Synchronize with Caller ID1 This function, when enabled, synchronizes the real-time clock with Caller ID (CID) messaging: call processing compares the time of a CID message to the system real-time clock and, if the difference is more than two minutes, resets the real-time clock to match the time (minutes) of the CID message. The system will analyze each such message (or — if it receives more than four calls with CID information within a one-minute period — as is needed). Select ENABLE or DISABLE by pressing a scroll key (either or ). Choosing ENABLE will allow the CID data to update the time and date. Default: Disabled. Esi-Link-related notes (see also “Function 83: Esi-Link programming,” pages M.9–M.10): If “synchronize with Caller ID” is enabled, Esi-Link time synchronization (from location 700) will be disabled. If “synchronize with Caller ID” is disabled, Esi-Link time synchronization will be allowed (minutes only). When Esi-Link is used, all cabinets’ time will be synchronized by cabinet 700, unless “synchronize with Caller ID” is enabled in Function 142. 2: Adjust for Daylight Saving Time This function, when enabled, causes the real-time clock to adjust itself automatically for Daylight Saving Time (DST). Select AUTO or DISABLE for DST by pressing a scroll key (either or DISABLE is best for those areas that don’t observe DST. Default: Disabled. ). Choosing Note: If this function is enabled and it causes an automatic time change, the system won’t update the realtime clock from either Caller ID messages (Function 1421, above) or Esi-Link time synchronization for 25 hours before and 25 hours after the time change is due to be effective (i.e., 2:00 AM Sunday). Function 143: Clock adjustment This function lets the Installer or Administrator have the system automatically compensate for a clock that’s running too fast or too slow. The clock adjustment speeds up or slows down the clock over a 30-day period by the amount selected. If the system clock is running slow, select a positive value. If the clock is running fast, select a negative value.