Misplaced Pages

This is an old revision of this page, as edited by Plugwash (talk | contribs) at 18:55, 9 March 2007 (→5 Volts?). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Heres the problem: Need to connect a 3G PCMCIA card to my expresscard slot. Any solutions?

Anon contribution

An anon over on WP:AFC requested this be created. As his proposed article has information that seems to be missing, I'm reduplicating it here:

"An ExpressCard is a modular I/O expansion card for laptops and similar portable computing and data procesing devices. Essentially, an ExpressCard is the logical successor to PC Cards (often incorrectly called PCMCIA cards) that have been used in laptops for almost two decades. PC Cards come in two flavors, "16-bit" PC Cards, which are the architectural equivalent of an ISA-standard desktop plug-in card, and "32-bit" PC Cards (also known as "Cardbus" cards) which are the architectural equivalent of a PCI-standard desktop card. Extending this sequence, an "ExpressCard" is the logical and architectural equivalent of a PCI Express card for a portable electronic device such as a laptop.

Physically, an ExpressCard slot in a laptop outwardly resembles a PC Card slot, however ExpressCard slots are not backwards compatible to PC Cards. ExpressCards themselves are the same 5mm thickness as a Type II PC Card, but come in two formats neither of which has the same dimensions as a PC Card. The "ExpressCard/54" format is 54x75mm, however, it has rectangular chunk removed from one corner and thus is not rectangular, but rather has 6 edges. The "ExpressCard/34" form factor is 34x75mm, and looks kind of like a stick of gum (or, from a computer perspective, kind of like the original early Sony "Memory Stick"). Both are clearly recognizable as being different from PC Cards."

--maru (talk) contribs 07:11, 24 May 2006 (UTC)

Sizes

Do 54 cards fit in 34 slots? What about 34 in 54? --Abdull 08:39, 27 May 2006 (UTC)

Added this --Profnick 01:11, 3 July 2006 (UTC)

Yes, 34 fit in 54 slots, but not the other way around. The 54 cards are simply wider, but use the same connector. 69.87.200.181 13:56, 25 November 2006 (UTC)

Compared to PC card

I'd like to see some technical explanation on why these are superior to the PC card. --Yamla 16:12, 29 June 2006 (UTC)

I added some info from the ExpressCard Group web site to address your concern. --Profnick 01:11, 3 July 2006 (UTC)

I've created a new image to show the differences between the two architectures, to replace the old, unlicensed one. The new image has been uploaded under a free license (Creative Commons BY-SA-2.5). --Indrek 01:07, 2 August 2006 (UTC)

If it interfaces through USB, it will be anything but superior to Cardbus. USB is a CPU hog and doesn't deliver bandwidth equal to PCI in any way. I would certainly hope that no company would implement ExpressCard thru USB. --Swaaye 21:08, 7 March 2007 (UTC)

Expresscard offers two seperate interfaces on the host connector. PCI-Express and USB, it is up to card manufacturers to decide what to use. Some devices even use both at the same time (the belkin docking station linked in this article uses the PCI-e part for video and the usb part for everything else). Plugwash 21:45, 7 March 2007 (UTC)

Ahhh, I see what you mean. The port itself offers both PCI Express and USB interfaces. I was interpreting it as the slot would interface through either USB or PCIe, like a Cardbus PCI bridge but to USB instead (ick!), depending on the implementation. --Swaaye 01:11, 8 March 2007 (UTC)

Afaict cardbus is pretty much a variant of PCI with some additions for hotplugging and detection of old 16 bit pcmcia cards. Cardbus cards have PCI IDs allocated and often use the same controller chips as thier desktop PCI counterparts (e.g. i have a cardbus nic with an RTL8139 in it). Plugwash 02:05, 8 March 2007 (UTC)

Yeah Cardbus is basically 32-bit 33 MHz PCI. It was a huge upgrade from 16-bit PCMCIA. If the cardbus controller is decent, it can perform as well as PCI. However, many notebooks aren't shipping with decent cardbus controllers. I myself had to deal with that in an Emachines notebook a couple of years ago. Creative's Audigy 2 Notebook is very sensitive to such issues and it barely worked in that machine. Works fine in this Dell though, with a better cardbus controller. There have also been tests done by companies building ethernet NICs into cardbus and they have seen performance issues with some cardbus controllers. Hopefully Expresscard will eliminate these penny pinching issues. --Swaaye 18:24, 9 March 2007 (UTC)

5 Volts?

The voltage claims don't make sense. These cards are said to run on lower voltages. But the USB 2.0 standard requires 5 volts. Is it available on this connector, or not? 69.87.200.181 14:00, 25 November 2006 (UTC)

I believe this is a reference to the PCI Express option of the interface. The USB side would of course have to have the voltage required by the USB specification, as you said, 5v. --Pcloches 22:14, 1 December 2006 (UTC)

Full and low speed USB at least use 3.3V signaling (they use 5V power though). Not sure about high speed. Plugwash 18:55, 9 March 2007 (UTC)

available?

It would be good to have some good external links to lists of what cards are actually available in this format, at least until it becomes more common. 69.87.200.181 14:00, 25 November 2006 (UTC)

Perhaps the Where to Buy section of the ExpressCard site fits the bill? Someone want to write up a small section for available cards or should this just go in the references? --Pcloches 22:11, 1 December 2006 (UTC)

Attached Diagram

The attached diagram

shows that the CardBus card connected through a CardBus controller, while the USB option of the ExpressCard connects directly to the system bus, which is a bit misleading.

Is there even really a CardBus controller? Isn't it just an extension of the PCI bus (or ISA bus on the older PCMCIA cards)?

--Pcloches 22:11, 1 December 2006 (UTC)

From the article itself: "whereas CardBus utilizes an interface controller that only interfaces with PCI". --Indrek 21:17, 23 December 2006 (UTC)

Well the usb part certainly doesn't go direct to the system bus and PCIe is a tree structure not a bus, i don't know if the PCIe part of expresscard differs from standard PCIe at all though (obviously it needs to support hotplugging though). Plugwash 03:02, 18 January 2007 (UTC)

The Rabbit

A picture of ExpressCard's rabbit logo should be on this page. Jigen III 11:30, 7 December 2006 (UTC)