Difference between revisions of "PWM Generator"

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Pulse wide modulator generator with up to 3 channels.
 
Pulse wide modulator generator with up to 3 channels.
 +
 +
This module uses the avr timers to generate the pwm signals, so for every channel a timer is necessary.
 +
It depends on the hardware and other modules, if three timers are available for the the three channels.
 +
 +
To get background infos you can have a look at this tutorial (in german): [[http://www.mikrocontroller.net/articles/AVR-Tutorial:_PWM AVR-Tutorial: PWM]]
 +
 +
Status: Basic modul works - tested and used 2012-05-25
  
  
 
== Connection ==
 
== Connection ==
  
Every channels needs a port.
+
Every channels requieres a port, but since the timers are used, the ports have a predefined assignment - depending on the mcrocontroller.
 +
 
 +
Nevertheless you have to do some pin definition.
 +
Here the version for the AtMega32:
 +
 
 +
ifdef(`conf_CH_A_PWM_GENERAL', `dnl
 +
  pin(CHANNEL_A_PWM, PD5, OUTPUT)
 +
')
 +
ifdef(`conf_CH_B_PWM_GENERAL', `dnl
 +
  pin(CHANNEL_B_PWM, PD4, OUTPUT)
 +
')
 +
ifdef(`conf_CH_C_PWM_GENERAL', `dnl
 +
  # error 3 Channel pwm unsupported.
 +
')
 +
 
 +
You can also use the script add-hardware (in folder scripts) to generate a board-layout for your current configuration. I don't know the current status of the script - so it is possible, that not every features is supported.
 +
 
 +
== Optional components ==
  
At the moment none of the standard boards has a pin configuration already implemented. It would not make much sense, because you would have to adapt it anyway.
+
=== PWM Wave ===
  
So here a example you can modify and copy to the configuration of the board used:
+
Output of wave files
  
ifdef(`conf_PWM', `dnl
+
=== PWM Melody ===
#ifdef CH_A_PWM_GENERAL_SUPPORT
+
 
  pin(CHANNEL_A_PWM, PC0, OUTPUT)
+
Melody generator
#endif /* CH_A_PWM_GENERAL_SUPPORT */
+
 
#ifdef CH_B_PWM_GENERAL_SUPPORT
+
=== PWM Servo ===
  pin(CHANNEL_B_PWM, PC1, OUTPUT)
+
 
#endif /* CH_B_PWM_GENERAL_SUPPORT */
+
Control a servo motor
#ifdef CH_C_PWM_GENERAL_SUPPORT
 
  pin(CHANNEL_C_PWM, PC2, OUTPUT)
 
#endif /* CH_C_PWM_GENERAL_SUPPORT */
 
')
 

Latest revision as of 17:57, 25 May 2012

PWM Generator
Status
Unstable/Broken
menuconfig I/O->PWM Generator
Pinning yes
Ecmd yes
Depends on ECMD
Requires -
Code https://github.com/ethersex/ethersex/tree/master/hardware/pwm

Pulse wide modulator generator with up to 3 channels.

This module uses the avr timers to generate the pwm signals, so for every channel a timer is necessary. It depends on the hardware and other modules, if three timers are available for the the three channels.

To get background infos you can have a look at this tutorial (in german): [AVR-Tutorial: PWM]

Status: Basic modul works - tested and used 2012-05-25


Connection

Every channels requieres a port, but since the timers are used, the ports have a predefined assignment - depending on the mcrocontroller.

Nevertheless you have to do some pin definition. Here the version for the AtMega32:

ifdef(`conf_CH_A_PWM_GENERAL', `dnl
 pin(CHANNEL_A_PWM, PD5, OUTPUT)
')
ifdef(`conf_CH_B_PWM_GENERAL', `dnl
 pin(CHANNEL_B_PWM, PD4, OUTPUT)
')
ifdef(`conf_CH_C_PWM_GENERAL', `dnl
  # error 3 Channel pwm unsupported.
')

You can also use the script add-hardware (in folder scripts) to generate a board-layout for your current configuration. I don't know the current status of the script - so it is possible, that not every features is supported.

Optional components

PWM Wave

Output of wave files

PWM Melody

Melody generator

PWM Servo

Control a servo motor