Pseudo code, kinda awkward though:
PHP Code:
#define START_TIME 20.0
#define END_TIME 7.5
void YourFunction()
{
char strHours[3]; strMinutes[3];
FormatTime(strHours, sizeof(strHours), "%H");
FormatTime(strMinutes, sizeof(strMinutes), "%M");
float hours = StringToFloat(str_hours)
float minutes = StringToFloat(str_minutes);
hours += (minutes/60)
if (hours > START_TIME && hours < END_TIME)
{
//do stuff
}
}