PCA9685: Add string based constructor for PWM Controller

src/pca9685/pca9685.cxx

@@ -28,6 +28,7 @@
 #include <string>
 #include <stdexcept>
 
+#include "upm_string_parser.hpp"
 #include "pca9685.hpp"
 
 using namespace upm;
@@ -54,9 +55,9 @@ PCA9685::PCA9685(int bus, uint8_t address, bool raw)
                                   ": mraa_i2c_init() failed");
       return;
     }
-      
+
   mraa_result_t rv;
-  
+
   if ( (rv = mraa_i2c_address(m_i2c, m_addr)) != MRAA_SUCCESS)
     {
       throw std::runtime_error(std::string(__FUNCTION__) +
@@ -71,6 +72,96 @@ PCA9685::PCA9685(int bus, uint8_t address, bool raw)
   enableRestart(true);
 }
 
+PCA9685::PCA9685(std::string initStr) : mraaIo(initStr)
+{
+  mraa_io_descriptor* descs = mraaIo.getMraaDescriptors();
+
+  std::vector<std::string> upmTokens;
+
+  if(mraaIo.getLeftoverStr() != "") {
+    upmTokens = UpmStringParser::parse(mraaIo.getLeftoverStr());
+  }
+
+  if(!descs->i2cs)
+  {
+    throw std::invalid_argument(std::string(__FUNCTION__) +
+                                  ": mraa_i2c_init() failed");
+  }
+  else
+  {
+    if( !(m_i2c = descs->i2cs[0]) )
+    {
+      throw std::invalid_argument(std::string(__FUNCTION__) +
+                                  ": mraa_i2c_init() failed");
+    }
+  }
+
+  // enable auto-increment mode by default
+  enableAutoIncrement(true);
+
+  // enable restart by default.
+  enableRestart(true);
+
+  std::string::size_type sz;
+
+  for (std::string tok : upmTokens) {
+    if(tok.substr(0,10) == "writeByte:") {
+      uint8_t reg = std::stoi(tok.substr(10),&sz,0);
+      tok = tok.substr(10);
+      uint8_t byte = std::stoi(tok.substr(sz+1),nullptr,0);
+      writeByte(reg, byte);
+    }
+    if(tok.substr(0,10) == "writeWord:") {
+      uint8_t reg = std::stoi(tok.substr(10),&sz,0);
+      tok = tok.substr(10);
+      uint16_t word = std::stoi(tok.substr(sz+1),nullptr,0);
+      writeWord(reg, word);
+    }
+    if(tok.substr(0,10) == "modeSleep:") {
+      bool sleep = std::stoi(tok.substr(10),nullptr,0);
+      setModeSleep(sleep);
+    }
+    if(tok.substr(0,14) == "autoIncrement:") {
+      bool ai = std::stoi(tok.substr(14),nullptr,0);
+      enableAutoIncrement(ai);
+    }
+    if(tok.substr(0,10) == "ledFullOn:") {
+      uint8_t led = std::stoi(tok.substr(10),&sz,0);
+      tok = tok.substr(10);
+      bool val = std::stoi(tok.substr(sz+1),nullptr,0);
+      ledFullOn(led, val);
+    }
+    if(tok.substr(0,11) == "ledFullOff:") {
+      uint8_t led = std::stoi(tok.substr(11),&sz,0);
+      tok = tok.substr(11);
+      bool val = std::stoi(tok.substr(sz+1),nullptr,0);
+      ledFullOff(led, val);
+    }
+    if(tok.substr(0,10) == "ledOnTime:") {
+      uint8_t led = std::stoi(tok.substr(10),&sz,0);
+      tok = tok.substr(10);
+      uint16_t time = std::stoi(tok.substr(sz+1),nullptr,0);
+      ledOnTime(led, time);
+    }
+    if(tok.substr(0,11) == "ledOffTime:") {
+      uint8_t led = std::stoi(tok.substr(11),&sz,0);
+      tok = tok.substr(11);
+      uint16_t time = std::stoi(tok.substr(sz+1),nullptr,0);
+      ledOnTime(led, time);
+    }
+    if(tok.substr(0,9) == "prescale:") {
+      uint8_t prescale = std::stoi(tok.substr(9),nullptr,0);
+      setPrescale(prescale);
+    }
+    if(tok.substr(0,15) == "prescaleFromHz:") {
+      float hz = std::stof(tok.substr(15),&sz);
+      tok = tok.substr(15);
+      float oscFreq = std::stof(tok.substr(sz+1),nullptr);
+      setPrescaleFromHz(hz, oscFreq);
+    }
+  }
+}
+
 PCA9685::~PCA9685()
 {
   setModeSleep(true);
@@ -139,7 +230,7 @@ bool PCA9685::setModeSleep(bool sleep)
 
   writeByte(REG_MODE1, mode1);
 
