Memory Cards

[Blah-Blah]

I am new to the whole PDA area.
Is anyone able to provide a simple explanation of the different memory cards and their relative strengths and weaknesses?
Ie SD, SDIO and MultimediaCard?

[StoneRyno]

I can't really compare the types throughly but as far as I understand SD is superior to Multimedia. And there are some performance differences between brands too. I have a PQI 1GB SD and it benchmarks a lot better than my 256MB Sandisk SD.

[Ion Control]

Secure Digital is the same form factor as the Multimedia Card (MMC) and only introduces the ability to secure the data through various methods. I think the MMC may not have a "read only" switch. Go SD. It's cheaper now than MMC because more people want it. Not sure about SDIO.

The other types are COmpactFlash (quite common for digital cameras and PDAs), Memoery Stick (sony's proprietary technology and only used on Sony devices), SmartMedia (an old, thin card that's on it's way out), and few other niche products (at least, as far as I know).

[applejosh]

SD is slightly thicker than MMC, IIRC, but MMC cards will fit in SD slots. (SD cards won't fit in MMC only slots.) SD has some sort of copyright protection circuitry in it or something like that. MMC cards are (usually) limited to 128MB in size (at least the last time I checked). SD cards can easily be found in 1GB sizes. SD cards (in any size) are generally more readily available than MMC cards. (At least the last time I went to CompUSA and Staples, they didn't have MMC cards but had SD cards out the wazoo.) Supposedly, certain SD cards are a lot faster than MMC, also.

SDIO is a specification for peripherals and doesn't have anything to do with memory. For example, the Wi-fi card from Palm is a SDIO device. I think there are bluetooth devices out there that are SDIO. Maybe some SDIO modems, too, but I don't know for certain.

Cheers.

[athlon64]

Just to put a spin here, but has anyone actually seen a mini-SD card in real life? I saw a picture of one and it is so freaking small.

Chances are that you will be needing a SD memory stick. I suggest a 512 or higher if you listen to MP3's and watch videos. 256 is fine for regular use. Also if you have digital camera, you can take pictures with the same card and view the pictures on the larger screen of a PDA.

[zackepceo]

SD is a card, about 2.5mm thick. It supports capacitied up to 1 or 2 gb now (with more possible in the future). MMC is an older format about 1.8mm thick that can be facory-made to be read-only. They usually are only up to 128MB and are slower than SD. SDIO is a standard that lets you use the SD slot for accessories. A 4-bit SDIO capable slot is going to be faster than a normal 1-bit SD slot. Most PDAs use SD memory, and SD memory is the cheapest to second cheapest.
Compactflash used to be the most common kind of memory, but it's pretty old and big. Roughly 2.3cm by 2.4cm by 6mm. Comes in sizes from about 2 megs to 8 gigabytes, but only a card up to 2 gb will work on Palm OS currently.
Memory Stick and Memory Stick pro is what all the Sony PDAs use. They store from 8 megs to 128MB for the normal memory stick, and 256mb to 2gb for the pro memory sticks. They are chaped like a rectangle and about as thin as an SD card.