Added PCA9685_ACTUAL_CLOCK_FREQUENCY macro

README.md

@@ -237,7 +237,8 @@ Every other extension e.g. *cinclude* would do, but *hpp* seems to be common sen
 
 # Using the new *.hpp files
 In order to support [compile options](#compile-options--macros-for-this-library) more easily,
-the line `#include <ServoEasing.h>` must be changed to  `#include <ServoEasing.hpp>` in your main program (aka *.ino file with setup() and loop()).
+the line `#include <ServoEasing.h>` must be changed to  `#include <ServoEasing.hpp>`
+in your main program (aka *.ino file with setup() and loop()).
 
 In **all other files** you must use `#include <ServoEasing.h>`, to **prevent `multiple definitions` linker errors**:
 
@@ -259,6 +260,7 @@ Modify them by enabling / disabling them, or change the values if applicable.
 | Name | Default value | Description |
 |-|-|-|
 | `USE_PCA9685_SERVO_EXPANDER` | disabled | Enables the use of the PCA9685 I2C expander chip/board. |
+| `PCA9685_ACTUAL_CLOCK_FREQUENCY` | 25000000L | Change it, if your PCA9685 has another than the default 25 MHz internal clock. See chapter 2 and 5 of the PCA9685 Datasheet "25 MHz typical internal oscillator requires no external components". |
 | `USE_SOFT_I2C_MASTER` | disabled | Saves up to 1756 bytes program memory and 218 bytes RAM for PCA9685 I2C communication compared with Arduino Wire. |
 | `USE_SERVO_LIB` | disabled | Use of PCA9685 normally disables use of regular servo library. You can force additional using of regular servo library by defining `USE_SERVO_LIB`. See [below](https://github.com/ArminJo/ServoEasing#using-pca9685-16-channel-servo-expander). |
 | `PROVIDE_ONLY_LINEAR_MOVEMENT` | disabled | Disables all but LINEAR movement. Saves up to 1540 bytes program memory. |
@@ -394,7 +396,8 @@ This will print internal information visible in the Arduino *Serial Monitor* whi
 # Revision History
 ### Version 3.1.1
 - Added function `getCurrentMicroseconds()`.
-- Improved many examples.
+- Improved many and added workaround for ESP32 bug in while loops in examples.
+- Added `PCA9685_ACTUAL_CLOCK_FREQUENCY` macro.
 
 ### Version 3.1.0
 - SAMD51 support by Lutz Aumüller.

examples/PCA9685_Expander/PCA9685_Expander.ino

@@ -29,6 +29,7 @@
 
 // Must specify this before the include of "ServoEasing.hpp"
 #define USE_PCA9685_SERVO_EXPANDER    // Activating this enables the use of the PCA9685 I2C expander chip/board.
+//#define PCA9685_ACTUAL_CLOCK_FREQUENCY 26000000L // Change it, if your PCA9685 has another than the default 25 MHz internal clock.
 //#define USE_SOFT_I2C_MASTER           // Saves 1756 bytes program memory and 218 bytes RAM compared with Arduino Wire
 //#define USE_SERVO_LIB                 // If USE_PCA9685_SERVO_EXPANDER is defined, Activating this enables force additional using of regular servo library.
 //#define USE_LEIGHTWEIGHT_SERVO_LIB    // Makes the servo pulse generating immune to other libraries blocking interrupts for a longer time like SoftwareSerial, Adafruit_NeoPixel and DmxSimple.

examples/PCA9685_ExpanderAndServo/PCA9685_ExpanderAndServo.ino

@@ -39,6 +39,7 @@
 
 // Must specify this before the include of "ServoEasing.hpp"
 #define USE_PCA9685_SERVO_EXPANDER    // Activating this enables the use of the PCA9685 I2C expander chip/board.
+//#define PCA9685_ACTUAL_CLOCK_FREQUENCY 26000000L // Change it, if your PCA9685 has another than the default 25 MHz internal clock.
 //#define USE_SOFT_I2C_MASTER           // Saves 1756 bytes program memory and 218 bytes RAM compared with Arduino Wire
 #define USE_SERVO_LIB                 // If USE_PCA9685_SERVO_EXPANDER is defined, Activating this enables force additional using of regular servo library.
 //#define PROVIDE_ONLY_LINEAR_MOVEMENT  // Activating this disables all but LINEAR movement. Saves up to 1540 bytes program memory.

examples/PCA9685_ExpanderFor32Servos/PCA9685_ExpanderFor32Servos.ino

@@ -38,6 +38,7 @@
 
 // Must specify this before the include of "ServoEasing.hpp"
 #define USE_PCA9685_SERVO_EXPANDER    // Activating this enables the use of the PCA9685 I2C expander chip/board.
+//#define PCA9685_ACTUAL_CLOCK_FREQUENCY 26000000L // Change it, if your PCA9685 has another than the default 25 MHz internal clock.
 //#define USE_SOFT_I2C_MASTER           // Saves 1756 bytes program memory and 218 bytes RAM compared with Arduino Wire
 //#define USE_SERVO_LIB                 // If USE_PCA9685_SERVO_EXPANDER is defined, Activating this enables force additional using of regular servo library.
 //#define PROVIDE_ONLY_LINEAR_MOVEMENT  // Activating this disables all but LINEAR movement. Saves up to 1540 bytes program memory.

src/ServoEasing.h

@@ -390,8 +390,12 @@ extern const char *const easeTypeStrings[] PROGMEM;
 #define PCA9685_MODE_1_SLEEP            4
 #define PCA9685_FIRST_PWM_REGISTER   0x06
 #define PCA9685_PRESCALE_REGISTER    0xFE
+#if !defined(PCA9685_ACTUAL_CLOCK_FREQUENCY)
+// See chapter 2 and 5 of the PCA9685 Datasheet "25 MHz typical internal oscillator requires no external components"
+#define PCA9685_ACTUAL_CLOCK_FREQUENCY   25000000L // 25 MHz this is the default frequency
+#endif
 
-#define PCA9685_PRESCALER_FOR_20_MS ((25000000L /(4096L * 50))-1) // = 121 / 0x79 at 50 Hz
+#define PCA9685_PRESCALER_FOR_20_MS ((PCA9685_ACTUAL_CLOCK_FREQUENCY /(4096L * 50)) - 1) // = 121 / 0x79 at 50 Hz
 
 // to be used as values for parameter bool aStartUpdateByInterrupt
 #define START_UPDATE_BY_INTERRUPT           true