- Important Note for Arduino IDE
- Why do we need this ATtiny_PWM library
- Changelog
- Prerequisites
- Installation
- More useful Information
- Usage
- Examples
- Example PWM_Multi
- Debug Terminal Output Samples
- Debug
- Troubleshooting
- Issues
- TO DO
- DONE
- Contributions and Thanks
- Contributing
- License
- Copyright
With some Arduino IDE versions, such as v1.8.19, upload directly via USB to some boards, such as AVR_CuriosityNano3217
can't be done without unknown-to-me
fix. We'll get the following error when uploading
avrdude: Version 6.3-20201216
Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
Copyright (c) 2007-2014 Joerg Wunsch
System wide configuration file is "/home/kh/.arduino15/packages/megaTinyCore/hardware/megaavr/2.5.11/avrdude.conf"
User configuration file is "/home/kh/.avrduderc"
User configuration file does not exist or is not a regular file, skipping
Using Port : usb
Using Programmer : curiosity_updi
avrdude: usbdev_open(): Found nEDBG CMSIS-DAP, serno: MCHP3333021800000998
avrdude: usbdev_open(): WARNING: failed to set configuration 1: Device or resource busy
avrdude: Found CMSIS-DAP compliant device, using EDBG protocol
avrdude: usbdev_send(): wrote -5 out of 912 bytes, err = Input/output error
avrdude: jtag3_edbg_prepare(): failed to send command to serial port
avrdude done. Thank you.
the selected serial port
does not exist or your board is not connected
We can use drag-and-drop method to drag-and-drop
the compiled hex file to CURIOSITY
virtual drive.
If success
, The LED blinks slowly for 2 sec, or rapidly for 2 sec if failure
For example, to run Change_Interval example, use Arduino IDE to compile, and get the Change_Interval.ino.hex
file. For Ubuntu Linux, the file is stored in directory /tmp/arduino_build_xxxxxx
After drag-and-drop the Change_Interval.ino.hex
into CURIOSITY
virtual drive, the code will run immediately if successfully loaded (LED blinks slowly)
Why do we need this ATtiny_PWM library
This hardware-based PWM library, a wrapper and enhancement around megaTinyCore analogWrite()
code, enables you to use Hardware-PWM on Arduino AVR ATtiny-based boards (ATtiny3217, etc.) using megaTinyCore, to create and output PWM. These purely hardware-based PWM channels can generate very high PWM frequencies, depending on CPU clock and acceptable accuracy. The maximum and default resolution is 8-bit resolution.
This library is using the same or similar functions as other FastPWM libraries, as follows, to enable you to port your PWM code easily between platforms
- RP2040_PWM
- AVR_PWM
- megaAVR_PWM
- ESP32_FastPWM
- SAMD_PWM
- SAMDUE_PWM
- nRF52_PWM
- Teensy_PWM
- ATtiny_PWM
- Dx_PWM
- Portenta_H7_PWM
- MBED_RP2040_PWM
- nRF52_MBED_PWM
- STM32_PWM
The most important feature is they're purely hardware-based PWM channels. Therefore, their operations are not blocked by bad-behaving software functions / tasks.
This important feature is absolutely necessary for mission-critical tasks. These hardware PWM-channels, still work even if other software functions are blocking. Moreover, they are much more precise (certainly depending on clock frequency accuracy) than other software timers using millis()
or micros()
. That's necessary if you need to control external systems (Servo, etc.) requiring better accuracy.
New efficient setPWM_manual()
function enables waveform creation using PWM.
The PWM_Multi example will demonstrate the usage of multichannel PWM using multiple Hardware-PWM blocks (Timer & Channel). The 2 independent Hardware-PWM channels are used to control 2 different PWM outputs, with totally independent frequencies and dutycycles on ATtiny-based boards
.
Being hardware-based PWM, their executions are not blocked by bad-behaving functions / tasks, such as connecting to WiFi, Internet or Blynk services.
This non-being-blocked important feature is absolutely necessary for mission-critical tasks.
Imagine you have a system with a mission-critical function, controlling a robot or doing something much more important. You normally use a software timer to poll, or even place the function in loop()
. But what if another function is blocking the loop()
or setup()
.
