The "heart" of nnCron is a crontab file where all the data required to run a task are stored: time, events, commands and conditions on which commands are executed. Crontab file is an ordinary plain-text file. It can be created and/or edited in any available text editor.
Immediately after nnCron is installed, a crontab file named nncron.tab will be created in nnCron's home directory; it will be used as the default crontab. There are no limitations on number of crontabs that can be used simultaneously, so it may be a good idea to create several different crontabs to keep different types of tasks in different files; for example, I find it convenient to use crontab file nncron.tab for routine tasks, backup.tab for tasks that have to do with creating backup copies of files, hotkey.tab for tasks that are started with shortcut keys, and test.tab for various experiments and testing.
To view the list of active crontabs, open Options dialog box by doubleclicking nnCron icon in system tray. Use buttons Edit, Add, and Delete to add new crontabs or deactivate those you no longer use.
Starting times and frequency of actions are recorded in crontab files in so-called cron format, inherited from Unix systems.
Each minute, nnCron checks time of last modification of crontab files; if it notices that files were changed, it automatically "rereads" them. If you have manually changed some data in a crontab file and you don't want to wait while nnCron reloads it automatically, you can hasten reloading of crontab by typing in command line
or by selecting 'Reload crontabs' in menu which appears when you click right mouse button on nnCron icon in system tray.
If you used GUI to add or edit a task , crontab will be reloaded immediately, without waiting for the next minute. You can tune up nnCron crontabs-reloading behaviour using nncron.ini variable ReloadImmediately.
There are two versions of syntax used for recording data in crontab files: classic mode and extended mode. Note, please, that crontab line length should not exceed 512 characters.