Re: IRQ problem with PCMCIA

From: David Hinds
Date: Sun Aug 21 2005 - 17:18:22 EST


On Sun, Aug 21, 2005 at 08:43:50PM +0200, Hesse, Christian wrote:
> Hello everybody,
>
> seems like I have a problem with PCMCIA/PCCARD. If I transfer data
> to or from a CF card inserted via adapter system waits for
> interrupts most of the time: Cpu(s): 21.2% us, 7.9% sy, 0.0% ni,
> 0.0% id, 1.7% wa, 69.2% hi, 0.0% si This results in a very
> unresponsive system and a transfer rate of up to 1MB/s (my new
> camera writes with up to 10MB/s on the card...).

The drivers are working correctly; the problem is with the CF flash
adapter you're using. There are two kinds of CF-to-PCMCIA adapters.
Some are 16-bit PCMCIA cards, which are in most cases limited to a bus
throughput of ~1 MB/sec, regardless of what the CF card is capable
of. There are also 32-bit CF adapter cards, that are much faster,
limited only by the speed of the CF device. Here are two:

http://www.delkin.com/delkin_products_adapters_cardbus.html
http://www.lexarmedia.com/readers/cf32bit.html

-- Dave
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