So your function might not be executed, and the result would be disastrous.
You'd prefer to have your function called, no matter what happening with other functions (busy loop, bug, etc.).
The correct choice is to use hardware-based PWM
.
These hardware-based PWM channels still work even if other software functions are blocking. Moreover, they are much more precise (certainly depending on clock frequency accuracy) than other software-based PWMs, using millis()
or micros()
.
Functions using normal software-based PWMs, relying on loop()
and calling millis()
, won't work if the loop()
or setup()
is blocked by certain operation. For example, certain function is blocking while it's connecting to WiFi or some services.
- tinyAVR boards using megaTinyCore
Arduino IDE 1.8.19+
for Arduino.SpenceKonde megaTinyCore core 2.6.4+
for Arduino ATtiny boards. . Follow megaTinyCore Installation.
The best and easiest way is to use Arduino Library Manager
. Search for ATtiny_PWM, then select / install the latest version.
You can also use this link for more detailed instructions.
Another way to install is to:
- Navigate to ATtiny_PWM page.
- Download the latest release
ATtiny_PWM-main.zip
. - Extract the zip file to
ATtiny_PWM-main
directory - Copy whole
ATtiny_PWM-main
folder to Arduino libraries' directory such as~/Arduino/libraries/
.
- Install VS Code
- Install PlatformIO
- Install ATtiny_PWM library by using Library Manager. Search for ATtiny_PWM in Platform.io Author's Libraries
- Use included platformio.ini file from examples to ensure that all dependent libraries will installed automatically. Please visit documentation for the other options and examples at Project Configuration File
- Arduino 101: Timers and Interrupts
- Getting Started with Timer/Counter Type B (TCB)
- megaTinyCore README.md
- ATtiny3217 Curiosity Nano Hardware User Guide
- AVR128DA48-Curiosity-Nano-Hardware-User Guide
- AVR128DB48-Curiosity-Nano-Hardware-User Guide
TCB0-TCB1 are 16-bit timers
The ATtiny boards, such as ATtiny3217
, ATtiny1617
, will have only maximum 2 TCB timers, (TCB0-TCB1).
The ATtiny boards, such as ATtiny817
, will have only maximum 1 TCB timer, (TCB0).
The number of TCB timers will be automatically configured by the library.
The following is the partial list of number of TCBs for each ATtiny board/chip
ATtiny3217, ATtiny1617, ATtiny3216, ATtiny1616, ATtiny1614
ATtinyx12, ATtinyx14, ATtinyx16, ATtinyx17, such as ATtiny817, ATtiny417, ATtiny816, etc.
ATtinyx02, ATtinyx04, ATtinyx06, ATtinyx07, such as ATtiny1607, ATtiny807, ATtiny1606, etc.
Before using any PWM Timer
and channel
, you have to make sure the Timer
and channel
has not been used by any other purpose.
ATtiny_PWM* PWM_Instance;
PWM_Instance = new ATtiny_PWM(pinToUse, frequency, dutyCycle, channel, PWM_resolution);
if (PWM_Instance)
{
PWM_Instance->setPWM();
}
To use float new_dutyCycle
PWM_Instance->setPWM(PWM_Pins, new_frequency, new_dutyCycle);
such as
dutyCycle = 10.0f;
Serial.print(F("Change PWM DutyCycle to ")); Serial.println(dutyCycle);
PWM_Instance->setPWM(pinToUse, frequency, dutyCycle);
To use uint32_t new_dutyCycle
= (real_dutyCycle * 65536) / 100
PWM_Instance->setPWM_Int(PWM_Pins, new_frequency, new_dutyCycle);
such as for real_dutyCycle = 50%
// 50% dutyCycle = (real_dutyCycle * 65536) / 100
dutyCycle = 32768;
Serial.print(F("Change PWM DutyCycle to (%) "));
Serial.println((float) dutyCycle * 100 / 65536);
PWM_Instance->setPWM_Int(pinToUse, frequency, dutyCycle);
for real_dutyCycle = 50%
// 20% dutyCycle = (real_dutyCycle * 65536) / 100
dutyCycle = 13107;
Serial.print(F("Change PWM DutyCycle to (%) "));
Serial.println((float) dutyCycle * 100 / 65536);
PWM_Instance->setPWM_Int(pinToUse, frequency, dutyCycle);
Function prototype
bool setPWM_manual(const uint8_t& pin, const uint16_t& DCValue);
bool setPWM_DCPercentage_manual(const uint8_t& pin, const float& DCPercentage);
bool setPWM_DCPercentageInt_manual(const uint8_t& pin, const uint16_t& DCPercentage);
Need to call only once for each pin
PWM_Instance->setPWM(PWM_Pins, frequency, dutyCycle);
after that, if just changing dutyCycle
/ level
, use the faster
// For 50.0f dutycycle
// 97465ns
new_level = 50.0f * PWM_Instance->getPWMPeriod() / 100.0f ;
PWM_Instance->setPWM_manual(PWM_Pins, new_level);
or better and much easier to use, but slowest
// v1.2.0: 129500ns. Previous v1.1.0 : 169577ns
new_DCPercentage = 50.0f;
PWM_Instance->setPWM_DCPercentage_manual(PWM_Pins, new_DCPercentage);
or the fastest
// dutycyclePercent = 0-65535 == 0-100%
// Faster, 94197ns
dutycyclePercentInt = MAX_16BIT / 2; // 50%
PWM_Instance->setPWM_DCPercentageInt_manual(pinToUse, dutycyclePercentInt);
- PWM_Basic
- PWM_DynamicDutyCycle
- PWM_DynamicDutyCycle_Int
- PWM_DynamicFreq
- PWM_Multi
- PWM_MultiChannel
- PWM_Waveform
- PWM_StepperControl New
- PWM_manual New
- PWM_SpeedTest New
Example PWM_Multi
ATtiny_PWM/examples/PWM_Multi/PWM_Multi.ino
Lines 11 to 141 in 5e2c807
The following is the sample terminal output when running example PWM_DynamicDutyCycle on AVR_ATtiny3217, to demonstrate the ability to provide high PWM frequencies and ability to change DutyCycle on-the-fly
Starting PWM_DynamicDutyCycle on AVR_ATtiny3217
ATtiny_PWM v1.2.0
[PWM] ATtiny_PWM: freq = 5000.00
[PWM] ATtiny_PWM: _dutycycle = 0
