[SOLVED] Format info for USB flash -- USB-ZIP or USB-HD

[secdroid]

I would like to learn more about the difference between USB-ZIP and USB-HDD, as mentioned in thread http://forum.tinycorelinux.net/index.php/topic,11824.msg62921.html#msg62921

Specifically, some Linux utilities like Gparted claim to create & format FAT32 bootable partitions.  My Acer Aspire One netbook recognizes these partitions as bootable USB-HDD and boots them.  My Dell 530 desktop recognizes them as USB-ZIP and will not boot them.  However, if I format the USB as FAT32 with Windows Vista's Computer Management\Device Management and then use Linux to copy over the boot files, the Dell boots fine.  (Dell does not offer a choice between USB-ZIP and USB-HDD booting; it just shows what it "sees" and gives "boot error" for ZIP.)

Can anyone point me to USB formatting background info?  My google-fu has come up dry.

Alternatively, are there Linux mkfs options (or other Linux commands) that I could try?

[roberts]

USB-HDD is obvious the entire pendrive is used and seen as a hard disk drive.

USB-ZIP usually only for older computers that had BIOS that supported booting from an actual ZIp drive.

For USB-ZIP we trick the BIOS by changing the pendrive's geometry, i.e, chaning the number of heads and sectors being reported from the pendrive to match that of a Zip drive.i.e, what the BIOS would be expecting.

[secdroid]

Thank you, Robert.  I saw what you meant when I used busybox's fdisk -l on a couple of USB flash drives that were identified as WIN95 FAT32, but had vastly different geometries. 

Browsing tc-install.sh shows me how you do it.  Now I have the tools I need to reliably initialize USB flash without Windows.

I suspect that the Dell BIOS is somewhat primitive, despite being up-to-date.  This is the same BIOS that won't boot TC with working networking on a 4 GB RAM system without the additional max_addr=4000M parm, which is apparently not required by TC on most systems with RAM => 4 GB.

[secdroid]

Got a bit more information, so I thought I'd post it in case it helps someone else later.

Googled using geometry in my query.  Most helpful --
http://www.knoppix.net/forum/threads/26883-Ability-to-boot-either-Knoppix-Ubuntu-DSL-from-a-USB-thumb/page2 which cites
http://knoppix.net/wiki/Bootable_USB_Key

Turns out that my Dell BIOS 1.0.18 (up-to-date at 2/24/2009) is actually Phoenix-AwardBIOS v6.00PG, per Windows dxdiag.  Award is said to be funky with USB flash booting.