Silicon_Knight
Member
Registered: Nov 1999
Location:
Posts: 40 |
Lemme try explain:
In the traditional computer sense, RAM is the memory that gets erased when the machine powers down. It is fast; in fact it's the fastest form of memory available. ROM are "burned" at a factory, much like a CD. I believe access time for ROM is about the same as RAM, though one might be faster.
Using the CD-ROM analogy, FlashROM is like a CD Rewritable. It can be rewritten by a software, or end user. In a hand held enviroment, Flash ROM is used for loading the operating system; something that doesn't need to be done much often. In fact, PalmOS 3.1H which is loaded on all Visors already have most of the patches for Palm 3.3 installed.
FlashROM is expensive, so it's use is minimal. That's why it's not included at all in the Visor. The user's memory is actually RAM. The Palm Device requires the battery to keep it alive, and a capacitor to keep it hot while you change batteries. The power consumption is EXTREMELY low, and a Palm OS device can keep it's memory in the "off" state for over a year, without memory loss. For all pratical purposes, this implementation is not obvious to the consumer (except to make the device cheaper).
So, yes, if you pull the batteries out, and let it sit for half hour, you will be losing data. But if you are most hand held users, you'll be replacing the batteries right away when you're changing batteries, and you hotsync, which backs up the data onto a machine anyway.
Flash cartridges are flash rom cartridges (I believe - someone correct me if I'm wrong). That's why the 8Mb cartridge is so expensive, you'll notice that it's almost $10.00 per Mbs. They act as an extension to the Visor's 8Mb existing, but don't need a battery (or power from the Palm device) to be kept alive (again, someone correct me if I'm wrong).
The difference between the 8Mb Flash and the 8Mb backup is that the 8Mb backup is designed to just make a mirror image of the 8Mbs of memory in the visor. In other words, you load the cartridge in, press a button, and bam, it makes a copy of what's there. There's no real intellgence in the cartridge (and I am not too sure what type of chips it uses). OTOH, the 8Mb Flash is designed to be almost like an external drive to the visor; there's actually a program that runs on insertion that notify the system what files are on the 8Mb cartridge. You can then selectivelly load data or documents off the 8Mb flash cart.
Hope this helps.
-=- SiKnight
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