Digi
/
dey-examples
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
dey-examples/apix-pwm-example/README.md

3.4 KiB
Raw Blame History

Digi APIX PWM Example Application

Example application to access and manage PWM lines using the Digi APIX library.

This application enables one PWM line of the board using a frequency of 1000Hz. Then, it progressively modifies the duty cycle in a loop from 10% to 90% and vice-versa.

The PWM lines used in this example are mapped as follows in the Digi boards:

  • ConnectCore MP25 DVK: MikroBus PWM channel 4 - PIN 1 of the MikroBus connector (J40).
  • ConnectCore MP13 DVK: MikroBus PWM channel 8 - PIN 1 of the MikroBus connector (J31). Need to add the overlay _ov_board_pwm8_ccmp13-dvk.dtbo
  • ConnectCore MP15 DVK: MikroBus PWM channel 4 - PIN 1 of the MikroBus connector (J31).
  • ConnectCore 93 DVK: PWM0 channel 1 shared with LVDS backlight. Need to disable LVDS and enable the PWM channel in the DTB.
  • ConnectCore 91 DVK: PWM0 channel 1 shared.
  • ConnectCore 8M Mini DVK: MCA PWM0 channel 2 connected to the LED1.
  • ConnectCore 8M Nano DVK: MCA PWM0 channel 2 connected to the LED1.
  • ConnectCore 8X SBC Pro: MCA PWM2 channel 0 - Pin A3 of the Expansion connector (J20).
  • ConnectCore 8X SBC Express: MCA PWM1 channel 0 - Pin 33 of the Raspberry Pi Expansion connector (J11).
  • ConnectCore 6UL SBC Pro: PWM4 - Pin 11 of the GPIO connector (J30).
  • ConnectCore 6UL SBC Express: PWM1 - Pin 27 of the expansion connector (J8).
  • ConnectCore 6 Plus SBC: PWM1 - Pin 10 of the parallel video (LCD) connector (J21).
  • ConnectCore 6 SBC: PWM1 - Pin 10 of the parallel video (LCD) connector (J21).

Running the application

Once the binary is in the target, launch the application:

~# ./apix-pwm-example
Example application using libdigiapix PWM support

Usage: apix-pwm-example <pwm-chip> <pwm-freq>

<pwm-chip>       PWM chip number or alias
<pwm-channel>    PWM channel number or alias
<pwm-freq>       Frequency to use (Hz)

Aliases for PWM can be configured in the library config file

If no arguments are provided, the example will use the default values:

  • For the interfaces, default values are configured in /etc/libdigiapix.conf.
  • Specific application default values are defined in the main file.

Compiling the application

This demo can be compiled using a Digi Embedded Yocto based toolchain. Make sure to source the corresponding toolchain of the platform you are using, for example, for ConnectCore 6UL:

~$ . <DEY-toolchain-path>/environment-setup-cortexa7t2hf-neon-dey-linux-gnueabi
~$ make

For more information, see the Digi Embedded Yocto online documentation.

License

Copyright 2017-2023, Digi International Inc.

Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.