=====================================================================================
Change PWM DutyCycle to 90.00
[PWM] setPWM: _dutycycle = 58982 , frequency = 5000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 200 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 62 , _actualFrequency = 5040
[PWM] setPWM_Int: TIMERA0, _dutycycle = 58982 , dutycycle = 56
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 56 , actual DC% = 90.48
=====================================================================================
Actual data: pin = 1, PWM DC = 90.00, PWMPeriod = 200.00, PWM Freq (Hz) = 5000.0000
=====================================================================================
Change PWM DutyCycle to 20.00
[PWM] setPWM: _dutycycle = 13107 , frequency = 5000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 200 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 62 , _actualFrequency = 5040
[PWM] setPWM_Int: TIMERA0, _dutycycle = 13107 , dutycycle = 12
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 12 , actual DC% = 20.63
=====================================================================================
Actual data: pin = 1, PWM DC = 20.00, PWMPeriod = 200.00, PWM Freq (Hz) = 5000.0000
=====================================================================================
Change PWM DutyCycle to 90.00
[PWM] setPWM: _dutycycle = 58982 , frequency = 5000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 200 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 62 , _actualFrequency = 5040
[PWM] setPWM_Int: TIMERA0, _dutycycle = 58982 , dutycycle = 56
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 56 , actual DC% = 90.48
=====================================================================================
Actual data: pin = 1, PWM DC = 90.00, PWMPeriod = 200.00, PWM Freq (Hz) = 5000.0000
=====================================================================================
The following is the sample terminal output when running example PWM_Multi on TAVR_ATtiny3217, to demonstrate the ability to provide high PWM frequencies on multiple PWM-capable
pins
Starting PWM_Multi on AVR_ATtiny3217
ATtiny_PWM v1.2.0
[PWM] ATtiny_PWM: freq = 2000.00 , _dutycycle = 19660
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 500 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 156 , _actualFrequency = 2003
[PWM] setPWM_Int: TCA0 pin = 0 dutycycle = 47 , actual DC% = 30.57
[PWM] ATtiny_PWM: freq = 8000.00 , _dutycycle = 58981
[PWM] setPWM_Int: TIMERD0, _dutycycle = 58981 , dutycycle = 229
[PWM] setPWM_Int 3: TCD0 pin = 12 dutycycle = 229
=====================================================================================
Index Pin PWM_freq DutyCycle Actual Freq
=====================================================================================
0 0 2000.00 30.00 2000.0000
1 12 8000.00 90.00 8000.0000
=====================================================================================
Actual data: pin = 0, PWM DC = 30.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=====================================================================================
=====================================================================================
Actual data: pin = 12, PWM DC = 90.00, PWMPeriod = 125.00, PWM Freq (Hz) = 8000.0000
=====================================================================================
The following is the sample terminal output when running example PWM_DynamicFreq on AVR_ATtiny3217, to demonstrate the ability to change dynamically PWM frequencies
Starting PWM_DynamicFreq on AVR_ATtiny3217
ATtiny_PWM v1.2.0
[PWM] ATtiny_PWM: freq = 10000.00
[PWM] ATtiny_PWM: _dutycycle = 32767
=====================================================================================
Change PWM Freq to 20000.00
[PWM] setPWM: _dutycycle = 32768 , frequency = 20000.00
[PWM] setPWM_Int: new freq = 20000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 50 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 15 , _actualFrequency = 20833
[PWM] setPWM_Int: TIMERA0, _dutycycle = 32768 , dutycycle = 8
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 8 , actual DC% = 56.25
=====================================================================================
Actual data: pin = 1, PWM DC = 50.00, PWMPeriod = 50.00, PWM Freq (Hz) = 20000.0000
=====================================================================================
Change PWM Freq to 10000.00
[PWM] setPWM: _dutycycle = 32768 , frequency = 10000.00
[PWM] setPWM_Int: new freq = 10000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 100 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 31 , _actualFrequency = 10080
[PWM] setPWM_Int: TIMERA0, _dutycycle = 32768 , dutycycle = 16
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 16 , actual DC% = 53.13
=====================================================================================
Actual data: pin = 1, PWM DC = 50.00, PWMPeriod = 100.00, PWM Freq (Hz) = 10000.0000
=====================================================================================
Change PWM Freq to 20000.00
[PWM] setPWM: _dutycycle = 32768 , frequency = 20000.00
[PWM] setPWM_Int: new freq = 20000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 50 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 15 , _actualFrequency = 20833
