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This example: I2CRTC - name of application: main.c
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Demonstration of talking to a Real Time Clock device on the I2C bus.


Hardware requirements
=====================
Phytec RDK 591 with Philips 591


Software requirements
=====================
Phytec Flash Tools (part of RDK 591)
  www.phytec.com
Raisonance 8051 compiler system - EVAL version sufficient
  www.raisonance.com
or Keil 8051 Compiler System - EVAL version sufficient
  www.keil.com
Optional: Development Assistant-C by RistanCASE
  www.ristancase.ch


Tested using
============

Raisonance 51 Toolset version 6.1.1
Keil C51 Toolset version 6.00


Application description
=============================================
Raisonance specific files have their names prefixed with 'r'.
Keil specific files have their names prefixed with 'k'.
The same source files are used for both compilers.

This program initializes the Real Time Clock to a specific date and time
and then repeatedly reads back the current date and time.
The program results are output through the UART. Connect using:
9600 baud, 8-N-1, no flow control.

This program does not demonstrate the most efficient way of reading and
writing sequential registers, however it does demonstrate the I2C
procedure in the most simple way.
rtc_write_byte and rtc_read_byte do not return until there is either
an error or a successful storage. Both functions wait up to 22ms for the
RTC to be ready using a polling method. The status may be read in the
variable i2c_status.

This program may be easily modified to do the following:
1. trigger an interrupt once a second, once a minute, etc.
2. Allow the user to enter the current date and time via the UART
3. Display the weekday
4. Sample the potentiometer and timestamp the sample
5. Set alarms