On Tue, Nov 24, 2009 at 11:48:56PM +0000, Steve Fosdick wrote:
On Tue, 2009-11-24 at 21:56 +0000, Chris G wrote:
I have a new memory card reader which 'does all the right things' when you plug it in but nothing appears on my desktop. An older, very similar, device works OK and the memory card appears as a drive on my desktop.
How does one diagnose this sort of problem? When I plug in the reader (and card) that doesn't work I see the following in syslog:-
Nov 24 21:49:16 chris kernel: [34956.231212] hub 2-1:1.0: USB hub found Nov 24 21:49:16 chris kernel: [34956.231361] hub 2-1:1.0: 3 ports detected Nov 24 21:49:17 chris kernel: [34956.508106] usb 2-1.1: new high speed USB device using ehci_hcd and address 8 Nov 24 21:49:17 chris kernel: [34956.600669] usb 2-1.1: configuration #1 chosen from 1 choice Nov 24 21:49:17 chris kernel: [34956.600753] hub 2-1.1:1.0: USB hub found Nov 24 21:49:17 chris kernel: [34956.600887] hub 2-1.1:1.0: 3 ports detected Nov 24 21:49:17 chris kernel: [34956.881611] usb 2-1.1.1: new high speed USB device using ehci_hcd and address 9 Nov 24 21:49:17 chris kernel: [34957.031679] usb 2-1.1.1: configuration #1 chosen from 1 choice Nov 24 21:49:17 chris kernel: [34957.031947] scsi7 : SCSI emulation for USB Mass Storage devices Nov 24 21:49:17 chris kernel: [34957.032114] usb-storage: device found at 9 Nov 24 21:49:17 chris kernel: [34957.032116] usb-storage: waiting for device to settle before scanning Nov 24 21:49:22 chris kernel: [34962.033925] usb-storage: device scan complete Nov 24 21:49:22 chris kernel: [34962.043387] scsi 7:0:0:0: Direct-Access Generic Ultra HS-SD/MMC 1.82 PQ: 0 ANSI: 0 Nov 24 21:49:22 chris kernel: [34962.058283] sd 7:0:0:0: [sdc] Attached SCSI removable disk Nov 24 21:49:22 chris kernel: [34962.058361] sd 7:0:0:0: Attached scsi generic sg3 type 0
Chris,
That output looks fine as far as it goes but doesn't show the kernel recognising the partition table and figuring what partitions are available.
If I insert a memory card into my netbook which has a built-in card reader I get:
Nov 24 23:40:44 valouise kernel: [ 77.046367] sd 6:0:0:0: [sdb] 2012160 512-byte logical blocks: (1.03 GB/982 MiB) Nov 24 23:40:44 valouise kernel: [ 77.047220] sd 6:0:0:0: [sdb] Assuming drive cache: write through Nov 24 23:40:44 valouise kernel: [ 77.049610] sd 6:0:0:0: [sdb] Assuming drive cache: write through Nov 24 23:40:44 valouise kernel: [ 77.049631] sdb: sdb1
The last line indicates finding a single partition. Is there a partition table on the media or has the file system been build on the whole media with no partition table (as was done with floppies)? The kernel will work fine with that and you could mount the /dev/sdc device but I suspect whatever automounts the media may not do so in that case.
Yes, you're right, it's not detecting the actual media in the card reader and thus isn't automounting it. I compared the syslog output with the one that works and it's then obvious what isn't happening.
Trouble is I still don't quite know how to diagnose it. I suppose one thing I can try is to plug it into another computer (either a different Linux or an XP one) and see if it works there. It *could* be that the card reader isn't 'seeing' the SD card I'm plugging into it.