Add functionality to address different I2C peripherals.

Author: JChristensen

README.md

@@ -13,7 +13,18 @@ This program is distributed in the hope that it will be useful, but WITHOUT ANY
 
 You should have received a copy of the GNU General Public License along with this program. If not, see <https://www.gnu.org/licenses/gpl.html>
 
-## Important note: Library v2.0.0
+## Version 3.0.0 notes
+Version 3.0.0 adds the ability to address different I2C peripherals for microcontrollers that have more than one (e.g. `Wire`, `Wire1`, etc.) There is one situation that is not backwards compatible with earlier versions of the library. Code that calls `setSyncProvider()` in the [Time library](https://github.com/PaulStoffregen/Time), e.g.:
+```c++
+    setSyncProvider(myRTC.get);
+```
+Needs to change as follows:
+```c++
+    setSyncProvider([](){return myRTC.get();});
+```
+This uses a lambda to provide the Time library with a static function, which it requires. The `MCP79412::get()` function was static in previous versions of the library, but no longer is in v3.0.0. This allows the flexibility to operate with different I2C peripherals.
+
+## Version 2.0.0 notes
 The 2.0.0 version of the library has some significant changes and is not completely backwards compatible with earlier versions. These changes provide a more consistent API and reduce the possibility of name collisions. While sketches using this library will likely require changes as a result, these should be mostly straightforward.
 
  - The library no longer defines an `MCP79412RTC` object, therefore each sketch needs to define  one. (Previous versions of the library defined an `MCP79412RTC` object named `RTC`, although only for AVR architecture. Consider using a name other than `RTC` as this can cause a name collision on some architectures.)
@@ -35,6 +46,7 @@ The following example sketches are included with the **MCP79412RTC** library:
 - **rtcSet1:** Set the RTC date and time using a hard-coded value in the sketch.
 - **rtcSet2:** Similar to **rtcSet1**, a different way to hard-code the date and time.
 - **rtcSet3:** Set the RTC to the sketch compile date and time.
+- **rtc_wire1:** Raspberry Pi Pico example using `Wire1`.
 - **SetSerial:** Set the RTC's date, time, and calibration register from the Arduino serial monitor.
 - **TimeRTC:** Similar to the example of the same name provided with the **Time** library.
 - **PowerOutageLogger:** A comprehensive example that implements a power failure logger using the MCP79412's ability to capture power down and power up times.  Power failure events are logged to the MCP79412's SRAM.  Output is to the Arduino serial monitor.
@@ -71,18 +83,21 @@ Symbolic names used with the squareWave() function (described below).
 - SQWAVE_NONE
 
 ## Constructor
-### MCP79412RTC()
+### MCP79412RTC(TwoWire& wire)
 ##### Description
 Instantiates an `MCP79412RTC` object.
 ##### Syntax
-`MCP79412RTC myRTC;`
+`MCP79412RTC myRTC(wire);`
 ##### Parameters
-None.
+**wire:** An optional parameter to specify which I2C bus to use. If omitted, defaults to `Wire`. *(TwoWire&)*
 ##### Returns
 None.
 ##### Example
 ```c++
-MCP79412RTC myRTC;
+MCP79412RTC myRTC;          // to use Wire
+// or
+MCP79412RTC myRTC(Wire1);   // to use Wire1
+
 ```
 
 ## Initialization function

examples/PowerOutageLogger/PowerOutageLogger.ino

@@ -28,7 +28,7 @@ void setup()
     Serial.begin(115200);
     Serial << F( "\n" __FILE__ " " __DATE__ " " __TIME__ "\n" );
 
-    setSyncProvider(myRTC.get);     // the function to get the time from the RTC
+    setSyncProvider([](){return myRTC.get();}); // the function to get the time from the RTC
     Serial << "RTC SYNC";
     if (timeStatus()!= timeSet) Serial << " FAIL";
     Serial << endl;

examples/SetSerial/SetSerial.ino

@@ -43,7 +43,7 @@ void setup()
 