[PWM] setPWM_Int: TIMERA0, _dutycycle = 32768 , dutycycle = 8
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 8 , actual DC% = 56.25
=====================================================================================
Actual data: pin = 1, PWM DC = 50.00, PWMPeriod = 50.00, PWM Freq (Hz) = 20000.0000
=====================================================================================
The following is the sample terminal output when running example PWM_Waveform on AVR_ATtiny3217, to demonstrate how to use the setPWM_manual()
function in wafeform creation
Starting PWM_Waveform on AVR_ATtiny3217
ATtiny_PWM v1.2.0
============================================================================================
Actual data: pin = 1, PWM DutyCycle = 0.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
============================================================================================
[PWM] setPWM_manual: _dutycycle = 0 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 3276 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 6553 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 9830 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 13107 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 16383 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 19660 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 22937 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 26214 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 29490 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 32767 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 36044 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 39321 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 42597 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 45874 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 49151 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 52428 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 55704 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 58981 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 62258 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 65535 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 62258 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 58981 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 55704 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 52428 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 49151 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 45874 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 42597 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 39321 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 36044 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 32767 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 29490 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 26214 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 22937 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 19660 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 16383 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 13107 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 9830 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 6553 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 3276 , frequency = 2000.00
[PWM] setPWM_manual: _dutycycle = 0 , frequency = 2000.00
The following is the sample terminal output when running example PWM_manual on AVR_ATtiny3217, to demonstrate how to use the setPWM_manual()
and setPWM_DCPercentage_manual()
functions in wafeform creation
Starting PWM_manual on AVR_ATtiny3217
ATtiny_PWM v1.2.0
[PWM] ATtiny_PWM: freq = 2000.00 , _dutycycle = 0
[PWM] setPWM: _dutycycle = 0 , frequency = 2000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 500 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 156 , _actualFrequency = 2003
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 0 , actual DC% = 0.64
=================================================================================================
Actual data: pin = 1, PWM DutyCycle % = 0.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=================================================================================================
[PWM] setPWM_DCPercentage_manual: DCPercentage = 0.00 , dc = 0.00
[PWM] setPWM_manual: _dutycycle = 0 , frequency = 2000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 500 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 156 , _actualFrequency = 2003
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 0 , actual DC% = 0.64
=================================================================================================
Actual data: pin = 1, PWM DutyCycle % = 0.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=================================================================================================
[PWM] setPWM_DCPercentage_manual: DCPercentage = 5.00 , dc = 3276.75
[PWM] setPWM_manual: _dutycycle = 3276 , frequency = 2000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 500 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 156 , _actualFrequency = 2003
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 7 , actual DC% = 5.10
=================================================================================================
