add channelCount (#13)

* add channelCount, documentation, update examples

PCA9685.cpp

@@ -2,7 +2,7 @@
 //    FILE: PCA9685.cpp
 //  AUTHOR: Rob Tillaart
 //    DATE: 24-apr-2016
-// VERSION: 0.3.3
+// VERSION: 0.3.4
 // PURPOSE: Arduino library for I2C PCA9685 16 channel PWM 
 //     URL: https://github.com/RobTillaart/PCA9685_RT
 //
@@ -17,6 +17,7 @@
 //  0.3.1  2021-01-05  Arduino-CI + unit test
 //  0.3.2  2021-01-14  WireN support
 //  0.3.3  2021-12-23  update library.json, license, readme, minor edits
+//  0.3.4  2022-01-03  add channelCount()
 
 
 #include "PCA9685.h"
@@ -145,7 +146,7 @@ uint8_t PCA9685::readMode(uint8_t reg)
 void PCA9685::setPWM(uint8_t channel, uint16_t onTime, uint16_t offTime)
 {
   _error = PCA9685_OK;
-  if (channel > 15)
+  if (channel >= _channelCount)
   {
     _error = PCA9685_ERR_CHANNEL;
     return;
@@ -167,7 +168,7 @@ void PCA9685::setPWM(uint8_t channel, uint16_t offTime)
 void PCA9685::getPWM(uint8_t channel, uint16_t* onTime, uint16_t* offTime)
 {
   _error = PCA9685_OK;
-  if (channel > 15)
+  if (channel >= _channelCount)
   {
     _error = PCA9685_ERR_CHANNEL;
     return;
@@ -193,8 +194,9 @@ void PCA9685::setFrequency(uint16_t freq, int offset)
 {
   _error = PCA9685_OK;
   _freq = freq;
-  if (_freq < 24) _freq = 24;       // page 25 datasheet
-  if (_freq > 1526) _freq = 1526;
+  //  limits frequency see page 25 datasheet
+  if (_freq < PCA9685_MIN_FREQ) _freq = PCA9685_MIN_FREQ;
+  if (_freq > PCA9685_MAX_FREQ) _freq = PCA9685_MAX_FREQ;
   // removed float operation for speed
   // faster but equal accurate
   // uint8_t scaler = round(25e6 / (_freq * 4096)) - 1;
@@ -226,7 +228,7 @@ int PCA9685::getFrequency(bool cache)
 void PCA9685::digitalWrite(uint8_t channel, uint8_t mode)
 {
   _error = PCA9685_OK;
-  if (channel > 15)
+  if (channel >= _channelCount)
   {
     _error = PCA9685_ERR_CHANNEL;
     return;

PCA9685.h

@@ -1,9 +1,9 @@
 #pragma once
 //
-//    FILE: PCA9685.H
+//    FILE: PCA9685.h
 //  AUTHOR: Rob Tillaart
 //    DATE: 24-apr-2016
-// VERSION: 0.3.3
+// VERSION: 0.3.4
 // PURPOSE: Arduino library for I2C PCA9685 16 channel PWM
 //     URL: https://github.com/RobTillaart/PCA9685_RT
 
@@ -12,7 +12,7 @@
 #include "Wire.h"
 
 
-#define PCA9685_LIB_VERSION                 (F("0.3.3"))
+#define PCA9685_LIB_VERSION                 (F("0.3.4"))
 
 // ERROR CODES
 #define PCA9685_OK                          0x00
@@ -21,6 +21,10 @@
 #define PCA9685_ERR_MODE                    0xFD
 #define PCA9685_ERR_I2C                     0xFC
 
+//  get/setFrequency()
+#define PCA9685_MIN_FREQ                    24
+#define PCA9685_MAX_FREQ                    1526
+
 
 class PCA9685
 {
@@ -34,6 +38,8 @@ class PCA9685
   void    reset();
   bool    isConnected();
 
+  uint8_t  channelCount() { return _channelCount; };
+
   // reg = 1, 2  check datasheet for values
   void    writeMode(uint8_t reg, uint8_t value);
   uint8_t readMode(uint8_t reg);
@@ -78,6 +84,7 @@ class PCA9685
   uint8_t _address;
   int     _error;
   int     _freq = 200;  // default PWM frequency - P25 datasheet
+  uint8_t  _channelCount = 16;
 
   TwoWire*  _wire;
 };

README.md

@@ -37,6 +37,7 @@ Lower frequencies do better than higher frequencies.
 Library does not support multiple Wire instances (yet).
 - **void reset()** resets the library to start up conditions.
 - **bool isConnected()** checks if address is available on I2C bus.
+- **uint8_t channelCount()** returns the number of channels = 16.
 
 
 ### Mode

examples/PCA9685_allOFF_test/PCA9685_allOFF_test.ino

@@ -27,7 +27,7 @@ void setup()
   Serial.println();
 
   pinMode(PIN, INPUT_PULLUP);
-  for (int channel = 0; channel < 16; channel++)
+  for (int channel = 0; channel < PCA.channelCount(); channel++)
   {
     PCA.setPWM(channel, 0, 1000);
   }

examples/PCA9685_digitalWrite_test/PCA9685_digitalWrite_test.ino

@@ -9,6 +9,8 @@
 // to see the frequency of the PWM
 
 
+#include "Arduino.h"
+#include "Wire.h"
 #include "PCA9685.h"
 
 

examples/PCA9685_maxPWM_test/PCA9685_maxPWM_test.ino

@@ -9,6 +9,8 @@
 // to see the frequency of the PWM
 
 
+#include "Arduino.h"
+#include "Wire.h"
 #include "PCA9685.h"
 
