Chapter 8 Reading / Resetting RTC
64DD has an internal real-time clock (RTC, clock IC) with battery backup. The game user can set the RTC to the current time by using the IPL to open the time-setting menu. When power to the N64 is turned off, the RTC operates on power from the internal battery. Thus, once the user sets it to the current time, the RTC will provide the current time (error ± 60 seconds per month at 25 (C) when the next game is played.
Note: With games that start from Game Pak ROM, please be sure to include in the game program a feature for setting the time. This is recommended because when a REAL_TIME_CLOCK_FAILURE error occurs, it may be possible to finish the game by resetting the time. For details, please see "Chapter 10, "Real-Time Clock Failures."
Note: The game user can freely set the RTC time with the IPL. Thus, the RTC time is not necessarily the current time (or even close to the current time).
There are two RTC functions, both asynchronous. Before calling these functions, be sure to start the leo manager. If it has not been started, -1 is returned.