Palm Memory Maximum Increased

Trillan writes "PalmSource has announced that it has developed a technology for increasing the maximum RAM on a Palm handheld from 16MB to 128MB. Hopefully new devices will come out soon to take advantage of it." This looks to me like Palm's plan for remaining competitive against handhelds like Sony's that can add more memory in via memory stick. As more and more multimedia apps are written for PalmOS, more storage space only makes sense.

Comments

It's for competitiveness against PocketPC

[fer]

This looks to me like Palm's plan for remaining competitive against handhelds like Sony's that can add more memory in via memory stick.

Palmsource is responsible for the PalmOS which is used by both Sony *and* Palm devices. It has nothing to do with flash memory (which is used by both hardware brands).

With this development, all Palmsource licensees including Sony and Palm can use up to 128MB internal memory to remain competitive with PocketPC devices.

Palm already competing with Memory Stick

[Anonymous Coward]

This looks to me like Palm's plan for remaining competitive against handhelds like Sony's that can add more memory in via memory stick.

If that's their plan, then they're doing quite well, since 7 (out of 9) of Palm's current models and at least one of the older models all have an SD Card slot. Some links for more info:

• The Palm product family -- look at the "Expansion Cards" row.
• And a list of expansion cards that are available from Palm. (You can use generic SD Cards from other manufacturers too, of course.)

However, as you might be aware from having used Flash in other circumstances, regular RAM is waaaaaaaay faster than Flash, so breaking the 16MB RAM barrier is a Good Thing(tm).

On a completely different note, why doesn't Slashdot allow me to use HTML entites, so that I could write ™ and get a REAL trademark symbol? Is it that hard? It seems like actually extra work to filter them out!

Close, but note quite.

[Anonymous Coward]

On the Palm, there are essentially four kinds of storage:

1. There's the system ROM. The system boots from this. It stores the whole operating system. It's actually flash, but then what isn't these days? Except in rare circumstances, the Flash is never updated. The one exception is that you might once or twice during the life of the system do a major OS upgrade by rewriting the whole system ROM. The system ROM is CPU-addressable memory, meaning it can issue load instructions against it. (Or actually on 68k, they're "move" instructions...)
2. The dynamically allocated memory that's available to applications. This resides in RAM, of course. I'm lumping the stack, the heap, global variables, etc. together here. Also directly CPU-addressable, otherwise how would you have variables in your program? :-)
3. The "databases". The Palm doesn't have files, or actually it does, but it doesn't use them for much and they are an afterthought. Instead, everything is in a "database". This is taken so far that even applications are databases. Their records contain code and other resources they need to run (GUI objects, bitmaps, etc.). Also, the user data is all in databases. Your phone list is a database, your datebook is another, etc., etc. These databases are, for the most part, surprisingly stored on the very same RAM chips as the dynamic data that programs use. Interestingly, the Palm has hardware write protection for this data, though, so even though it runs the good old 68000 instruction set, which is too old to support memory protection in the modern sense, you're still protected if a program goes haywire. It can't accidentally write over your phone list. In order to modify a database, you must go through an API call. Also of interest is the fact that, because important data (applications, all your phone numbers, etc.) is stored in this portion of RAM, when you reboot the Palm, the RAM is not erased. Or at least not that part of it. (Unless you do a cold boot.) So, yes, strange as it may seem, all your important data is stored in plain old RAM for months or years on end.
4. Some Palm models also have removeable flash media. These are much more like a traditional filesystem, with files, directory names, etc. In fact, they are a normal filesystem -- they're good old (!?) FAT. Palm doesn't really have great support for these devices, in that everything for years and years has all been designed to work with databases instead, so the idea of real files is a foreign concept, and most apps can't access them. Of course, there is a complete API for accessing filesystems on the flash if you want to build an application that calls it. Also, the OS does allow you to store read-only databases on the Flash, which means you can store applications there. (Remember, applications are stored in databases. In Palm terminology, a PRC is sort of just a special case of a PDB.)

So, to sum things up, yes, programs are run straight from storage memory, but storage memory happens to be RAM, although the operating system goes to a lot of trouble to mentally keep that RAM separate from the "regular" RAM (used in the traditional way), which is important because all that RAM is really coming from the same pool.

Re:Erm...

[Anonymous Coward]

On the Palm, apparently the really early models (like the Palm Professional I've had since 1997) actually used static RAM, but newer ones use dynamic RAM. On models that use AAA batteries, there is a circuit that steps up the voltage and a pretty powerful capacitor too, so that when you take out the batteries, your memory contents will stay around for quite some time. (An hour, last I tried it.) Apparently, because of the step-up circuit, the capacitor can be kept fully charged even when your (2 x AAA) battery voltage is waaaay down. So, the Palm devices make a valiant effort at keeping power going to the RAM.

I think static RAM was a good choice initially, because the Palm's CPU is actually running only a very small amount of the time. Even when the display is on, the device is in a power-saving mode called "doze" mode until you press a button or something. After a few minutes of inactivity, it goes into a different mode called "sleep" mode, in which current draw goes down even more. So, really, the percentage of the time that the processor is running is really quite small.