Actual data: pin = 1, PWM DutyCycle % = 5.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=================================================================================================
[PWM] setPWM_DCPercentage_manual: DCPercentage = 10.00 , dc = 6553.50
[PWM] setPWM_manual: _dutycycle = 6553 , frequency = 2000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 500 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 156 , _actualFrequency = 2003
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 15 , actual DC% = 10.19
=================================================================================================
Actual data: pin = 1, PWM DutyCycle % = 10.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=================================================================================================
[PWM] setPWM_DCPercentage_manual: DCPercentage = 15.00 , dc = 9830.25
[PWM] setPWM_manual: _dutycycle = 9830 , frequency = 2000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 500 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 156 , _actualFrequency = 2003
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 23 , actual DC% = 15.29
=================================================================================================
Actual data: pin = 1, PWM DutyCycle % = 15.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=================================================================================================
[PWM] setPWM_DCPercentage_manual: DCPercentage = 20.00 , dc = 13107.00
[PWM] setPWM_manual: _dutycycle = 13107 , frequency = 2000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 500 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 156 , _actualFrequency = 2003
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 31 , actual DC% = 20.38
=================================================================================================
Actual data: pin = 1, PWM DutyCycle % = 20.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=================================================================================================
[PWM] setPWM_DCPercentage_manual: DCPercentage = 25.00 , dc = 16383.75
[PWM] setPWM_manual: _dutycycle = 16383 , frequency = 2000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 500 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 156 , _actualFrequency = 2003
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 39 , actual DC% = 25.48
=================================================================================================
Actual data: pin = 1, PWM DutyCycle % = 25.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=================================================================================================
[PWM] setPWM_DCPercentage_manual: DCPercentage = 30.00 , dc = 19660.50
[PWM] setPWM_manual: _dutycycle = 19660 , frequency = 2000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 500 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 156 , _actualFrequency = 2003
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 47 , actual DC% = 30.57
=================================================================================================
Actual data: pin = 1, PWM DutyCycle % = 30.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=================================================================================================
[PWM] setPWM_DCPercentage_manual: DCPercentage = 35.00 , dc = 22937.25
[PWM] setPWM_manual: _dutycycle = 22937 , frequency = 2000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 500 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 156 , _actualFrequency = 2003
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 55 , actual DC% = 35.67
=================================================================================================
Actual data: pin = 1, PWM DutyCycle % = 35.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=================================================================================================
[PWM] setPWM_DCPercentage_manual: DCPercentage = 40.00 , dc = 26214.00
[PWM] setPWM_manual: _dutycycle = 26214 , frequency = 2000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 500 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 156 , _actualFrequency = 2003
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 63 , actual DC% = 40.76
=================================================================================================
Actual data: pin = 1, PWM DutyCycle % = 40.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=================================================================================================
[PWM] setPWM_DCPercentage_manual: DCPercentage = 45.00 , dc = 29490.75
[PWM] setPWM_manual: _dutycycle = 29490 , frequency = 2000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 500 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 156 , _actualFrequency = 2003
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 70 , actual DC% = 45.22
=================================================================================================
Actual data: pin = 1, PWM DutyCycle % = 45.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=================================================================================================
