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ExpressCards, the new PCMCIA?
randallpowell writes "PC Cards will face competition from ExpressCards in 2005 and 2006. Newer notebook PCs will have them to add wireless, HD-TV broadcast viewing, back-up storage, and more. Microsoft, Dell, and Intel are the major backers of this new expansion slot technology. While smaller, they can easily help users expand their notebook's abilities while PC Cards slowly phase out."
Picture here.
I know this is unrealistic, but if you'd read the article you would have found out that this is an extension of PCI Express and PC manufacturers would like to extend this to Desktop PC's.
:wq
The article is kinda skimpy on details for those of us who are visual-type people, so here is a link to an image comparing a PCMCIA card to the two ExpressCard forms.
Enjoy!
--- Standard disclaimer applies.
For photos and more info see PCMCIA's official site for ExpressCard.
This isn't PCMCIA-like at all. This is not a new bus. This is just a new standardization for how to connect to the existing PCI-E/USB busses, and a standard on card size! Think of it like hot-swap PCI for laptops.
Say you make a ExpressCard 56K modem. It will appear to the system as a USB device. All the card is doing is using the four pins of the slot that connect to the USB controller. The manufacturer will probably reuse 99% of the code from the USB version.
Say you make a ExpressCard video adaptor. Well, here it uses the couple dozen pins in the slot that connect more or less directly to the PCI-E bus. The manufacturer will probably reuse 95% of the code from the PCI-E version of the adaptor.
Beyond support for hot swap, the Linux kernel folks will have to make few changes.
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Unfortunately, reports indicate that Express Cards cannot be used to replace video cards, whether due to heat, archtecture limitations or power consumption, I'm not sure.
It certainly would be nice to be able to upgrade laptop video, even if all you could get would be the Mobile and Go series of GPUs. It would easily increase the life of a laptop gaming system by a few years.
"Sometimes you have fun, and sometimes the fun has you"
Going by the lack of Linux support for other such technologies (mini-PCI wifi on laptops)
Huh? What are you talking about? If a driver supports the Cardbus version, it supports the mini-PCI version.
Wait... we have a 10 Mhz 16-bit PC Card Services bus, a faster, 32 bit CardBus, and what's this now?
Let's pull the white paper.
First, it's 1 PCI Express lane (2.5 Gigabit) plus USB 2.0 (480+ Mbit) in about 20 pins. USB already is installed on laptops -- this is just another form factor for it. I'll ignore it and concentrate on PCI Express.
Now what are we using that requires that much bandwidth? All together now: Uncompressed video and Gigabit Ethernet.
I think we'll have alot of high-end laptops in 2005 have this, the ones who need to muck with video on the go.
A side note: Currently mainstream PCI is a 32-bit bus at 33 Mhz (Although we can double the size and the speed, it's allowed in the spec). That's about 132 Megabytes per sec, or 1.056 Gigabit. Five channel, 48Hz 16-bit audio is about 480 Kbyte/s. 1 Gigabit Ethernet would flood a PCI bus -- but current speeds comming out of Cable, DSL, and Fiber To the House are sub-10baseT speeds.
--
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$Stalag99{"URL"}="http://stalag99.net";
That's PCMCIA technology, not even Cardbus. Too slow for what they are targeting. They want a videocard on one of these, and CF is limited to, max, about 12MB/sec. And CF has to tolerate much slower speeds, like on a 33MHz PDA.
PHEM - party like it's 1997-2003!
Besides the confusion you see here, one may note that ExpressCard, besides the name, is not new at all. It was originaly named "NEWCARD" and announced 2 years ago.
FYI, you can find more about its history here, here, and here.
Its called an antenna. You want your WiFi to work, dont you?
One thing you could do is get a better card that has a detatchable antenna (I have a high power SMC card that does this). Then get a connector cable and a small antenna you can stick on the back of your laptop (they have flat antennas). the cable will only stick out a little (like 1/8"), much better!
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Hello,
3Com makes the unimpressively-named 3CRPAG175, a CardBus card with an XJack-style retractable antenna.
I use one in my IBM ThinkPad T23 and it works quite well--no problems with the antenna getting stuck or failing to retract.
Regards,
Aryeh Goretsky
Dexter is a good dog.
The PCMCIA folks, who are behind this ExpressCard thing, want $349 USD for a copy of the standard, and it is only available in electronic form.
I can understand a small printing fee for a dead-tree copy. But sheesh, when will these guys follow the lead of the IEEE on the 802. standards and just open them up?
Anybody want a peanut?
unfortanitly, you kind of need the antenna. Laptops that contain internal cards have an antenna that usually runs around the display just under the plasitics. Apples laptops for example, used to just have what was pretty much just a PCCARD card with antenna jack. It sat just below the standard card slot but staggered away from the edge of the case.
What would have been nice: including contact for the antenna at pin side of the cards, so the antenna could be optional. Or even just a card that sits flush but has a flexible wire antenna of some type.
Either way with all the memory and device interfaces lately I really don't think this is appropriate. Seems like it been physically reduced too far, though a standard interntal USB interfave would be nice.
=1000101
No, the bandwidth (2.5 Gbps in each direction) of the 1x PCI Express Lane in an ExpressCard can't compete with an AGP8X built in solution (2.1 GB/sec). The ExpressCard power limitations would keep it from working as well, but primarily its bandwidth.
However, the beauty of PCI Express (and ExpressCard) is that your entire machine will be using the same buses for all communication (from the Northbridge on...). None of this AGP for the GPU, PCI for the other devices and an adapter chip to provide CardBus/16-Bit PC Card support that adds complexity and cost to every motherboard. Each device will speak PCI Express and/or USB. All you need is a good Northbridge and the appropriate connectors.
Two ExpressCard/32 cards will fit in the space currently used by a PC Card slot. And the fact that the PCIExpress/USB connection simply taps into the existing buses means that your ExpressCard connectors don't have to be co-located. (Right now your CardBus/PC Card slot MUST be as close as possible to the (typically TI) Cardbus Host Adapter.)
Similarly it should be trivial to add an ExpressCard connector to a desktop (as all new desktops have PCIExpress and USB) and your ExpressCard modules can be reused.
Software isn't an issue because PCI Express is simply a Physical Layer change. All existing PCI code will work with PCI Express out of the box.
There's a fly in the ointment though. Along with ExpressCard, there's also PCI Express Mini Card. PCI Express Mini Card (51mm x 30mm) is very similar in physical size to ExpressCard (75mm x 34mm), but though they both have USB and PCIExpress connections, the connectors are completely different. ExpressCard is a mere 26 pins, but PCI Express Mini Card is 52 (and a PCI Express 1x is 36).
ExpressCard and PCI Express Mini Card aren't competitors, though. PCI Express Mini Cards are for internal connections while your ExpressCard is physically encased and protected. As a hardware designer, though, I wish the two standards shared a bit more commonality. If, at least, the PCB sizes could be exactly the same, we would probably see most ExpressCard products come out as PCI Express Mini Cards (and visa versa). I don't know if that will happen as the circuit board would have to be completely redesigned (for space-constrained designs).
Oh, and one more thing...
PCI Express, even in its 32 Lane (8 GB/sec unencoded) form, has too much latency for direct memory access. Hypertransport does not suffer from this same deficiency.