     // setSyncProvider() causes the Time library to synchronize with the
     // external RTC by calling myRTC.get() every five minutes by default.
-    setSyncProvider(myRTC.get);
+    setSyncProvider([](){return myRTC.get();});
     Serial << endl << F("RTC Sync");
     if (timeStatus() != timeSet) Serial << F(" FAIL!");
     Serial << endl;

examples/TimeRTC/TimeRTC.ino

@@ -11,7 +11,7 @@ void setup()
 {
     myRTC.begin();
     Serial.begin(115200);
-    setSyncProvider(myRTC.get); // the function to get the time from the RTC
+    setSyncProvider([](){return myRTC.get();}); // the function to get the time from the RTC
     if (timeStatus() != timeSet)
         Serial.println("Unable to sync with the RTC");
     else

examples/rtcSet1/rtcSet1.ino

@@ -26,7 +26,7 @@ void setup()
     myRTC.set(now());                   // set the RTC from the system time
 
     // sync the system time with the RTC every five minutes (by default)
-    setSyncProvider(myRTC.get);
+    setSyncProvider([](){return myRTC.get();});
     if (timeStatus() != timeSet)
         Serial.println("Unable to sync with the RTC");
     else

examples/rtc_wire1/rtc_wire1.ino

@@ -0,0 +1,32 @@
+// Arduino MCP79412RTC Library
+// https://github.com/JChristensen/MCP79412RTC
+// rtc_wire1.ino
+// Example sketch with the RTC on the Wire1 bus.
+// Tested with Raspberry Pi Pico using the Arduino-Pico core,
+// https://github.com/earlephilhower/arduino-pico
+
+#include <MCP79412RTC.h>    // http://github.com/JChristensen/MCP79412RTC
+
+constexpr int sdaPin {26}, sclPin {27}; // I2C pins for Wire1 (your pins may vary)
+MCP79412RTC myRTC(Wire1);
+
+void setup()
+{
+    Serial.begin(115200);
+    while (!Serial && millis() < 2000) delay(50);
+
+    Wire1.setSDA(sdaPin); Wire1.setSCL(sclPin);
+    myRTC.begin();
+    setSyncProvider([](){return myRTC.get();}); // the function to get the time from the RTC
+    if (timeStatus() != timeSet)
+        Serial.println("Unable to sync with the RTC");
+    else
+        Serial.println("RTC has set the system time");
+}
+
+void loop()
+{
+    Serial.printf("%.4d-%.2d-%.2d %.2d:%.2d:%.2d\n", year(), month(), day(),
+        hour(), minute(), second());
+    delay(1000);
+}

examples/tiny79412_KnockBang/tiny79412_KnockBang.ino

@@ -35,7 +35,7 @@ void setup()
 
     // setSyncProvider() causes the Time library to synchronize with the
     // external RTC by calling RTC.get() every five minutes by default.
-    setSyncProvider(myRTC.get);
+    setSyncProvider([](){return myRTC.get();});
     Debug.print(F("RTC Sync"));
     if (timeStatus() != timeSet) Debug.print(F(" FAIL!"));
     Debug.println();

library.properties

@@ -1,5 +1,5 @@
 name=MCP79412RTC
-version=2.0.0
+version=3.0.0
 author=Jack Christensen <[email protected]>
 maintainer=Jack Christensen <[email protected]>
 sentence=Arduino library for the Microchip MCP79411/12 Real-Time Clock/Calendar.

src/MCP79412RTC.h

@@ -173,7 +173,7 @@ class MCP79412RTC
         void dumpEEPROM(const uint32_t startAddr=0, const uint32_t nBytes=128);
 
     private:
-        TwoWire& wire;      // reference to Wire or Wire1
+        TwoWire& wire;      // reference to Wire, Wire1, etc.
         void ramWrite(const uint8_t addr, const uint8_t value);
         void ramWrite(const uint8_t addr, const uint8_t* values, const uint8_t nBytes);
         uint8_t ramRead(uint8_t addr);