At 09:59 -0700 10/28/11, Jeffrey Engle wrote: >Ok, I'd like some input hereŠ > >Is the PRAM battery needed? newer macs, older macsŠ. please chime in:-) In my >understanding, this little battery does a whole lot more than just "set my >time and date".. honestly if that was the case, Apple would've got rid of the >thing a long time ago?? my 2 bitsŠ. I'm interested in hearing your >thoughts/facts on the subject.
In 1984 the pram battery was used to maintain power on the flip flops that were used to store not only the clock display settings but a bunch of other user preferences that needed to be present during shut down. By 1993 or so I personally was using other forms of static memory that were capable of storing the likes of preference values without any external power. RAMTRON , a company here in Colorado Springs, was quite proud of its efforts in that field called ferroelectrics. By the late 1990s we had devices that could retain a lot of memory using nothing but stored electric charge on the gates of metal oxide , CMOS, devices. You needed external power to change the charges on the gates but they would remain charged when power was removed. Now we have whole plug in "disks" that fit in USB connectors. Gigabytes of erasable but still non-volatile RAM are simple. Electrically erasable programmable read only memory, EEPROM, is the acronym these days. Entire operating systems can remain ready to go when power is applied. 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. The question is just when, by model number, did Apple join the crowd. My Mac IIFX requires a battery to start up its power supply. It's an interesting feature that makes it possible to shut down on a power failure without worrying about fits and false starts as the power company comes back on line. That just might be the last Mac that did it that way. It was a part of the Apple Desktop Bus that allowed the start up button on the keyboard. -- --> Halloween == Oct 31 == Dec 25 == Christmas <-- -- 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
