infineon Technologies AG.
All Rights Reserved.
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Document reference
PWM_Buzzer_1
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