> Sometime, probably in the very early 90's, the PRAM battery became > unnecessary except to keep a clock running. > > With time servers on the net even that requirement has disappeared for > connected installations and even for portables that can see a cell phone > tower.
With the passage of time, the "leakage" current of the CMOS circuitry was improved to the point that the persistent parameters could be retained for years, even if no battery was present. However, as the RTC function cycles the circuitry one every 1/32,000-ths of a second * , there is some external power required for this function. * The actual crystal is 32,768 Hz, and it can be fine-tuned using an external variable capacitor. -- You received this message because you are a member of G-Group, a group for those using G3, G4, and G5 desktop Macs - with a particular focus on Power Macs. The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to g3-5-list@googlegroups.com For more options, visit this group at http://groups.google.com/group/g3-5-list
