Hi all,

CF+ and Compact Flash Specification (rev 4.0) specifies Ultra DMA
as an optional protocol for PC Card:
"Ultra DMA operations can take place in any of the three basic
interface modes: PC Card Memory mode, PC Card I/O mode, and True
IDE (the original mode to support UDMA)." (page 54)

Has anyone tried this? What specific CF memory cards are know to
implement it?

Also the summary of PCI1131 from Texas Instruments says that it
"supports 16-Bit Distributed Direct Memory Access (DMA) on both PC
Card sockets". Signal names seem to match the CF specification.

Any ideas if both can work together?

I'm looking into experimenting with improving CF memory card
performance
using a passive adapter for PowerBook G3 under Linux. Firmware is
capable of booting the machine from CF (this is the reason to stick
with the passive adapter). Currently I get about 1.66MB/s when reading
Kingston CF/512-S on Linux 2.6.20. The driver is reading from the
device
using 16-bit IO, and from my timing of IO access, it seems that data
are transferred at the rate of 1 short word of data every 1us (seems
a bit long when comparing with timing diagrams of PCI1131).


Regards,

Piotr Krysiuk