Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Update Readme #26

Open
wants to merge 3 commits into
base: master
Choose a base branch
from
Open

Update Readme #26

Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
baee21b
Update Readme
ivanseidel Oct 4, 2015
3ea47a3
Rename to .md to take advantage of markdown
eugenius1 Jun 2, 2016
91242ae
Merge pull request #1 from eugenius1/patch-3
ivanseidel Jun 2, 2016
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
98 changes: 59 additions & 39 deletions Readme.txt → README.md
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,5 +1,4 @@
Readme file for Arduino Time Library

# What is "Time"?
Time is a library that provides timekeeping functionality for Arduino.

The code is derived from the Playground DateTime library but is updated
Expand All @@ -12,57 +11,73 @@ Example sketches illustrate how similar sketch code can be used with: a Real Tim
internet NTP time service, GPS time data, and Serial time messages from a computer
for time synchronization.

The functions available in the library include:
## Installation

1. [Download](https://github.com/DmitryAnokhin/Time/archive/master.zip) the Latest release from gitHub.
2. Unzip and rename the Folder name to "Time"
3. Paste the modified folder on your Library folder (On your `Libraries` folder inside Sketchbooks or Arduino software).
4. Reopen the Arduino software.

## Library Reference
The functions available in the library includes:

hour(); // the hour now (0-23)
minute(); // the minute now (0-59)
second(); // the second now (0-59)
day(); // the day now (1-31)
weekday(); // day of the week, Sunday is day 0
month(); // the month now (1-12)
year(); // the full four digit year: (2009, 2010 etc)
- `now()` `unsigned long` - Current millisecond since Jan 1 1970

there are also functions to return the hour in 12 hour format
hourFormat12(); // the hour now in 12 hour format
isAM(); // returns true if time now is AM
isPM(); // returns true if time now is PM
- `hour()` `int` - The hour now (0-23)
- `minute()` `int` - The minute now (0-59)
- `second()` `int` - The second now (0-59)
- `day()` `int` - The day now (1-31)
- `weekday()` `int` - The day of the week. Sunday is 0
- `month()` `int` - The month now (1-12)
- `year()` `int` - The full four digit year (2009, 2010, etc)

now(); // returns the current time as seconds since Jan 1 1970
- `hourFormat12()` `int` - The hour in 12 format
- `isAM()` `uint8_t` - Returns if is AM (`true` or `false`)
- `isPM()` `uint8_t` - Returns if is PM (`true` or `false`)

## Using functions with custom time

The time and date functions can take an optional parameter for the time. This prevents
errors if the time rolls over between elements. For example, if a new minute begins
between getting the minute and second, the values will be inconsistent. Using the
following functions eliminates this probglem
time_t t = now(); // store the current time in time variable t
hour(t); // returns the hour for the given time t
minute(t); // returns the minute for the given time t
second(t); // returns the second for the given time t
day(t); // the day for the given time t
weekday(t); // day of the week for the given time t
month(t); // the month for the given time t
year(t); // the year for the given time t


Functions for managing the timer services are:
setTime(t); // set the system time to the give time t
setTime(hr,min,sec,day,mnth,yr); // alternative to above, yr is 2 or 4 digit yr (2010 or 10 sets year to 2010)
adjustTime(adjustment); // adjust system time by adding the adjustment value

timeStatus(); // indicates if time has been set and recently synchronized
// returns one of the following enumerations:
timeNotSet // the time has never been set, the clock started at Jan 1 1970
timeNeedsSync // the time had been set but a sync attempt did not succeed
timeSet // the time is set and is synced
following functions eliminates this problem.
```c++
time_t t = now(); // store the current time in time variable t
hour(t); // returns the hour for the given time t
minute(t); // returns the minute for the given time t
second(t); // returns the second for the given time t
day(t); // the day for the given time t
weekday(t); // day of the week for the given time t
month(t); // the month for the given time t
year(t); // the year for the given time t
```

## Adjusting Time

- `setTime(unsigned long t)` - Set the system time to the give time t
- `setTime(int hr, int min, int sec, int day, int mnth, int yr)` - Alternative to above
- `adjustTime(long adjustment)` - Adjust system time by adding the adjustment value

```
timeStatus(); // indicates if time has been set and recently synchronized
// returns one of the following enumerations:
timeNotSet // the time has never been set, the clock started at Jan 1 1970
timeNeedsSync // the time had been set but a sync attempt did not succeed
timeSet // the time is set and is synced
```

Time and Date values are not valid if the status is timeNotSet. Otherwise values can be used but
the returned time may have drifted if the status is timeNeedsSync.

setSyncProvider(getTimeFunction); // set the external time provider
setSyncInterval(interval); // set the number of seconds between re-sync


## Utility Macros

There are many convenience macros in the time.h file for time constants and conversion of time units.

To use the library, copy the download to the Library directory.
## Examples

The Time directory contains the Time library and some example sketches
illustrating how the library can be used with various time sources:
Expand Down Expand Up @@ -94,9 +109,11 @@ illustrating how the library can be used with various time sources:
This requires the TinyGPS library from Mikal Hart:
http://arduiniana.org/libraries/TinyGPS

Differences between this code and the playground DateTime library
## Differences between this code and the playground DateTime library

although the Time library is based on the DateTime codebase, the API has changed.
Changes in the Time library API:

- time elements are functions returning int (they are variables in DateTime)
- Years start from 1970
- days of the week and months start from 1 (they start from 0 in DateTime)
Expand All @@ -105,7 +122,7 @@ Changes in the Time library API:
- function added to automatically sync time with extrnal source
- localTime and maketime parameters changed, localTime renamed to breakTime

Technical notes:
## Technical notes:

Internal system time is based on the standard Unix time_t.
The value is the number of seconds since Jan 1 1970.
Expand All @@ -124,8 +141,11 @@ All the members of the Arduino tm structure are bytes and the year is offset fro
Convenience macros provide conversion to and from the Arduino format.

Low level functions to convert between system time and individual time elements are provided:
```c++
breakTime( time, &tm); // break time_t into elements stored in tm struct
makeTime( &tm); // return time_t from elements stored in tm struct
```

The DS1307RTC library included in the download provides an example of how a time provider
can use the low level functions to interface with the Time library.