[PWM] setPWM_DCPercentage_manual: DCPercentage = 50.00 , dc = 32767.50
[PWM] setPWM_manual: _dutycycle = 32767 , frequency = 2000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 500 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 156 , _actualFrequency = 2003
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 78 , actual DC% = 50.32
=================================================================================================
Actual data: pin = 1, PWM DutyCycle % = 50.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=================================================================================================
[PWM] setPWM_DCPercentage_manual: DCPercentage = 55.00 , dc = 36044.25
[PWM] setPWM_manual: _dutycycle = 36044 , frequency = 2000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 500 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 156 , _actualFrequency = 2003
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 86 , actual DC% = 55.41
=================================================================================================
Actual data: pin = 1, PWM DutyCycle % = 55.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=================================================================================================
[PWM] setPWM_DCPercentage_manual: DCPercentage = 60.00 , dc = 39321.00
[PWM] setPWM_manual: _dutycycle = 39321 , frequency = 2000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 500 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 156 , _actualFrequency = 2003
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 94 , actual DC% = 60.51
=================================================================================================
Actual data: pin = 1, PWM DutyCycle % = 60.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=================================================================================================
[PWM] setPWM_DCPercentage_manual: DCPercentage = 65.00 , dc = 42597.75
[PWM] setPWM_manual: _dutycycle = 42597 , frequency = 2000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 500 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 156 , _actualFrequency = 2003
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 101 , actual DC% = 64.97
=================================================================================================
Actual data: pin = 1, PWM DutyCycle % = 65.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=================================================================================================
[PWM] setPWM_DCPercentage_manual: DCPercentage = 70.00 , dc = 45874.50
[PWM] setPWM_manual: _dutycycle = 45874 , frequency = 2000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 500 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 156 , _actualFrequency = 2003
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 109 , actual DC% = 70.06
=================================================================================================
Actual data: pin = 1, PWM DutyCycle % = 70.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=================================================================================================
[PWM] setPWM_DCPercentage_manual: DCPercentage = 75.00 , dc = 49151.25
[PWM] setPWM_manual: _dutycycle = 49151 , frequency = 2000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 500 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 156 , _actualFrequency = 2003
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 117 , actual DC% = 75.16
=================================================================================================
Actual data: pin = 1, PWM DutyCycle % = 75.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=================================================================================================
[PWM] setPWM_DCPercentage_manual: DCPercentage = 80.00 , dc = 52428.00
[PWM] setPWM_manual: _dutycycle = 52428 , frequency = 2000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 500 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 156 , _actualFrequency = 2003
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 125 , actual DC% = 80.25
=================================================================================================
Actual data: pin = 1, PWM DutyCycle % = 80.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=================================================================================================
[PWM] setPWM_DCPercentage_manual: DCPercentage = 85.00 , dc = 55704.75
[PWM] setPWM_manual: _dutycycle = 55704 , frequency = 2000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 500 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 156 , _actualFrequency = 2003
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 133 , actual DC% = 85.35
=================================================================================================
Actual data: pin = 1, PWM DutyCycle % = 85.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=================================================================================================
[PWM] setPWM_DCPercentage_manual: DCPercentage = 90.00 , dc = 58981.50
