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JChristensen
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Add getEUI64() function, which converts the EUI-48 ID from an MCP79411 to EUI-64.
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‎MCP79412RTC.cpp‎

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@@ -1,16 +1,16 @@
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/*----------------------------------------------------------------------*
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* MCP79412RTC.cpp - Arduino library for the Microchip MCP79412 *
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* Real-Time Clock. This library is intended for use with the Arduino *
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* MCP79412RTC.cpp - Arduino library for the Microchip MCP7941x *
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* Real-Time Clocks. This library is intended for use with the Arduino *
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* Time.h library, http://www.arduino.cc/playground/Code/Time *
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* *
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* This library is a drop-in replacement for the DS1307RTC.h library *
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* by Michael Margolis that is supplied with the Arduino Time library *
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* above. To change from using a DS1307 RTC to an MCP79412 RTC, it is *
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* above. To change from using a DS1307 RTC to an MCP7941x RTC, it is *
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* only necessary to change the #include statement to include this *
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* library instead of DS1307RTC.h. *
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* *
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* In addition, this library implements functions to support the *
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* additional features of the MCP79412. *
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* additional features of the MCP7941x. *
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* *
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* Jack Christensen 29Jul2012 *
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* *
@@ -337,6 +337,7 @@ void MCP79412RTC::calibWrite(int value)
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/*----------------------------------------------------------------------*
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* Read the unique ID. *
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* For the MCP79411 (EUI-48), the first two bytes will contain 0xFF. *
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* Caller must provide an 8-byte array to contain the results. *
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*----------------------------------------------------------------------*/
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void MCP79412RTC::idRead(byte *uniqueID)
@@ -348,6 +349,28 @@ void MCP79412RTC::idRead(byte *uniqueID)
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for (byte i=0; i<UNIQUE_ID_SIZE; i++) uniqueID[i] = i2cRead();
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}
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/*----------------------------------------------------------------------*
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* Returns an EUI-64 ID. For an MCP79411, the EUI-48 ID is converted to *
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* EUI-64. For an MCP79412, calling this function is equivalent to *
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* calling idRead(). For an MCP79412, if the RTC type is known, calling *
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* idRead() will be a bit more efficient. *
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* Caller must provide an 8-byte array to contain the results. *
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*----------------------------------------------------------------------*/
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void MCP79412RTC::getEUI64(byte *uniqueID)
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{
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byte rtcID[8];
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idRead(rtcID);
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if (rtcID[0] == 0xFF && rtcID[1] == 0xFF) {
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rtcID[0] = rtcID[2];
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rtcID[1] = rtcID[3];
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rtcID[2] = rtcID[4];
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rtcID[3] = 0xFF;
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rtcID[4] = 0xFE;
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}
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for (byte i=0; i<UNIQUE_ID_SIZE; i++) uniqueID[i] = rtcID[i];
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}
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/*----------------------------------------------------------------------*
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* Check to see if a power failure has occurred. If so, returns TRUE *
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* as the function value, and returns the power down and power up *

‎MCP79412RTC.h‎

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Original file line numberDiff line numberDiff line change
@@ -1,16 +1,16 @@
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/*----------------------------------------------------------------------*
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* MCP79412RTC.h - Arduino library for the Microchip MCP79412 *
3-
* Real-Time Clock. This library is intended for use with the Arduino *
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* MCP79412RTC.h - Arduino library for the Microchip MCP7941x *
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* Real-Time Clocks. This library is intended for use with the Arduino *
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* Time.h library, http://www.arduino.cc/playground/Code/Time *
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* *
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* This library is a drop-in replacement for the DS1307RTC.h library *
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* by Michael Margolis that is supplied with the Arduino Time library *
8-
* above. To change from using a DS1307 RTC to an MCP79412 RTC, it is *
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* above. To change from using a DS1307 RTC to an MCP7941x RTC, it is *
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* only necessary to change the #include statement to include this *
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* library instead of DS1307RTC.h. *
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* *
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* In addition, this library implements functions to support the *
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* additional features of the MCP79412. *
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* additional features of the MCP7941x. *
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* *
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* Jack Christensen 29Jul2012 *
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* *
@@ -130,6 +130,7 @@ class MCP79412RTC
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int calibRead(void);
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void calibWrite(int value);
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void idRead(byte *uniqueID);
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void getEUI64(byte *uniqueID);
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boolean powerFail(time_t *powerDown, time_t *powerUp);
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void squareWave(uint8_t freq);
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void setAlarm(uint8_t alarmNumber, time_t alarmTime);

‎ReadMe.md‎

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@@ -6,17 +6,17 @@ Jack Christensen Sep 2012
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![CC BY-SA](http://mirrors.creativecommons.org/presskit/buttons/80x15/png/by-sa.png)
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## Introduction ##
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**MCP79412RTC** is an Arduino library that supports the Microchip MCP79412 Real-Time Clock/Calendar. It is intended to be used with the [Arduino Time library] (http://www.arduino.cc/playground/Code/Time).
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**MCP79412RTC** is an Arduino library that supports the Microchip MCP7941x Real-Time Clock/Calendar chips. It is intended to be used with the [Arduino Time library] (http://www.arduino.cc/playground/Code/Time).
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The **MCP79412RTC** library is a drop-in replacement for the **DS1307RTC** library by Michael Margolis that is supplied with the [Arduino Time library](http://www.arduino.cc/playground/Code/Time). To change from using a DS1307 RTC to an MCP79412 RTC, it is only necessary to use `#include <MCP79412RTC.h>` instead of `#include <DS1307RTC.h>`.
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The **MCP79412RTC** library is a drop-in replacement for the **DS1307RTC** library by Michael Margolis that is supplied with the [Arduino Time library](http://www.arduino.cc/playground/Code/Time). To change from using a DS1307 RTC to an MCP7941x RTC, it is only necessary to use `#include <MCP79412RTC.h>` instead of `#include <DS1307RTC.h>`.
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The **MCP79412RTC** library also implements methods to support the additional features of the MCP79412 RTC.
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The **MCP79412RTC** library also implements methods to support the additional features of the MCP7941x RTC.
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**For more information on the MCP79412, see:**
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[My Blog Post](http://goo.gl/MkBnjR), summarizing the features and advantages of the MCP79412
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[My Power Outage Logger Project](http://goo.gl/RfM5os), an Arduino-based project featuring the MCP79412
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The [Microchip MCP79412 Product Page](http://goo.gl/SHfKe0) for specs, datasheet, etc.
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MCP79412 breakout boards are available at [my Tindie Store](http://goo.gl/UzAVcZ)
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MCP79411 and MCP79412 breakout boards are available at [my Tindie Store](http://goo.gl/UzAVcZ)
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## Installation ##
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To use the **MCP79412RTC** library:
@@ -463,3 +463,19 @@ No function value returned. The RTC's ID is returned to the **uniqueID** array.
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byte buf[8];
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RTC.idRead(buf);
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```
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--------------------------------------------------------------------------------
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###getEUI64(byte *uniqueID)
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#####Description
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Returns an EUI-64 ID. For an MCP79412, calling this function is equivalent to calling `idRead()`. For an MCP79411, the EUI-48 ID is converted to EUI-64. Caller must provide an 8-byte array to contain the results.
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#####Syntax
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`RTC.getEUI64(byte *uniqueID);`
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#####Parameters
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**uniqueID:** An 8-byte array to receive the EUI-64 unique ID _(*byte)_
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#####Returns
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No function value returned. The EUI-64 ID is returned to the **uniqueID** array.
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#####Example
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```c++
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byte buf[8];
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RTC.getEUI64(buf);
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```

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