DS1307 Support and demo program v2 with ZBasic structures

[stevech]

ZBasic now has (beta test) support for structures.

The attached code uses simple structures for date/time in conjunction with the DS1307 clock chip (I2C bus).

Three bas files
1. Test and demo - set time via PC batch file
2. DS1307 I/O
3. Leap year and other date/time utilties

[mikep]

You are getting good at this stuff

I would suggest moving the structure from the test program to the interface module because it is part of the interface.

[stevech]

or put the structure in a file by itself and #include it whenever needed - like you do in C

[mikep]

Well that is possibly true because it is such a common and useful structure. But in other cases I like to use the encapsulation provided by the modules - think C++ rather than C