PCMCIA CardBus PC Cards Information and FAQ

Updated August 26, 2002

Contents
How to Identify CardBus Cards
How to tell if a device has a CardBus slot
Can I use a Legacy (16-bit) Card in a CardBus Slot?
Can I use a CardBus Card in a Legacy (16-bit) Slot?
How do CardBus Cards Differ from Legacy PC Cards?
Synchrotech CardBus Products

How to Identify CardBus Cards

CardBus ground shield When viewing the PC Card right side up, the area above the pin-outs on the card will have a gold grounding shield strip across it. This strip is necessary to prevent signal noise from interfering with CardBus' high speed (33 Mhz) bus. These 32-bit cards can only be used with 32-bit slots, they are sloted to prevent insertion into 16-bit slots so that the card and the slot won't be damaged by differing voltage requirements. 16-bit cards work in either type of slot, but 32-bit cards only work in 32-bit slots!

How to tell if a device has a CardBus slot

device manager The CardBus specification was released in 1996. Typically, any device manufactured before the second half of 1997 will almost certainly not have a CardBus capable slot. The following is useful in identifying if a machine has CardBus slots or call Synchrotech to find out.

Windows Based Laptop PCs

Access the 'Device Manager' by the means appropriate to the version of Windows installed. Typically right clicking on the computer icon 'My Computer', selecting the 'Hardware' tab, and clicking the 'Device Manager' button will present the device manager dialog. Scroll to locate an entry entitled 'PCMCIA socket' or 'PCMCIA adapter.' Expand the entry and read the device string that is displayed (two slot machines have two entries). If the string contains the term 'CardBus Controller' like in this illustration, then it has a CardBus bridge and you can utilize CardBus PC Cards. Otherwise, the slot is a 16-bit legacy slot and cannot use CardBus Cards.

Many manufacturers make CardBus controllers, which would appear in the 'Device Manager.' Here are some PCMCIA adapter listings that are examples of CardBus controllers.

Toshiba ToPIC97 CardBus Controller
Texas Instruments PCI-1420 CardBus Controller
Ricoh RL5C466 CardBus Controller
O2Micro OZ6832/6833 CardBus Controller

Apple Macintosh PowerBooks

Although this information can often be located in the 'Apple System Profiler' application, Apple lists the following machines as being CardBus capable.

PowerBook G3 Series
PowerBook G3 Series (Bronze Keyboard)
PowerBook (FireWire)
PowerBook G4

The following articles are apropos:

Unix and Unix-like Laptop Systems

If you have hardware from a non-X86 vendor like Sun Microsystems, it is best to contact them to see if the device supports CardBus Cards. If you are using X86 style hardware with a BSD or Linux variant, you can often determine if a machine has CardBus slots by examining the contents of a dmesg or sysctl -A call.

Internal and External Card Readers

Only card readers that are 32 bit on a system level bus can handle CardBus. This effectively rules out everything except PCI based readers. Synchrotech sells genuine Elan PCI to PC CardBus readers that can handle both CardBus and legacy PC Cards. Other readers employ combination PCI and ISA to achieve similar functionality. For a full listing of card readers that can handle CardBus cards see: 'Current CardBus Card Readers Available from Synchrotech.' Be aware that there are some card readers that employ CardBus bridge chips, but do not have CardBus capabilities enabled. As far as we are aware, only genuine Elan readers provide both CardBus and legacy PC Card functionality on a single PCI card.

Can I use a Legacy (16-bit) Card in a CardBus Slot?

Yes, CardBus slots are completely backwards compatible with Legacy (16-bit) cards.

Can I use a CardBus Card in a Legacy (16-bit) Slot?

No, they have groves in the slot guides that are supposed to prevent insertion into legacy slots. Do not try to force a CardBus card into a legacy slot or damage will occur to the card, the slot, or both.

How do CardBus Cards Differ from Legacy PC Cards

CardBus Cards are closely modeled on PCI. They feature a multiplexed 32-bit data and address bus running at speeds as high as 33 MHz providing a peak transfer rate of up to 132 MB a second. They also have the capability of behaving as system-bus masters. CardBus provides laptops and other devices with high throughput capabilities and expansion for modern buses. The following table illustrates some of the differences between legacy (16-bit) and CardBus Cards.

CardBus PC Card
Address/Data Path 32 bit 8 or 16 bit
Bus Speed 33 MHz 8 MHz
Related Protocols PCI, Synchronous Burst ISA, Asynchronous
Theoretical Maximum Throughputs By Mode   32 bit Burst Mode 16 bit memory transfer
(100 ns. min. cycle)
16 bit I/O transfer
(225 ns. min. cycle)
Double Word 132 MB/sec.    
Word 66 MB/sec. 20 MB/sec. 7.84 MB/sec.
Byte 33 MB/sec. 10 MB/sec. 3.92 MB/sec.

Synchrotech CardBus Products

Current CardBus Cards Available from Synchrotech

Ratoc CardBus PC Card Ultra Wide SCSI Adapter
Connect Ultra Wide SCSI devices
Ratoc CardBus PC Card Ultra SCSI Adapter
Connect Ultra SCSI devices
Zonet PC CardBus Ethernet 10/100 BaseT
High speed networking
IOFlex PC CardBus to USB 2.0 Adapter Ruggedized
Provides two USB 2.0 ports
Ratoc PC CardBus to USB 2.0 Adapter
Provides two USB 2.0 ports
Belkin PC CardBus to USB Adapter
Provides two USB ports
IOFlex PC CardBus to FireWire IEEE 1394 Ruggedized
Provides two FireWire ports
Ratoc PC CardBus to FireWire PC
Provides two FireWire ports
Ratoc PC CardBus to FireWire PC Ruggedized
Provides two FireWire ports
Ratoc PC CardBus to FireWire Mac
Provides two FireWire ports

Current CardBus Card Readers Available from Synchrotech

PCM-CR-PC2IC2
PCI Bus to PC Card and CardBus Read-Writer 2 Slot Internal Rear P222
PCM-CR-PC1IC2
PCI Bus to PC Card and CardBus Read-Writer 1 Slot Internal Rear P111
PCM-CR-PC2IFR
PCI Bus to PC CardBus Read-Writer 2 Slot Internal Front Rear P416
PCM-CR-PC1ICL
PCI Bus to PC CardBus Read-Writer 1 Slot Internal Rear Low Profile P311
PCM-CR-PC2IC
PCI/ISA to PC CardBus Read-Writer 2 Slot Internal Rear
This Ratoc device can only read 16 bit cards if the ISA bridge is also installed

Valid HTML 4.01 Valid CSS RSS/XML Feed Follow us on Twitter PCMCIA, CardBus, PC Card