Aahhh so close, yet so far away..

From the searches I have done, it seems that there are only a few Compact Flash card readers that will work in Linux, the most popular of which is the SanDisk SDDR-31. Since that one was not available at the local Fry's, I thought I'd waste a weekend and try a couple of others. The one I am trying now is a Digitex CSU-LA1. I was encouraged by the fact that it came with linux instructions.

Well, after two recompiles and an sg-3-utils install, I am unable to find any files on the CF card. Everything I think I need is compiled in or loaded as a module:

USB support
USB mass storage
preliminary USB filesystem
uhci, usb-uhci (I can load one at a time)
/dev virtual filesystem
SCSI support
SCSI disk support (sd_mod.o)
/proc filesystem support

I have not messed with the Memory Technology Devices (MTD) stuff, as everyone seems to do fine without it.

I can make the flash reader's LED go on and off by issuing modprobe uhci, rmmod uhci.

I issue this command, per the instructions:
mount -t usbdevfs none /proc/bus/usb
which seems to go without a hitch, "none" is mounted ok! There is now a /proc/bus/usb/001 and 002 directory, and the devices and drivers files. The 001 and 002 directories contain small files 001 and 002, little 18-byte binaries, but none of the files I know are on the card.

The device, according to sg_map, is /dev/sg0. I know this because my only other "scsi" device is my cd burner, listed as /dev/sr0. sg0 is actually a link to /dev/scsi/host0/bus0/target0/lun0/generic. I have never had devices such as /sda or /sda1 come up.

I put an entry in /etc/fstab:
/dev/sg0 /camera auto noauto,user 0 0
and of coarse made a /camera directory to mount to.
It makes no difference if I put /dev/sg0 in fstab or the whole /dev/scsi/host0... path

Typing mount /camera always leads to the error message "sg0 is not a block device" This occurs whether or not I have uhci loaded, or "none" mounted, or the thing plugged in! What a pissoff!

My questions to you guys:
Am I missing something obvious? Do I have access to the card yet and just don't realize it? Where are the files?
Should I waste more time with this reader, buy a SanDisk reader, or just don't use a CF reader at all? I suppose I can install gphoto to get my damn pictures, but that's not nearly as cool as using the flash card as a miniature drive.

Thanks,
John

What really matters is whether you get a SCSI device scan read in "dmesg" that mentions /dev/sda. This is after:

modprobe usb-storage

Also, if you are using a stock 8.1 install, that's a year old 2.4.18 kernel. A lot of USB mass storage devices were added in 2.4.19, and a few more in 20. If you are leary of a kernel compile, a slack package of 2.4.19 is available on your favorite Slackware mirror under: Slackware-8.1/patches/packages.

Cheers,

Finegan

Thanks for your reply, finegan.
I upgraded to 2.4.20 and compiled in those options and/or modules.
searching dmesg | less returns no patterns resembling /dev/sda or /dev/sg0, though sg0 does show up in the /dev virtual filesystem. Does it matter that I have no /dev/sda?

lsmod shows the following:
usb-storage is loaded but (unused)
usbcore [uhci usb-storage]
sd_mod also (unused)

loaded but unused... the device is probably listed as claimed by no active driver... yeah, I guess it isn't supported. Might want to check the 2.4.21-preX changelog to see if its mentioned, but I doubt.

Cheers,

Finegan

Thanks finegan, I think I'll keep my trusty 2.4.20 kernel, load up gphoto (and the USB libraries it requires) then just plug in the camera directly.

finegan,
Well after a some dissatisfaction with giving up on the flash drive, and some dependency hell with gphoto2, (I need pkg-config and GTK+- what now!?) I decided to try yet another flash card reader, the abundant SanDisk SDDR-75, and hello, third time's a charm! Here are some good instructions for getting this particular reader to read. You are right that there should be a /dev/sda, and you mount the "partition" /dev/sda1. Anyway, just thought I'd share my experience and recommend SanDisk readers in general.