 

examples/PCA9685_setFrequency_offset/PCA9685_setFrequency_offset.ino

@@ -14,6 +14,8 @@
 // Note: the higher the frequency, the more inaccurate the real frequency,
 
 
+#include "Arduino.h"
+#include "Wire.h"
 #include "PCA9685.h"
 
 

examples/PCA9685_setFrequency_test/PCA9685_setFrequency_test.ino

@@ -9,6 +9,8 @@
 // to see the frequency of the PWM
 
 
+#include "Arduino.h"
+#include "Wire.h"
 #include "PCA9685.h"
 
 
@@ -35,8 +37,8 @@ void setup()
   pinMode(IRQ_PIN, INPUT_PULLUP);
   attachInterrupt(digitalPinToInterrupt(IRQ_PIN), irq, RISING);  // CHANGE
 
-  PCA.setFrequency(24);
-  PCA.setPWM(15, 0, 4095);    // gives 2 changes per interval
+  PCA.setFrequency(PCA9685_MIN_FREQ);   // == 24
+  PCA.setPWM(15, 0, 4095);              // gives 2 changes per interval
 
   Serial.println("\nSET\tGET\tGET%\tIRQ\tIRQ%");
 }
@@ -73,7 +75,7 @@ void loop()
     Serial.print("\n");
 
     freq += 4;
-    if (freq >= 1526) freq = 24;
+    if (freq >= 1526) freq = 24;  //  page 25 datasheet; PCA9685_MAX_FREQ, PCA9685_MIN_FREQ
     PCA.setFrequency(freq);
     PCA.setPWM(15, 0, 4095);
 

examples/PCA9685_test01/PCA9685_test01.ino

@@ -5,6 +5,8 @@
 // PUPROSE: test PCA9685 library
 
 
+#include "Arduino.h"
+#include "Wire.h"
 #include "PCA9685.h"
 
 
@@ -36,7 +38,7 @@ void testSetON()
   Serial.print(millis());
   Serial.print("\t");
   Serial.println("Test - setHIGH");
-  for (uint8_t channel = 0; channel < 16; channel++)
+  for (uint8_t channel = 0; channel < ledArray.channelCount(); channel++)
   {
     ledArray.digitalWrite(channel, HIGH);
   }
@@ -48,7 +50,7 @@ void testSetOFF()
   Serial.print(millis());
   Serial.print("\t");
   Serial.println("Test - setLOW");
-  for (uint8_t channel = 0; channel < 16; channel++)
+  for (uint8_t channel = 0; channel < ledArray.channelCount(); channel++)
   {
     ledArray.digitalWrite(channel, LOW);
   }
@@ -60,7 +62,7 @@ void testPWMMode()
   Serial.print(millis());
   Serial.print("\t");
   Serial.println("Test - setPwm getPWM");
-  for (uint16_t channel = 0; channel < 16; channel++)
+  for (uint16_t channel = 0; channel < ledArray.channelCount(); channel++)
   {
     // every next line ~twice as much time
     ledArray.setPWM(channel, channel * 127, channel * 255);

examples/PCA9685_test02/PCA9685_test02.ino

@@ -5,8 +5,11 @@
 // PUPROSE: test PCA9685 library
 
 
+#include "Arduino.h"
+#include "Wire.h"
 #include "PCA9685.h"
 
+
 PCA9685 ledArray(0x40);
 
 
@@ -39,7 +42,7 @@ void testDigitalWrite(uint8_t mode)
   Serial.print(millis());
   Serial.print("\t");
   Serial.println(__FUNCTION__);
-  for (int channel = 0; channel < 16; channel++)
+  for (int channel = 0; channel < ledArray.channelCount(); channel++)
   {
     ledArray.digitalWrite(channel, mode);
     delay(100);
@@ -73,7 +76,7 @@ void testPWMMode()
   Serial.print(millis());
   Serial.print("\t");
   Serial.println(__FUNCTION__);
-  for (uint16_t channel = 1; channel < 16; channel++)
+  for (uint16_t channel = 1; channel < ledArray.channelCount(); channel++)
   {
     // every next line ~twice as much time
     ledArray.setPWM(channel, channel * 127, channel * 255);

keywords.txt

@@ -27,10 +27,13 @@ lastError	KEYWORD2
 
 # Constants (LITERAL1)
 PCA9685_LIB_VERSION	LITERAL1
+
 PCA9685_OK	LITERAL1
 PCA9685_ERROR	LITERAL1
 PCA9685_ERR_CHANNEL	LITERAL1
 PCA9685_ERR_MODE	LITERAL1
 PCA9685_ERR_I2C	LITERAL1
 
+PCA9685_MIN_FREQ	LITERAL1
+PCA9685_MAX_FREQ	LITERAL1
 

library.json

@@ -15,7 +15,7 @@
     "type": "git",
     "url": "https://github.com/RobTillaart/PCA9685_RT.git"
   },
-  "version": "0.3.3",
+  "version": "0.3.4",
   "license": "MIT",
   "frameworks": "arduino",
   "platforms": "*",

library.properties

@@ -1,5 +1,5 @@
 name=PCA9685_RT
-version=0.3.3
+version=0.3.4
 author=Rob Tillaart <rob.tillaart@gmail.com>
 maintainer=Rob Tillaart <rob.tillaart@gmail.com>
 sentence=Arduino library for I2C PCA9685 16 channel PWM 

test/unit_test_001.cpp

@@ -31,6 +31,8 @@
 
 #include <ArduinoUnitTests.h>
 
+#include "Arduino.h"
+#include "Wire.h"
 #include "PCA9685.h"