-  // Need a delay of 500us after turning sleep mode off for the oscillator 
+  // Need a delay of 500us after turning sleep mode off for the oscillator
   // to stabilize
   if (!sleep)
     usleep(500);

src/pca9685/pca9685.hpp

@@ -26,6 +26,7 @@
 #include <string>
 #include <mraa/i2c.h>
 #include <mraa/gpio.h>
+#include <mraa/initio.hpp>
 
 #define PCA9685_I2C_BUS 0
 #define PCA9685_DEFAULT_I2C_ADDR 0x60
@@ -37,7 +38,7 @@
 #define PCA9685_ALL_LED 0xff
 
 namespace upm {
-  
+
   /**
    * @brief PCA9685 PWM Controller
    * @defgroup pca9685 libupm-pca9685
@@ -150,7 +151,7 @@ namespace upm {
                    REG_PRESCALE      = 0xfe,
                    REG_TESTMODE      = 0xff  // don't use
     } PCA9685_REG_T;
-    
+
     /**
      * MODE1 bits
      */
@@ -163,7 +164,7 @@ namespace upm {
                    MODE1_EXTCLK      = 0x40, // external clock enable
                    MODE1_RESTART     = 0x80  // restart status
     } PCA9685_MODE1_T;
-    
+
     /**
      * MODE2 bits
      */
@@ -176,7 +177,7 @@ namespace upm {
                    MODE2_RESERVE1    = 0x40, // reserved
                    MODE2_RESERVE2    = 0x80  // reserved
     } PCA9685_MODE2_T;
-    
+
     /**
      * PCA9685 constructor
      *
@@ -185,6 +186,13 @@ namespace upm {
      */
     PCA9685(int bus, uint8_t address = PCA9685_DEFAULT_I2C_ADDR, bool raw = false);
 
+    /**
+     * Instantiates a PCA9685 PWM Controller object based on a given string.
+     *
+     * @param initStr string containing specific information for PCA9685 initialization.
+     */
+    PCA9685(std::string initStr);
+
     /**
      * PCA9685 destructor
      */
@@ -230,7 +238,7 @@ namespace upm {
      * Puts the device in or out of the sleep mode. The device is always
      * in the sleep mode upon power-up.
      *
-     * @param sleep True to put the device in the sleep mode, false to put out  
+     * @param sleep True to put the device in the sleep mode, false to put out
      * @return True if successful
      */
     bool setModeSleep(bool sleep);
@@ -255,7 +263,7 @@ namespace upm {
     bool ledFullOff(uint8_t led, bool val);
 
     /**
-     * Sets the 'LED on' time (0-4,095). See the PCA9685 datasheet for details. 
+     * Sets the 'LED on' time (0-4,095). See the PCA9685 datasheet for details.
      *
      * @param led LED number; valid values are 0-15, PCA9685_ALL_LED
      * @param time 12-bit value at which point the LED turns on
@@ -264,7 +272,7 @@ namespace upm {
     bool ledOnTime(uint8_t led, uint16_t time);
 
     /**
-     * Sets the 'LED off' time (0-4,095). See the PCA9685 datasheet for details. 
+     * Sets the 'LED off' time (0-4,095). See the PCA9685 datasheet for details.
      *
      * @param led LED number; valid values are 0-15, PCA9685_ALL_LED
      * @param time 12-bit value at which point the LED turns off
@@ -287,10 +295,10 @@ namespace upm {
      * prescale can only be set when the device is in the sleep mode.
      *
      * @param hz Desired frequency in Hz
-     * @param oscFreq Oscillator frequency; default is 25 MHz 
+     * @param oscFreq Oscillator frequency; default is 25 MHz
      * @return True if successful
      */
-    bool setPrescaleFromHz(float hz, 
+    bool setPrescaleFromHz(float hz,
                            float oscFreq=PCA9685_INTERNAL_OSC);
 
     /**
@@ -312,6 +320,7 @@ namespace upm {
     bool enableAutoIncrement(bool ai);
 
     bool m_restartEnabled;
+    mraa::MraaIo mraaIo;
     mraa_i2c_context m_i2c;
     uint8_t m_addr;
   };