Does Palm OS support multiple external memory card ?

[UI018397]

Lots of people on the forum is asking for a CF driver, presumably, they want to use CF memory cards as an alternative to the more expensive memory sticks.

This got me thinking.....
Let's say we've got such CF driver that will talk to a CF memory card. But nothing stops a user from plugging in both a CF memory and a MS.

1) What would happen then?
2) Does Palm OS actually support multiple external memory cards?
3) Which takes precedence?
4) Do we have sufficient knowledge of how the MS architecture is mapped to the Palm VFS (in order to disable it if needs be)?

Perhaps a Palm developer can comment on this.

[n2ifp]

Pocket PC's could differentiate between memory cards. Someday we'll find out if the Clie can, although everyone seems to think it possible if Sony would only supply the information.

If it can address the WiFi card, it should be able to address a CF memory card, with the right driver of course.

[xlr8]

Being a sony launcher the memory stick pic down the bottom only would load a memory stick but when u go to delete something theres a drop down menu suggesting u could click on more than one memory card

[UI018397]

But I don't mean identifying the CF card, but
whether Palm OS itself supports multiple memory card !

[UI018397]

Originally posted by xlr8
Being a sony launcher the memory stick pic down the bottom only would load a memory stick but when u go to delete something theres a drop down menu suggesting u could click on more than one memory card

Do you mean the drop down box that currently let us choose between the memory card and the handheld RAM ?

[yorrick]

From what I've seen, it would be a tentative 'yes'
Why?
1) Filez and card managers create a drop down list of possible memory locations - RAM and card.
2) You can create a virtual memory card with Palm RAM Disk (from www.handwatch.com) which would create in memory a virtual memory card and you can see this in Filez etc.

The only problem is getting extra memory slot and the hardware to work with two memory cards.

[UI018397]

Originally posted by yorrick
From what I've seen, it would be a tentative 'yes'
Why?
1) Filez and card managers create a drop down list of possible memory locations - RAM and card.
2) You can create a virtual memory card with Palm RAM Disk (from www.handwatch.com) which would create in memory a virtual memory card and you can see this in Filez etc.

The only problem is getting extra memory slot and the hardware to work with two memory cards.

I will have a look at Palm RAM Disk.
Thanks !

[n2ifp]

Originally posted by UI018397
But I don't mean identifying the CF card, but
whether Palm OS itself supports multiple memory card !

I am sure you would have to manualy select it or have an application written to access the correct memory storage. I would say one or the other, but not both at the same time. In others words they wouldn't be additive.

[applejosh]

The Handera handles two memory cards just fine. So in practice it's possible; I just don't know how much, if any, "tweaking" needs to be done to the Palm OS internals.

[Eric S]

The HandEra was the first, but there is also AlphaSmart's Dana. I don't think that this will be a problem, as long as the apps don't assume that there will only be one VFS expansion slot.

[Token User]

Rather than speculation, I thought I would dg into it a little deeper. From the PalmOS 5.0 Developer documentation, there is a whole library dedicated to VFS (Virtual File System) Manager functions - including mounting the media, and enumerating the slots that are present.

So, the OS has the support, HOWEVER, the services that a licensee chooses to implement are not determined by PalmSource.

From the PalmOS Programmers API Ref (pg 2269) ...
"Because not every system has (or needs) Virtual File System (VFS) Manager services, applications wishing to use these services should check to make sure they are present before calling them."

I get the impression that it is an all or nothing deal though - you either HAVE VFS, or don't have VFS, but can't pick and choose what you want to implement. Since the Clie range support Memory Sticks, they then have the VFS functionality built in.

What does this mean for the possible use of both MS and CF memory devices? Since most devices only cater for a single memory slot, many apps will not build an enumerated list of available memory devices, instead just polling the initial memory slot.

Once the CF driver issue is addressed ( :rolleyes: ), the authors of things like PowerRun, SilverScreen, ZLauncher, etc., will need to ensure that their code enumerates over the devices to detect memory in slots other than the first one. Not a difficult task, but one that will make the use of the CF slot less useful initially.

[Eric S]

Originally posted by Token User

Once the CF driver issue is addressed ( :rolleyes: ), the authors of things like PowerRun, SilverScreen, ZLauncher, etc., will need to ensure that their code enumerates over the devices to detect memory in slots other than the first one. Not a difficult task, but one that will make the use of the CF slot less useful initially.

I suspect that for many (most?) of those programs that do have issues, just having one or the other plugged in should fix things.

Hmmm... Just realized that I can test this theory. I've got a HandEra 330, a CF card, and an SD card that I don't normally use in the HandEra, I'll spend some time this weekend playing around with it to see what programs handle having one/the other/both cards. Anyone have a favorite program that they want me to test that way?

[cbulock]

Originally posted by Eric S
\ Anyone have a favorite program that they want me to test that way?

Yea, how do the launchers handle multiple cards? Do they look in the /Palm/Launcher folder of both cards? Like, in ZLauncher for example, would it look at backgrounds and themes on both cards?

[ilkera]

I could not get Palm RAM Disk work on my Clie NX70v.
does it work on palmOS 5 ?