[PWM] setPWM_manual: _dutycycle = 58981 , frequency = 2000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 500 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 156 , _actualFrequency = 2003
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 141 , actual DC% = 90.45
=================================================================================================
Actual data: pin = 1, PWM DutyCycle % = 90.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=================================================================================================
[PWM] setPWM_DCPercentage_manual: DCPercentage = 95.00 , dc = 62258.25
[PWM] setPWM_manual: _dutycycle = 62258 , frequency = 2000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 500 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 156 , _actualFrequency = 2003
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 149 , actual DC% = 95.54
=================================================================================================
Actual data: pin = 1, PWM DutyCycle % = 95.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=================================================================================================
[PWM] setPWM_DCPercentage_manual: DCPercentage = 100.00 , dc = 65535.00
[PWM] setPWM_manual: _dutycycle = 65535 , frequency = 2000.00
[PWM] setPeriod_TimerA0: F_CPU = 20000000 , microseconds = 500 , TCA_Freq_mult = 1.00
[PWM] setPeriod_TimerA0: pwmPeriod = 156 , _actualFrequency = 2003
[PWM] setPWM_Int: TCA0 pin = 1 dutycycle = 157 , actual DC% = 100.64
=================================================================================================
Actual data: pin = 1, PWM DutyCycle % = 100.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=================================================================================================
The following is the sample terminal output when running example PWM_SpeedTest on AVR_ATtiny3217, to demonstrate how to use new faster setPWM_DCPercentageInt_manual()
function in wafeform creation, The time is 94197ns
compared to 169577ns
when using setPWM_DCPercentage_manual()
function of v1.1.0
. The setPWM_manual
with 97465ns
is to be used with pre-calculated values in array
Starting PWM_SpeedTest on AVR_ATtiny3217
ATtiny_PWM v1.2.0
=================================================================================================
Actual data: pin = 1, PWM DutyCycle % = 0.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=================================================================================================
Average time of setPWM function USING_DC_PERCENT
count=10607, ns=94277
count=10616, ns=94197
count=10616, ns=94197
count=10607, ns=94277
count=10616, ns=94197
count=10615, ns=94206
count=10607, ns=94277
count=10616, ns=94197
count=10616, ns=94197
count=10616, ns=94197
count=10607, ns=94277
Starting PWM_SpeedTest on AVR_ATtiny3217
ATtiny_PWM v1.2.0
=================================================================================================
Actual data: pin = 1, PWM DutyCycle % = 0.00, PWMPeriod = 500.00, PWM Freq (Hz) = 2000.0000
=================================================================================================
Average time of setPWM function not USING_DC_PERCENT
count=10248, ns=97580
count=10261, ns=97456
count=10260, ns=97465
count=10252, ns=97541
count=10260, ns=97465
count=10260, ns=97465
count=10252, ns=97541
count=10260, ns=97465
count=10261, ns=97456
count=10260, ns=97465
count=10252, ns=97541
count=10260, ns=97465
Debug is enabled by default on Serial.
You can also change the debugging level _PWM_LOGLEVEL_
from 0 to 4
// Don't define _PWM_LOGLEVEL_ > 0. Only for special ISR debugging only. Can hang the system.
#define _PWM_LOGLEVEL_ 0
If you get compilation errors, more often than not, you may need to install a newer version of the core for Arduino boards.
Sometimes, the library will only work if you update the board core to the latest version because I am using newly added functions.
Submit issues to: ATtiny_PWM issues
- Search for bug and improvement.
- Support to TCD0 to change frequency
- Basic
TCA0
hardware PWM-channels for Arduino AVR ATtiny-based boards (ATtiny3217, etc.) using megaTinyCore - Add example PWM_StepperControl to demo how to control Stepper Motor using PWM
- Add example PWM_manual to demo how to correctly use PWM to generate waveform
- Add function
setPWM_DCPercentage_manual()
to facilitate the setting PWM DC manually by usingDCPercentage
, instead ofabsolute DCValue
depending on varying PWMPeriod - Catch low frequency error and use lowest permissible frequency
- Optimize speed with new
setPWM_DCPercentageInt_manual
function to improve speed almost 50% compared tosetPWM_DCPercentage_manual
of previousv1.1.0
- Add example PWM_SpeedTest to demo the better speed of new
setPWM_DCPercentageInt_manual
function
Many thanks for everyone for bug reporting, new feature suggesting, testing and contributing to the development of this library.
- Thanks to Paul van Dinther for proposing new way to use PWM to drive Stepper-Motor in Using PWM to step a stepper driver #16, leading to v1.0.1
Paul van Dinther |
If you want to contribute to this project:
- Report bugs and errors
- Ask for enhancements
- Create issues and pull requests
- Tell other people about this library
- The library is licensed under MIT
Copyright (c) 2022- Khoi Hoang